taxonID	type	description	language	source
03EC2823156C3247FF692882FBF0FC3D.taxon	description	Figs. 5 – 7 (worker)	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823156C3247FF692882FBF0FC3D.taxon	diagnosis	Worker diagnosis: Antennae relatively short, with scapes surpassing posterior margin of head by about a third of their length (SI = 113 – 128); medium to dark brown and sometimes bicolored with darker head and gaster; antennae, mandibles, leg joints, and tarsi yellow in contrast to body; meso-and metacoxae usually somewhat lighter than mesosoma; fine cuticular microsculpture resulting in moderate to strong blue iridescence on head and mesosoma; dense cephalic pubescence; posterior emargination of head strongly variable, from lacking emargination entirely to deep and notch-like.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823156C3247FF692882FBF0FC3D.taxon	description	Compare with: N. contraria, N. polita WORKER. Measurements (n = 12): TL: 1.66 – 2.22; EL: 0.11 – 0.14; EW: 0.09 – 0.10; IOD: 0.29 – 0.34; HE: 0.00 – 0.03; HL: 0.52 – 0.61; HW: 0.44 – 0.52; HLA: 0.17 – 0.21; HLP: 0.24 – 0.29; SL: 0.56 – 0.63; PW: 0.32 – 0.38; MW: 0.17 – 0.20; PrW: 0.22 – 0.28; PDH: 0.18 – 0.22; PTW: 0.09 – 0.14; LHT: 0.47 – 0.55; WL: 0.55 – 0.72; GL: 0.48 – 0.95; SMC: 4 – 7; PMC: 2 – 3; MMC: 2 – 3. Indices: BLI: 125 – 143; CI: 84 – 85; EPI: 58 – 79; HTI: 101 – 110; REL: 19 – 23; SI: 113 – 128. Color: medium to dark brown with yellow to yellow-brown antennae, mandibles, and tarsi; meso- and metacoxae often somewhat lighter than mesosoma; sometimes bicolored with mesosoma lighter than head and gaster; overall cuticle with fine microsculpture resulting in moderate to strong blue iridescence on head and mesosoma. Pilosity: dense cephalic pubescence covering all surfaces of head in full-face view; mesosoma pubescence sparse to absent, limited at most to scattered hairs on pronotum and propodeum, and a fringe of hairs concentrated just posterior to the metanotal groove; gaster pubescence sparse to absent; pair of small, erect setae on apex of petiole. Head: longer than broad and quadrate with distinct posterolateral corners and flattened posterior margin, usually with moderate to strong emargination but sometimes with little to no emargination (HE = 0.00 – 0.03); scapes surpass posterior margin of head by about a third of their length (SI = 113 – 128); median ocellus often large and apparent; lateral ocelli small and often absent or not apparent. Mesosoma: promesonotal area flat to evenly convex in profile view, with posterior margin of pronotum continuous or nearly continuous with anterior margin of mesonotum; propodeum low and unevenly rounded, with posterior face about twice as long as dorsal face. QUEEN. Measurements (n = 2): TL: 3.73 – 4.26; EL: 0.27; HL: 0.76 – 0.79; HW: 0.67 – 0.75; SL: 0.77 – 0.83; WL: 1.25 – 1.27; GL: 1.71 – 2.21. Indices: CI: 97 – 99; REL: 34 – 36; SI: 102 – 105. Relatively large (TL = 3.73 – 4.26). Color: medium to dark brown with yellow to yellow-brown antennae, mandibles, and tarsi; meso- and metacoxae at most somewhat lighter than mesosoma. Pilosity: most of body covered in moderate to dense pubescence; lacking pubescence on posterior face of propodeum; 1 - 3 small, erect setae on anepisternum. Head: as broad as long; scapes surpass posterior margin of head by about a third of their length. MALE. Measurements (n = 4): TL: 1.74 – 2.27; EL: 0.19 – 0.22; HL: 0.48 – 0.57; HW: 0.40 – 0.53; SL: 0.59 – 0.64; WL: 0.59 – 0.86; GL: 0.65 – 0.88. Indices: CI: 83 – 97; REL: 35 – 39; SI: 110 – 122. Color: medium to dark brown with yellow to yellow-brown antennae, mandibles, and tarsi; meso- and metacoxae at most somewhat lighter than mesosoma. Pilosity: dense pubescence on head, mesoscutum, and mesoscutellum; pubescence sparse to absent on pronotum, anepisternum, katepisternum, propodeum, and gaster; lacking pubescence on posterior face of propodeum. Head: as broad as long; compound eyes surpass lateral margins of head in full-face view; scapes surpass posterior margin of head by about a third of their length. Mesosoma: In profile view, propodeum gently rounded with dorsal face about twice as long as posterior face. Genitalia: gonopod narrow and evenly triangular, with nearly straight edges and apex coming to a point (Fig. 71); in ventral view, ventromedial edge of basivolsella weakly and evenly curved (Fig. 91 of Kallal & LaPolla 2012); gonossiculus straight and only slightly longer than cuspis.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823156C3247FF692882FBF0FC3D.taxon	materials_examined	Other material examined: MEXICO: Tamaulipas, El Cielo, Gómez Farías, 23.05216 - 99.24252, 7. ix. 2019, cloud forest, bait trap, Sandoval-Becerra et al. # MXFOR / 0062; Tamaulipas, El Cielo, Gómez Farías, 23.05819 - 99.22366, 12. ix. 2019, oak-pine forest, hand, Sandoval-Becerra et al. # MXFOR / 0102; Tamaulipas, El Cielo, Gómez Farías, 23.0561 - 99.2151, 22. x. 2019, Sandoval-Becerra et al. # MXFOR / 1387; Tamaulipas, El Cielo, Gómez Farías, 23.0561 - 99.2151, 22. x. 2019, Sandoval-Becerra et al. # MXFOR / 1417; Tamaulipas, El Cielo, Gómez Farías, 23.0561 - 99.2151, 22. x. 2019, Sandoval-Becerra et al. # MXFOR / 1433; Tamaulipas, El Cielo, Gómez Farías, 23.0561 - 99.2151, 22. x. 2019, Sandoval-Becerra et al. # MXFOR / 1473; Tamaulipas, El Cielo, Gómez Farías, 23.0521 - 99.2425, 7. ix. 2019, Sandoval-Becerra et al. # MXFOR / 1617; Tamaulipas, El Cielo, Gómez Farías, 23.0486 - 99.2455, 8. ix. 2019, Sandoval-Becerra et al. # MXFOR / 1712; Tamaulipas, El Cielo, Gómez Farías, 23.0521 - 99.2425, 7. ix. 2019, Sandoval-Becerra et al. # MXFOR / 1618; Tamaulipas, El Cielo, Gómez Farías, 23.0486 - 99.2455, 8. ix. 2019, Sandoval-Becerra et al. # MXFOR / 1714; Tamaulipas, El Cielo, Gómez Farías, 23.0455 - 99.2635, 9. ix. 2019, Sandoval-Becerra et al. # MXFOR / 1739; Tamaulipas, El Cielo, Gómez Farías, 23.0413 - 99.2671, 10. ix. 2019, Sandoval-Becerra et al. # MXFOR / 1781; Tamaulipas, El Cielo, Gómez Farías, 23.0486 - 99.2671, 30. x. 2019, Sandoval-Becerra et al. # MXFOR / 1805; Tamaulipas, El Cielo, Gómez Farías, 30. x. 2019, Sandoval-Becerra et al. # MXFOR / 1806; Tamaulipas, El Cielo, Gómez Farías, 23.0486 - 99.2644, 30. x. 2019, Sandoval-Becerra et al. # MXFOR / 1810; Tamaulipas, El Cielo, Gómez Farías, 23.0486 - 99.2644, 30. x. 2019, Sandoval-Becerra et al. # MXFOR / 1824; Tamaulipas, El Cielo, Gómez Farías, 23.0462 - 99.2649, 31. x. 2019, Sandoval-Becerra et al. # MXFOR / 1853; Tamaulipas, El Cielo, Gómez Farías, 23.0462 - 99.2649, 31. x. 2019, Sandoval-Becerra et al. # MXFOR / 1856; Tamaulipas, El Cielo, Gómez Farías, 23.04555 - 99.26355, pine forest, bait trap, 9. ix. 2019, Sandoval-Becerra et al. # MXFOR / 0036; Tamaulipas, El Cielo, Gómez Farías, 23.048673 - 99.264491, cloud-pine forest, hand, 30. x. 2019, Sandoval-Becerra et al. # MXFOR / 0939; Tamaulipas, El Cielo, Gómez Farías, 23.05613 - 99.21519, deciduous forest, bait trap, 22. x. 2019, Sandoval-Becerra et al. # MXFOR / 0124; Tamaulipas, El Cielo, Gómez Farías, 23.0581 - 99.2236, 12. ix. 2019, Sandoval-Becerra et al. # MXFOR / 1580; Tamaulipas, El Cielo, Gómez Farías, 23.0561 - 99.2151, 22. x. 2019, Sandoval-Becerra et al. # MXFOR / 1382; Tamaulipas, El Cielo, Gómez Farías, 23.0561 - 99.2151, 22. x. 2019, Sandoval-Becerra et al. # MXFOR / 1465; Tamaulipas, El Cielo, Gómez Farías, 23.0521 - 99.2425, 7. ix. 2019, Sandoval-Becerra et al. # MXFOR / 1635; Tamaulipas, El Cielo, Gómez Farías, 23.0521 - 99.2425, 7. ix. 2019, Sandoval-Becerra et al. # MXFOR / 1674; Tamaulipas, El Cielo, Gómez Farías, 23.0581 - 99.2236, 12. ix. 2019, Sandoval-Becerra et al. # MXFOR / 1564; Tamaulipas, El Cielo, Gómez Farías, 23.0455 - 99.2635, 9. ix. 2019, Sandoval-Becerra et al. # MXFOR / 1737; U. S. A.: Arizona, Cochise Co., Chiricahua Mts., Pinery Canyon, 6.9 km W Onion Saddle, elev. 1890 m, 11. viii. 1989, S. P. Cover # 2092 (SWRS: CASENT 0102818); Arizona, Cochise Co., Huachuca Mts., Upper Ramsey Canyon, 31.4333 - 110.3167, elev. 1910 m, 18. viii. 2002, under stone, Quercus / Pinus / Pseudotsuga forest, P. S. Ward # 14739 (MCZC: MCZ-ENT 00531422).	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823156C3247FF692882FBF0FC3D.taxon	discussion	Notes: Workers of N. austroccidua most closely resemble those of N. contraria and N. polita. However, this species can be most readily distinguished from N. contraria by the color of its meso- and metacoxae, which are at most only slightly lighter brown than the rest of the body in N. austroccidua. In contrast, N. contraria has whitish meso- and metacoxae that strongly contrast with the rest of the body, which is dark brown. Nylanderia austroccidua is most readily differentiated from N. polita by the latter’s smooth and shiny surface, which lacks the cuticular microsculpture and blue iridescence that is readily observable under microscopy in all other species of this complex. This species does not overlap in range with N. contraria or N. polita and is primarily found in high elevation forests ranging across southwestern North America from central Mexico to Utah (Figs. 2 A, 2 B).	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823156E3241FF692C49FC05F86F.taxon	description	Figs. 8 – 10 (worker); Figs. 11 – 12 (queen); Figs. 13 – 16 (male)	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823156E3241FF692C49FC05F86F.taxon	materials_examined	Holotype worker, MEXICO: Chiapas, 2 km SE Custepec, 15.72197 - 92.94163 ± 100 m, elev. 1850 m, 17. v. 2008, ridge oak forest, sifted litter, R. S. Anderson # RSA 2008 - 010 (USNM: USNMENT 01131317). 6 paratype workers, 1 paratype queen, and 4 paratype males with same locality data as holotype (USNM: USNMENT 01130960, USNMENT 01131318, USNMENT 01131319, USNMENT 01131868, USNMENT 01131869, USNMENT 01131870; MNCR: USNMENT 01131320, USNMENT 01131321, USNMENT 01131322, USNMENT 01131962, USNMENT 01132155).	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823156E3241FF692C49FC05F86F.taxon	diagnosis	Worker diagnosis: Antennae relatively short, scapes surpassing posterior margin by less than a quarter of their length; light brown and sometimes bicolored with medium brown head and gaster; meso- and metacoxae about same color as mesosoma; microsculpture and blue iridescence subtle, most visible on head; dense cephalic pubescence.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823156E3241FF692C49FC05F86F.taxon	description	Compare with: N. austroccidua WORKER. Measurements (n = 12): TL: 1.71 – 2.08; EL: 0.10 – 0.11; EW: 0.07 – 0.09; IOD: 0.30 – 0.33; HE: 0.00 – 0.01; HL: 0.53 – 0.58; HW: 0.44 – 0.48; HLA: 0.18 – 0.21; HLP: 0.23 – 0.27; SL: 0.53 – 0.59; PW: 0.32 – 0.35; MW: 0.18 – 0.21; PrW: 0.23 – 0.29; PDH: 0.17 – 0.25; PTW: 0.11 – 0.15; LHT: 0.40 – 0.50; WL: 0.61 – 0.66; GL: 0.57 – 0.91; SMC: 6 – 8; PMC: 2 – 4; MMC: 2 – 3. Indices: BLI: 134 – 146; CI: 81 – 85; EPI: 70 – 84; HTI: 93 – 113; REL: 18 – 20; SI: 114 – 128. Color: Light brown, sometimes bicolored with medium brown head and gaster; meso- and metacoxae about same color as mesosoma; overall cuticle with some microsculpture resulting in subtle blue iridescence on head and mesosoma. Pilosity: dense cephalic pubescence covering all surfaces of head in full-face view; mesosoma pubescence sparse to absent, at most limited to scattered hairs on pronotum; gaster pubescence sparse to absent; pair of small, erect setae on apex of petiole. Head: longer than broad and quadrate with distinct posterolateral corners and flattened posterior margin, usually with no medial emargination; scapes surpass posterior margin of head by less than a quarter of their length; median ocellus small and not always apparent; lateral ocelli absent or not apparent. Mesosoma: posterior margin of pronotum forming obtuse angle with anterior margin of mesonotum in profile view; propodeum low and evenly rounded, with posterior face about same length as dorsal face. QUEEN. Measurements (n = 1): TL: 2.69; EL: 0.18; HL: 0.60; HW: 0.57; SL: 0.61; WL: 0.92; GL: 1.18. Indices: BLI: 154; CI: 96; REL: 29; SI: 106. Relatively small (TL <3) Color: Uniformly yellow-brown to light brown; Pilosity: most of body covered in moderate to dense pubescence; lacking pubescence on posterior face of propodeum; 5 - 6 small, erect setae on anepisternum. Head: As broad as long; scapes surpass posterior margin of head by about a third of their length. MALE. Measurements (n = 2): TL: 1.79 – 1.92; EL: 0.15 – 0.16; HL: 0.47 – 0.48; HW: 0.41 – 0.43; SL: 0.49 – 0.51; WL: 0.63 – 0.66; GL: 0.69 – 0.78. Indices: BLI: 154 – 155; CI: 87 – 90; REL: 32 – 34; SI: 119 – 120. Color: uniformly light to medium brown; meso- and metacoxae concolorous with mesosoma. Pilosity: dense pubescence on head, mesoscutum, and mesoscutellum; pubescence sparse to absent on pronotum, anepisternum, katepisternum, propodeum, and gaster. Head: as broad as long; compound eyes surpass lateral margins of head in full-face view; scapes surpass posterior margin of head by about a third of their length. Mesosoma: In profile view, propodeum gently and evenly rounded, with dorsal face about as long as posterior face. Genitalia: gonopod broad at base, taper strongly to a narrow, digitiform shape, with the apex rounded and slightly turned upward (Fig. 71); in ventral view, ventromedial edge of basivolsella strongly curved (Fig. 15); gonossiculus mostly straight, gradually curved medially toward penial sclerite, and nearly three times as long as cuspis.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823156E3241FF692C49FC05F86F.taxon	materials_examined	Other material examined: MEXICO: Chiapas, 2 km SE Custepec, 15.72188 - 92.93677 ± 100 m, elev. 1900 m, 19. v. 2008, oak-pine forest, sifted litter, R. S. Anderson # RSA 2008 - 016; Chiapas, 2 km SE Custepec, 15.72216 - 92.94298 ± 100 m, elev. 1820 m, 20. v. 2008, oak forest, sifted litter, R. S. Anderson # RSA 2008 - 020; Chiapas, 2 km SE Custepec, 15.7214 - 92.93909 ± 100 m, elev. 1830 m, 20. v. 2008, hardwood forest, sifted litter, R. S. Anderson # RSA 2008 - 023; Chiapas, 3 km SE Custepec, 15.71578 - 92.93847 ± 50 m, elev. 1700 m, 17. v. 2008, 2 ° mesophil forest, sifted litter, LLAMA # Wa-A- 02 - 2 - 07; Chiapas, 2 km SE Custepec, 15.7208 - 92.95097 ± 50 m, elev. 1520 m, 17. v. 2008, mesophil forest, sifted litter, LLAMA # Wa-A- 02 - 1 - 35; Chiapas, 2 km SE Custepec, 15.72085 - 92.95097 ± 50 m, elev. 1520 m, 17. v. 2008, mesophil forest, sifted litter, LLAMA # Wa-A- 02 - 1 - 34; Chiapas, 2 km SE Custepec, 15.72098 - 92.95095 ± 50 m, elev. 1520 m, 17. v. 2008, mesophil forest, sifted litter, LLAMA # Wa-A- 02 - 1 - 31; Chiapas, 2 km SE Custepec, 15.72098 - 92.95054 ± 50 m, elev. 1520 m, 17. v. 2008, mesophil forest, sifted litter, LLAMA # Wa- A- 02 - 1 - 22; Chiapas, 2 km SE Custepec, 15.72096 - 92.9502 ± 50 m, elev. 1520 m, 17. v. 2008, mesophil forest, sifted litter, LLAMA # Wa-A- 02 - 1 - 11; Chiapas, 2 km SE Custepec, 15.721 - 92.95036 ± 50 m, elev. 1520 m, 17. v. 2008, mesophil forest, sifted litter, LLAMA # Wa-A- 02 - 1 - 04; Chiapas, 3 km SE Custepec, 15.71603 - 92.93808 ± 50 m, elev. 1700 m, 17. v. 2008, 2 ° mesophil forest, sifted litter, LLAMA # Wa-A- 02 - 2 - 19; Chiapas, 3 km SE Custepec, 15.71569 - 92.93849 ± 50 m, elev. 1700 m, 17. v. 2008, 2 ° mesophil forest, sifted litter, LLAMA # Wa-A- 02 - 2 - 09; Chiapas, 3 km SE Custepec, 15.71607 - 92.93812 ± 50 m, elev. 1700 m, 17. v. 2008, 2 ° mesophil forest, sifted litter, LLAMA # Wa-A- 02 - 2 - 17; Chiapas, 3 km SE Custepec, 15.71585 - 92.93811 ± 50 m, elev. 1700 m, 17. v. 2008, 2 ° mesophil forest, sifted litter, LLAMA # Wa-A- 02 - 2 - 23; Chiapas, 5 km NNW Coapilla, 17.18326 - 93.15208 ± 50 m, elev. 1915 m, 25. v. 2008, 2 ° mesophil forest, sifted litter, LLAMA # Wa-A- 04 - 2 - 08; Chiapas, 3 km SE Custepec, 15.71485 - 92.93823 ± 50 m, elev. 1700 m, 17. v. 2008, 2 ° mesophil forest, sifted litter, LLAMA # Wa-A- 02 - 2 - 50; Chiapas, 3 km SE Custepec, 15.71494 - 92.93823 ± 50 m, elev. 1700 m, 17. v. 2008, 2 ° mesophil forest, sifted litter, LLAMA # Wa-A- 02 - 2 - 48; Chiapas, 3 km SE Custepec, 15.71554 - 92.93815 ± 50 m, elev. 1700 m, 17. v. 2008, 2 ° mesophil forest, sifted litter, LLAMA # Wa-A- 02 - 2 - 30; Chiapas, 3 km SE Custepec, 15.71576 - 92.93812 ± 50 m, elev. 1700 m, 17. v. 2008, 2 ° mesophil forest, sifted litter, LLAMA # Wa-A- 02 - 2 - 25; Chiapas, 3 km SE Custepec, 15.7158 - 92.93811 ± 50 m, elev. 1700 m, 17. v. 2008, 2 ° mesophil forest, sifted litter, LLAMA # Wa-A- 02 - 2 - 24; Chiapas, 3 km SE Custepec, 15.71528 - 92.938 ± 50 m, elev. 1700 m, 17. v. 2008, 2 ° mesophil forest, sifted litter, LLAMA # Wa-A- 02 - 2 - 37.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823156E3241FF692C49FC05F86F.taxon	etymology	Etymology: The species epithet combines ‘ brevis ’ (L. = short) and ‘ scapus ’ (L. = stalk), referring to the relatively short antennal scapes of this species.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823156E3241FF692C49FC05F86F.taxon	discussion	Notes: Nylanderia breviscapa workers most closely resemble those of N. austroccidua but with a more compact overall appearance, relatively shorter scapes that barely surpass the posterior margin of the head, and meso- and metacoxae that are about the same color as the mesosoma. The known range of this species is limited to high elevation forests in the southern state of Chiapas, Mexico (Fig. 2 B).	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231569325FFF692E3AFB6EFEE9.taxon	description	Figs. 17 – 19 (worker); Figs. 20 – 21 (queen); Figs. 22 – 25 (male)	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231569325FFF692E3AFB6EFEE9.taxon	materials_examined	Holotype worker, MEXICO: Oaxaca, Cafetal Carlota, 18.04802 - 96.69164 ± 30 m, elev. 1028 m, 12. vi. 2016, liquidambar / cloud forest, sifted litter, R. S. Anderson # RSA 2016 - 136 (USNM: USNMENT 01130973). 5 paratype workers, 3 paratype queens, and 2 paratype males with same locality data as holotype (USNM: USNMENT 01131808, USNMENT 01131970, USNMENT 01131971, USNMENT 01131974, USNMENT 01131975, USNMENT 01131977; MNCR: USNMENT 01131972, USNMENT 01131973, USNMENT 01131976, USNMENT 01131978).	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231569325FFF692E3AFB6EFEE9.taxon	diagnosis	Worker diagnosis: Antennae relatively short, with scapes surpassing posterior margin of head by about a third of their length; dark brown, with antennae, mandibles, leg joints, and tarsi yellow in contrast to body; meso-and metacoxae whitish, strongly contrasting with mesosoma; fine cuticular microsculpture resulting in moderate to strong blue iridescence on head and mesosoma; dense cephalic pubescence; posterior margin of head slightly to moderately emarginate.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231569325FFF692E3AFB6EFEE9.taxon	description	Compare with: N. austroccidua, N. polita. WORKER. Measurements (n = 11): TL: 1.67 – 2.19; EL: 0.10 – 0.12; EW: 0.08 – 0.09; IOD: 0.26 – 0.33; HE: 0.01; HL: 0.52 – 0.58; HW: 0.43 – 0.50; HLA: 0.18 – 0.20; HLP: 0.23 – 0.27; SL: 0.55 – 0.62; PW: 0.29 – 0.36; MW: 0.17 – 0.20; PrW: 0.23 – 0.26; PDH: 0.12 – 0.21; PTW: 0.10 – 0.24; LHT: 0.45 – 0.51; WL: 0.58 – 0.68; GL: 0.57 – 0.95; SMC: 5 – 7; PMC: 2 – 3; MMC: 2. Indices: BLI: 130 – 144; CI: 81 – 85; EPI: 69 – 78; HTI: 101 – 109; REL: 18 – 22; SI: 118 – 132. Color: dark brown with yellow to yellow-brown antennae, mandibles, leg joints, and tarsi; meso- and metacoxae whitish, strongly contrasting with rest of body; overall cuticle with fine microsculpture resulting in moderate to strong blue iridescence on head and mesosoma. Pilosity: dense cephalic pubescence covering all surfaces of head in full-face view; mesosoma pubescence sparse to absent, limited at most to scattered hairs on pronotum and propodeum, and a fringe of hairs concentrated just posterior to the metanotal groove; gaster pubescence sparse to absent; pair of small, erect setae on apex of petiole. Head: longer than broad and quadrate with distinct posterolateral corners and flattened posterior margin, usually with slight to moderate emargination; scapes surpass posterior margin of head by about a third of their length; median ocellus often large and apparent; lateral ocelli small and often absent or not apparent. Mesosoma: promesonotal area flat to evenly convex in profile view, with posterior margin of pronotum continuous or nearly continuous with anterior margin of mesonotum; propodeum low and evenly rounded, with posterior face at most slightly longer than dorsal face. QUEEN. Measurements (n = 3): TL: 3.36 – 3.61; EL: 0.18 – 0.19; HL: 0.62 – 0.64; HW: 0.62 – 0.63; SL: 0.62 – 0.64; WL: 1.03 – 1.10; GL: 1.70 – 1.90. Indices: BLI: 164 – 177; CI: 97 – 100; REL: 29 – 30; SI: 100 – 102. Moderately sized. Color: Medium to dark brown, with whitish meso- and metacoxae. Pilosity: most of body covered in moderate to dense pubescence; lacking pubescence on posterior face of propodeum; 1 - 4 small, erect setae on anepisternum. MALE. Measurements (n = 2): TL: 1.90 – 1.95; EL: 0.16; HL: 0.47; HW: 0.41 – 0.43; SL: 0.51 – 0.52; WL: 0.66 – 0.69; GL: 0.77 – 0.79. Indices: BLI: 152 – 167; CI: 88 – 91; REL: 33 – 35; SI: 121 – 123. Color: medium to dark brown with yellow to yellow-brown antennae, mandibles, and tarsi; whitish meso- and metacoxae. Pilosity: dense pubescence on head, mesoscutum, and mesoscutellum; pubescence sparse to absent on pronotum, anepisternum, katepisternum, propodeum, and gaster. Head: as broad as long; compound eyes surpass lateral margins of head in full-face view; scapes surpass posterior margin of head by about a third of their length. Mesosoma: In profile view, propodeum gently and evenly rounded, with dorsal face about as long as posterior face. Genitalia: gonopod narrow and triangular, with apex coming to a point and slightly turned upward (Fig. 71); in ventral view, ventromedial edge of basivolsella strongly angled at base and sloping laterally toward cuspis (Fig. 24); gonossiculus mostly straight and about twice as long as cuspis.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231569325FFF692E3AFB6EFEE9.taxon	materials_examined	Other material examined: MEXICO: Veracruz, 8 km WSW Xalapa, 19.52123 - 96.99372 ± 100 m, elev. 1570 m, 24. vi. 2016, cloud forest, baiting, ADMAC # Ba-F- 05 - 4 - 01 - 11; Oaxaca, Cafetal Carlota, 18.0479 - 96.69193 ± 30 m, elev. 1021 m, 12. vi. 2016, liquidambar / cloud forest, sifted litter, R. S. Anderson # RSA 2016 - 137; Oaxaca, Cafetal Carlota, 18.04756 - 96.69252 ± 30 m, elev. 1011 m, 12. vi. 2016 ,, liquidambar / cloud forest, sifted litter, R. S. Anderson # RSA 2016 - 138; Oaxaca, Cafetal Carlota, 18.04773 - 96.68953 ± 30 m, elev. 1041 m, 14. vi. 2016, liquidambar / cloud forest, sifted litter, R. S. Anderson # RSA 2016 - 145; Oaxaca, Cafetal Carlota, 18.04784 - 96.69198 ± 30 m, elev. 1019 m, 14. vi. 2016, liquidambar / cloud forest, sifted litter, R. S. Anderson # RSA 2016 - 146; Oaxaca, above Cafetal Carlota, 18.05241 - 96.69106 ± 30 m, elev. 1374 m, 14. vi. 2016, mixed hardwood forest, sifted litter, R. S. Anderson # RSA 2016 - 148; Oaxaca, above Cafetal Carlota, 18.05367 - 96.69183 ± 30 m, elev. 1459 m, 14. vi. 2016, mixed hardwood forest, sifted litter, R. S. Anderson # RSA 2016 - 149; Oaxaca, above Cafetal Carlota, 18.05419 - 96.69207 ± 30 m, elev. 1508 m, 14. vi. 2016, mixed hardwood forest, sifted litter, R. S. Anderson # RSA 2016 - 150; Oaxaca, near Cerro 71, 18.11476 - 96.76884 ± 30 m, elev. 1437 m, 15. vi. 2016, mixed hardwood forest, sifted litter, R. S. Anderson # RSA 2016 - 152; Oaxaca, Agua de Hueso, 18.14653 - 96.7934 ± 30 m, elev. 1915 m, 15. vi. 2016, scrubby cloud forest, sifted litter, R. S. Anderson # RSA 2016 - 153; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04847 - 96.69065 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 1 - 18; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04879 - 96.69065 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa- F- 04 - 1 - 25; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04892 - 96.69065 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 1 - 28; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04901 - 96.69065 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 1 - 30; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.0486 - 96.6907 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 1 - 32; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.0486 - 96.69101 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 1 - 38; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.0486 - 96.69106 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 1 - 39; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.0486 - 96.69116 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 1 - 41; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.0486 - 96.69121 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 1 - 42; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.0486 - 96.69132 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa- F- 04 - 1 - 44; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.0486 - 96.69147 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 1 - 47; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04736 - 96.6903 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 01; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04745 - 96.69018 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 04; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04748 - 96.69014 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 05; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04756 - 96.69002 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa- F- 04 - 2 - 08; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04759 - 96.68999 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 09; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04762 - 96.68995 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 10; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04765 - 96.68991 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 11; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04804 - 96.68954 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 24; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04818 - 96.68967 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa- F- 04 - 2 - 28; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04825 - 96.68974 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 30; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04828 - 96.68977 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 31; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04835 - 96.68984 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 33; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04839 - 96.68987 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 34; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04846 - 96.68994 ± 20 m, 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 36; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04846 - 96.69027 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 46; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04835 - 96.69037 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 49; Veracruz, 8 km WSW Xalapa, 19.5213 - 96.99184 ± 20 m, elev. 1520 m, 22. vi. 2016, cloud forest, sifted litter, ADMAC # Wa-F- 05 - 1 - 25; Veracruz, 8 km WSW Xalapa, 19.52107 - 96.99216 ± 20 m, elev. 1530 m, 22. vi. 2016, cloud forest, sifted litter, ADMAC # Wa- F- 05 - 1 - 33; Veracruz, 8 km WSW Xalapa, 19.52092 - 96.99236 ± 20 m, elev. 1530 m, 22. vi. 2016, cloud forest, sifted litter, ADMAC # Wa-F- 05 - 1 - 38; Veracruz, 8 km WSW Xalapa, 19.5219 - 96.99063 ± 20 m, elev. 1500 m, 22. vi. 2016, cloud forest, sifted litter, ADMAC # Wa-F- 05 - 2 - 09; Veracruz, 8 km WSW Xalapa, 19.52245 - 96.99086 ± 20 m, elev. 1500 m, 22. vi. 2016, cloud forest, sifted litter, ADMAC # Wa-F- 05 - 2 - 22; Chiapas, 5 km NE Coapilla, 17.17602 - 93.13293 ± 300 m, elev. 1990 m, 25. v. 2008, mesophil forest, sifted litter, LLAMA # Wm-A- 04 - 1; Oaxaca, 1 km E San Jerónimo Tecoatl, 18.16841 - 96.90282 ± 10 m, elev. 1800 m, 12. vi. 2016, 2 ° alder forest, sifted litter, ADMAC # Wm- F- 04 - 1 - 02; Oaxaca, 1 km SE Huautla, 18.12357 - 96.83419 ± 10 m, elev. 1650 m, 12. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wm-F- 04 - 1 - 03; Oaxaca, 6 km WNW Ayautla, 18.05281 - 96.72518 ± 10 m, elev. 1570 m, 12. vi. 2016, 2 ° mixed hardwood forest, sifted litter, ADMAC # Wm-F- 04 - 1 - 04; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.05175 - 96.69096 ± 20 m, elev. 1320 m, 14. vi. 2016, 2 ° wet forest, sifted litter, ADMAC # Wm-F- 04 - 1 - 06; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.05369 - 96.69192 ± 20 m, elev. 1460 m, 14. vi. 2016, 2 ° wet forest, sifted litter, ADMAC # Wm-F- 04 - 1 - 07; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.05543 - 96.69253 ± 20 m, elev. 1610 m, 14. vi. 2016, montane wet forest, sifted litter, ADMAC # Wm-F- 04 - 1 - 08; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.05602 - 96.69274 ± 20 m, elev. 1660 m, 14. vi. 2016, montane wet forest, sifted litter, ADMAC # Wm-F- 04 - 1 - 09; Oaxaca, 5 km ENE Huautla, 18.14453 - 96.79799 ± 20 m, elev. 1890 m, 15. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wm-F- 04 - 2 - 02; Veracruz, 8 km WSW Xalapa, 19.52265 - 96.9909 ± 125 m, elev. 1500 m, 22. vi. 2016, cloud forest, sifted litter, ADMAC # Wm-F- 05 - 2 - 01; Veracruz, Las Cañadas, 19.18823 - 96.99155 ± 20 m, elev. 1410 m, 1. vii. 2016, montane wet forest, sifted litter, ADMAC # Wm-F- 07 - 1 - 06; Veracruz, Las Cañadas, 19.19018 - 96.99164 ± 20 m, elev. 1400 m, 1. vii. 2016, montane wet forest, sifted litter, ADMAC # Wm-F- 07 - 1 - 08.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231569325FFF692E3AFB6EFEE9.taxon	etymology	Etymology: The species epithet is derived from ‘ contrarius ’ (L. = contrary), referring to the strong color contrast observed in this species between the white meso- and metacoxae and the medium to dark brown of the rest of the body.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231569325FFF692E3AFB6EFEE9.taxon	discussion	Notes: While the overall habitus of N. contraria workers most strongly resembles that of N. austroccidua and N. polita workers, they are most readily distinguished from both of those species by the stark contrast in color between its whitish meso- and metacoxae and dark brown mesosoma. This species is more likely to be confused with N. austroccidua, as these two species have similar cuticular microsculpture that causes a similar amount of blue iridescence, which N. polita lacks entirely. Nylanderia contraria can be found in moderate to high elevation forests in southern Mexico, and its known range is limited to the states of Oaxaca and Veracruz (Fig. 2 B).	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315763258FF692934FCD2F84D.taxon	description	Figs. 26 – 28 (worker); Figs. 29 – 30 (queen); Figs. 31 – 34 (male)	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315763258FF692934FCD2F84D.taxon	diagnosis	Worker diagnosis: Antennae relatively long, with scapes surpassing posterior margin of head by nearly half their length; usually uniformly yellow with black macrosetae strongly contrasting with overall color; microsculpture and blue iridescence subtle, most visible on head; cephalic pubescence sparse to absent; metatibiae relatively long (HTI> 125). Compare with: N. mosaica, N. usul	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315763258FF692934FCD2F84D.taxon	description	WORKER. Measurements (n = 26): TL: 1.68 – 2.33; EL: 0.09 – 0.13; EW: 0.07 – 0.10; IOD: 0.27 – 0.32; HE: 0.00 – 0.01; HL: 0.48 – 0.60; HW: 0.40 – 0.49; HLA: 0.18 – 0.22; HLP: 0.22 – 0.25; SL: 0.53 – 0.69; PW: 0.29 – 0.37; MW: 0.15 – 0.21; PrW: 0.22 – 0.26; PDH: 0.16 – 0.22; PTW: 0.09 – 0.13; LHT: 0.50 – 0.62; WL: 0.58 – 0.74; GL: 0.61 – 1.02; SMC: 6 – 9; PMC: 2 – 3; MMC: 2 – 3. Indices: BLI: 124 – 152; CI: 81 – 90; EPI: 76 – 90; HTI: 121 – 132; REL: 18 – 22; SI: 124 – 147. Color: usually uniformly yellow with thick, black macrosetae strongly contrasting with overall color, but sometimes light to medium brown with somewhat lighter meso- and metacoxae; overall cuticle with light microsculpture resulting in subtle blue iridescence on head and mesosoma. Pilosity: sparse cephalic pubescence; mesosoma and gaster pubescence sparse to absent; pair of small, erect setae on apex of petiole. Head: longer than broad and quadrate with distinct posterolateral corners and flattened posterior margin, usually with slight to moderate emargination; scapes long, surpassing posterior margin by nearly half their length; all three ocelli absent or not apparent. Mesosoma: posterior margin of pronotum forming obtuse angle with anterior margin of mesonotum in profile view; propodeum low and evenly rounded, with posterior face about same length as dorsal face. QUEEN. Measurements (n = 2): TL: 3.13 – 3.28; EL: 0.18 – 0.20; HL: 0.66 – 0.67; HW: 0.63; SL: 0.79 – 0.81; WL: 1.21 – 1.24; GL: 1.22 – 1.41. Indices: BLI: 183 – 185; CI: 94 – 96; REL: 27 – 29; SI: 125 – 128. Moderately sized. Color: Uniformly yellow-brown. Pilosity: most of body covered in moderate to dense pubescence; lacking pubescence on posterior face of propodeum; 4 - 5 small, erect setae on anepisternum. MALE. Measurements (n = 2): TL: 1.95 – 2.14; EL: 0.16; HL: 0.46 – 0.47; HW: 0.41; SL: 0.59 – 0.61; WL: 0.74 – 0.77; GL: 0.75 – 0.90. Indices: BLI: 181 – 189; CI: 86 – 88; REL: 35; SI: 144 – 149. Color: yellow to yellow-brown, with posterior half of head somewhat darker in contrast; metacoxae concolorous with mesosoma. Pilosity: dense pubescence on head, mesoscutum, and mesoscutellum; small patch of pubescence found medially on pronotum, but absent laterally; pubescence sparse to absent on anepisternum, katepisternum, propodeum, and gaster; 1 - 2 small, erect setae on anepisternum. Head: as broad as long; compound eyes surpass lateral margins of head in full-face view; scapes surpass posterior margin of head by about a third of their length. Mesosoma: In profile view, propodeum angled with dorsal face somewhat longer than posterior face. Genitalia: gonopod narrow and triangular, with apex rounded and slightly turned upward (Fig. 71); in ventral view, ventromedial edge of basivolsella lobate and strongly rounded, with cuspis strongly curved dorsally and almost entirely obscured by basivolsella (Fig. 33); gonossiculus mostly straight and more than three times as long as cuspis.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315763258FF692934FCD2F84D.taxon	materials_examined	Other material examined: BELIZE: Cayo, Los Cuevas Field Station, ca. 15 km E Caracol, 16.733 - 88.986 ± 500 m, elev. 581 m, 29. vi. 2019, montane forest, sifted litter, R. S. Anderson # RSA 2019 - 009; Stann Creek, Bocawina, ca. 15 km W Dangriga, 16.927 - 88.397 ± 500 m, elev. 86 m, 3. vii. 2019, rainforest, sifted litter, R. S. Anderson # RSA 2019 - 011; Stann Creek, TREES Field Station, ca. 37 km W Dangriga, 17.05 - 88.57 ± 500 m, elev. 222 m, 25. vi. 2019, 2 ° rainforest, sifted litter, R. S. Anderson # RSA 2019 - 005; COSTA RICA: San José, 8 km S Santa Maria, 9.58121 - 83.9525 ± 1000 m, elev. 1470 m, 30. vi. 2015, cloud forest, Krissy Dominguez # KD 15 - 11 - 09; GUATEMALA: Izabal, 5 km NW Morales, 15.51214 - 88.8662 ± 58 m, elev. 215 m, 18. v. 2009, 2 ° lowland rainforest, sifted litter, LLAMA # Wm-B- 04 - 1 - 10; Izabal, 5 km NW Morales, 15.51077 - 88.8648 ± 38 m, elev. 190 m, 18. v. 2009, 2 ° lowland rainforest, sifted litter, LLAMA # Wm-B- 04 - 2 - 01; Izabal, 5 km NW Morales, 15.5103 - 88.86326 ± 45 m, elev. 170 m, 18. v. 2009, 2 ° lowland rainforest, sifted litter, LLAMA # Wm-B- 04 - 2 - 02; Izabal, 16 km ESE Morales, 15.41307 - 88.70953 ± 30 m, elev. 410 m, 19. v. 2009, 2 ° lowland rainforest, sifted litter, LLAMA # Wm-B- 04 - 2 - 06; Izabal, 16 km ESE Morales, 15.41764 - 88.69683 ± 70 m, elev. 410 m, 19. v. 2009, 2 ° lowland rainforest, sifted litter, LLAMA # Wm-B- 04 - 2 - 09; Petén, Cerro Cahuí, 17.00266 - 89.7187 ± 8 m, elev. 290 m, 21. v. 2009, tropical moist forest at night, sifted litter, LLAMA # Wx-B- 05 - 1 - 01; HONDURAS: Atlántida, 7 km SSW Tela, 15.72521 - 87.452 ± 20 m, elev. 190 m, 15. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wa-C- 08 - 2 - 02; Atlántida, 7 km SSW Tela, 15.72417 - 87.45187 ± 20 m, elev. 190 m, 15. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wa-C- 08 - 2 - 25; Atlántida, 12 km SW La Ceiba, 15.69449 - 86.86436 ± 20 m, elev. 200 m, 19. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wa-C- 09 - 1 - 04; Atlántida, 12 km SW La Ceiba, 15.69449 - 86.86348 ± 20 m, elev. 200 m, 19. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wa-C- 09 - 1 - 23; Atlántida, 12 km SW La Ceiba, 15.69449 - 86.86334 ± 20 m, elev. 200 m, 19. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wa-C- 09 - 1 - 26; Atlántida, 12 km SW La Ceiba, 15.69449 - 86.86279 ± 20 m, elev. 200 m, 19. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wa-C- 09 - 1 - 38; Atlántida, 12 km SW La Ceiba, 15.69108 - 86.86084 ± 20 m, elev. 280 m, 19. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wa-C- 09 - 2 - 24; Atlántida, 12 km SW La Ceiba, 15.69112 - 86.86107 ± 20 m, elev. 280 m, 19. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wa-C- 09 - 2 - 29; Atlántida, 12 km SW La Ceiba, 15.6913 - 86.86138 ± 20 m, elev. 280 m, 19. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wa-C- 09 - 2 - 39; Atlántida, 12 km SW La Ceiba, 15.6916 - 86.86122 ± 20 m, elev. 280 m, 19. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wa-C- 09 - 2 - 47; Atlántida, 12 km SW La Ceiba, 15.69164 - 86.86119 ± 20 m, elev. 280 m, 19. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wa- C- 09 - 2 - 48; Atlántida, 12 km SW La Ceiba, 15.69167 - 86.86116 ± 20 m, elev. 280 m, 19. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wa-C- 09 - 2 - 49; Atlántida, 7 km SSW Tela, 15.72792 - 87.4497 ± 20 m, elev. 120 m, 16. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wm-C- 08 - 1 - 04; Atlántida, 7 km SSW Tela, 15.72792 - 87.4497 ± 20 m, elev. 120 m, 16. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wm-C- 08 - 1 - 05; Atlántida, 10 km SSW Tela, 15.6937377 - 87.47797 ± 20 m, elev. 770 m, 17. vi. 2010, tropical wet forest, sifted litter, LLAMA # Wm-C- 08 - 1 - 09; Atlántida, 10 km SSW Tela, 15.69714 - 87.47451 ± 20 m, elev. 610 m, 17. vi. 2010, tropical wet forest, sifted litter, LLAMA # Wm-C- 08 - 2 - 02; Atlántida, 10 km SSW Tela, 15.69914 - 87.47202 ± 20 m, elev. 520 m, 17. vi. 2010, tropical wet forest, sifted litter, LLAMA # Wm-C- 08 - 2 - 04; Atlántida, 9 km SSW Tela, 15.70207 - 87.47304 ± 20 m, elev. 450 m, 17. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wm-C- 08 - 2 - 05; Atlántida, 9 km SSW Tela, 15.70493 - 87.47291 ± 20 m, elev. 410 m, 17. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wm-C- 08 - 2 - 06; Atlántida, 8 km SSW Tela, 15.70914 - 87.46623 ± 20 m, elev. 330 m, 17. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wm-C- 08 - 2 - 08; Atlántida, 12 km SW La Ceiba, 15.69445 - 86.86338 ± 300 m, elev. 140 m, 19. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wm-C- 09 - 1 - 01; Atlántida, 12 km SW La Ceiba, 15.69445 - 86.86338 ± 300 m, elev. 140 m, 19. vi. 2010, tropical rainforest, sifted litter, LLAMA # Wm-C- 09 - 2 - 01; Comayagua, PN Cerro Azul Meambar, 14.87314 - 87.90297 ± 30 m, elev. 890 m, 22. v. 2010, montane rainforest, sifted litter, LLAMA # Wm-C- 04 - 1 - 07; Comayagua, PN Cerro Azul Meambar, 14.87238 - 87.90332 ± 20 m, elev. 870 m, 22. v. 2010, montane rainforest, sifted litter, LLAMA # Wm-C- 04 - 1 - 08; Comayagua, PN Cerro Azul Meambar, 14.86993 - 87.90479 ± 110 m, elev. 770 m, 21. v. 2010, montane rainforest, sifted litter, LLAMA # Wm-C- 04 - 2 - 01; MEXICO: Chiapas, 13.7 km NW Metzabok, 17.18333 - 91.73333, elev. 540 m, 14. vii. 2007, J. T. Longino # JTL 6046 - s; Chiapas, Lagos de Montebello, Cinco Lagos, 16.1 - 91.66667, elev. 1600 m, 21. vii. 2007, R. S. Anderson # RSA 2007 - 023; Chiapas, 2 km S Playón de la Gloria, 16.13853 - 90.90146 ± 50 m, elev. 170 m, 22. vii. 2007, rainforest, sifted litter, R. S. Anderson # RSA 2007 - 025; Chiapas, 2 km S Playón de la Gloria, 16.13333 - 90.9, elev. 170 m, 22. vii. 2007, R. S. Anderson # RSA 2007 - 026; Chiapas, 2.5 km S Nuevo San Juan Chamula, 16.11667 - 91.45, elev. 750 m, 22. vii. 2007, R. S. Anderson # RSA 2007 - 028; Chiapas, Playón de la Gloria, 16.16095 - 90.90142 ± 50 m, elev. 160 m, 24. vi. 2008, mature wet forest, sifted litter, LLAMA # Wa-A- 09 - 1 - 39; Chiapas, Playón de la Gloria, 16.14721 - 90.89549 ± 50 m, elev. 170 m, 24. vi. 2008, 2 ° wet forest, sifted litter, LLAMA # Wa-A- 09 - 2 - 39; Oaxaca, Cafetal Carlota, 18.04802 - 96.69164 ± 30 m, elev. 1028 m, 12. vi. 2016, liquidambar / cloud forest, sifted litter, R. S. Anderson # RSA 2016 - 136.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315763258FF692934FCD2F84D.taxon	discussion	Notes: Workers of this species exhibit some variability in overall color, ranging from uniformly yellow across most of its range to light brown with somewhat lighter meso- and metacoxae in some specimens collected from Belize. Because of its uniform yellow color, N. cf. docilis most readily resembles N. mosaica and the lighter form N. usul. However, cephalic pubescence is sparse in N. cf. docilis, moderate in N. mosaica, and moderate to dense in N. usul. The gaster is also about the same color as the rest of the body in N. cf. docilis, while in N. mosaica, the gaster is distinctly darker. Compared to all other species examined in this study, N. cf. docilis also has the longest metatibiae relative to its head width (HTI> 125; Fig. 72 D). Nylanderia cf. docilis has a distribution across low to moderate elevation forests from southern Mexico to Honduras.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315723256FF6928CDFC69FA69.taxon	description	Figs. 35 – 37 (worker); Figs. 38 – 39 (queen); Figs. 40 – 43 (male)	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315723256FF6928CDFC69FA69.taxon	materials_examined	Holotype worker, MEXICO: Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.05817 - 96.64624 ± 20 m, elev. 390 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 2 - 36, (USNM: USNMENT 01131154). 5 paratype workers with same locality data as holotype (USNM: USNMENT 01131308, USNMENT 01131309; MNCR: USNMENT 01131310, USNMENT 01131311, USNMENT 01131312). 1 paratype worker, 2 paratype males, and 1 paratype queen, MEXICO: Oaxaca, Uluapan, 4 km NE San BartoloméAyautla, 18.0593 - 96.64624 ± 20 m, elev. 420 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 2 - 13, (USNM: USNMENT 01131339, USNMENT 01131866; MNCR: USNMENT 01131865).	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315723256FF6928CDFC69FA69.taxon	diagnosis	Worker diagnosis: Antennae relatively long, with scapes surpassing posterior margin by nearly half their length; medium to dark reddish-brown and with strongly contrasting whitish meso- and metacoxae; microsculpture very finely matte, causing intense blue iridescence on head, mesosoma, and gaster; erect setae on all parts of body thick, long, and dark; sparse thick erect setae on scapes that strongly contrast with relatively fine appressed pubescence; moderate cephalic pubescence; metatibiae relatively long (HTI> 125).	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315723256FF6928CDFC69FA69.taxon	description	Compare with: N. contraria, N. luceata WORKER. Measurements (n = 12): TL: 1.99 – 2.52; EL: 0.12 – 0.16; EW: 0.09 – 0.12; IOD: 0.29 – 0.33; HE: 0.00 – 0.01; HL: 0.56 – 0.69; HW: 0.46 – 0.55; HLA: 0.17 – 0.25; HLP: 0.25 – 0.29; SL: 0.68 – 0.83; PW: 0.35 – 0.42; MW: 0.18 – 0.28; PrW: 0.24 – 0.31; PDH: 0.22 – 0.25; PTW: 0.11 – 0.15; LHT: 0.60 – 0.76; WL: 0.71 – 0.88; GL: 0.69 – 1.00; SMC: 3 – 6; PMC: 2 – 4; MMC: 2. Indices: BLI: 147 – 162; CI: 80 – 83; EPI: 65 – 87; HTI: 125 – 146; REL: 20 – 24; SI: 143 – 156. Color: medium to dark reddish-brown and with strongly contrasting whitish meso- and metacoxae; black macrosetae strongly contrasting with overall color; overall cuticle with very fine microsculpture, giving cuticle matte appearance and resulting in strong blue iridescence on head, mesosoma, and gaster. Pilosity: erect setae on all parts of body thick, long, and dark; moderate cephalic pubescence, found laterally and concentrated around compound eyes; pubescence sparse to absent between compound eyes; mesosoma pubescence sparse to absent, limited at most to scattered hairs on pronotum and propodeum, and a fringe of hairs concentrated just posterior to the metanotal groove; gaster pubescence sparse to absent; no erect setae on apex of petiole. Head: longer than broad and quadrate with distinct posterolateral corners and flattened posterior margin, with little to no medial emargination; scapes long, surpassing posterior margin by nearly half their length; median ocellus small, but often apparent; lateral ocelli small and often absent or not apparent. Mesosoma: posterior margin of pronotum forming obtuse angle with anterior margin of mesonotum in profile view; propodeum low and evenly rounded, with posterior face about same length as dorsal face. QUEEN. Measurements (n = 1): TL: 3.74; EL: 0.21; HL: 0.71; HW: 0.71; SL: 0.81; WL: 1.18; GL: 1.85. Indices: BLI: 165; CI: 99; REL: 30; SI: 114. Relatively large. Color: Dark brown, with meso- and metacoxae somewhat lighter. Pilosity: most of body covered in moderate to dense pubescence; lacking pubescence on posterior face of propodeum; 1 - 2 small, erect setae on anepisternum. MALE. Measurements (n = 2): TL: 1.98 – 2.06; EL: 0.17 – 0.18; HL: 0.50 – 0.51; HW: 0.44 – 0.45; SL: 0.62 – 0.63; WL: 0.74; GL: 0.74 – 0.82. Indices: BLI: 165 – 167; CI: 87 – 89; REL: 33 – 35; SI: 140 – 142. Color: uniformly medium brown with meso- and metacoxae at most somewhat lighter than mesosoma. Pilosity: dense pubescence on head, mesoscutum, and mesoscutellum; pubescence sparse to absent on pronotum, anepisternum, katepisternum, propodeum, and gaster. Head: as broad as long; compound eyes surpass lateral margins of head in full-face view; scapes surpass posterior margin of head by about half their length. Mesosoma: In profile view, propodeum angled with dorsal face twice as long as posterior face. Genitalia: gonopod triangular and very broad at base, tapering strongly with apex steeply upturned and coming to a point (Fig. 71); in ventral view, ventromedial edge of basivolsella weakly and evenly curved (Fig. 42); gonossiculus straight and nearly three times longer than cuspis.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315723256FF6928CDFC69FA69.taxon	materials_examined	Other material examined: GUATEMALA: Retalhuleu, Finca los Chicharros, SW Zunil, 14.6946 - 91.53792 ± 50 m, elev. 1273 m, 3. vi. 2015, mixed hardwood, sifted litter, R. S. Anderson # RSA 2015 - 102; Zacapa, 2 km SE La Unión, 14.94654 - 89.276 ± 55 m, elev. 1550 m, 12. v. 2009, 2 ° cloud forest, sifted litter, LLAMA # Wm-B- 03 - 1 - 01; Zacapa, 2 km SE La Unión, 14.94758 - 89.27751 ± 28 m, elev. 1530 m, 12. v. 2009, cloud forest, sifted litter, LLAMA # Wm-B- 03 - 1 - 02; Zacapa, 2 km SE La Unión, 14.94654 - 89.276 ± 305 m, elev. 1550 m, 12. v. 2009, cloud forest, sifted litter, LLAMA # Wm-B- 03 - 1 - 06; HONDURAS: Comayagua, Montana Comayagua, 14.53448 - 87.55155 ± 100 m, elev. 1360 m, 16. v. 2009, mixed liquidambar forest, sifted litter, R. S. Anderson # RSA 2009 - 031; Olancho, Parque Nacional La Muralla, 15.0943 - 86.7387 ± 50 m, elev. 1420 m, 2. v. 2010, cloud forest, sifted litter, R. S. Anderson # RSA 2010 - 002; Olancho, Parque Nacional La Muralla, 15.09387 - 86.73934 ± 50 m, elev. 1410 m, 2. v. 2010, cloud forest, sifted litter, R. S. Anderson # RSA 2010 - 003; Olancho, 9 km N Catacamas, 14.93693 - 85.90535 ± 20 m, elev. 1360 m, 10. v. 2010, mixed hardwood forest, sifted litter, R. S. Anderson # RSA 2010 - 020; Comayagua, PN Cerro Azul Meambar, 14.86937 - 87.89583 ± 20 m, elev. 1140 m, 20. v. 2010, ridgetop cloud forest, sifted litter, LLAMA # Wa-C- 04 - 2 - 48; Comayagua, PN Cerro Azul Meambar, 14.86932 - 87.89576 ± 20 m, elev. 1140 m, 20. v. 2010, ridgetop cloud forest, sifted litter, LLAMA # Wa-C- 04 - 2 - 50; Cortés, PN Cusuco, 15.48683 - 88.2343 ± 20 m, elev. 1330 m, 30. v. 2010, mesophyll forest, sifted litter, LLAMA # Wa-C- 06 - 1 - 24; Cortés, PN Cusuco, 15.48683 - 88.23425 ± 20 m, elev. 1330 m, 30. v. 2010, mesophyll forest, sifted litter, LLAMA # Wa-C- 06 - 1 - 25; Cortés, PN Cusuco, 15.48686 - 88.23402 ± 20 m, elev. 1330 m, 30. v. 2010, mesophyll forest, sifted litter, LLAMA # Wa-C- 06 - 1 - 30; Cortés, PN Cusuco, 15.48686 - 88.23398 ± 20 m, elev. 1330 m, 30. v. 2010, mesophyll forest, sifted litter, LLAMA # Wa-C- 06 - 1 - 31; Cortés, PN Cusuco, 15.4894 - 88.2363 ± 20 m, elev. 1290 m, 30. v. 2010, mesophyll forest, sifted litter, LLAMA # Wa-C- 06 - 2 - 14; Cortés, PN Cusuco, 15.4894 - 88.23639 ± 20 m, elev. 1290 m, 30. v. 2010, mesophyll forest, sifted litter, LLAMA # Wa-C- 06 - 2 - 16; Cortés, PN Cusuco, 15.48932 - 88.23752 ± 20 m, elev. 1290 m, 30. v. 2010, mesophyll forest, sifted litter, LLAMA # Wa-C- 06 - 2 - 43; Cortés, PN Cusuco, 15.48915 - 88.23745 ± 20 m, elev. 1290 m, 30. v. 2010, mesophyll forest, sifted litter, LLAMA # Wa-C- 06 - 2 - 47; Olancho, PN La Muralla, 15.09734 - 86.73912 ± 20 m, elev. 1490 m, 2. v. 2010, cloud forest, sifted litter, LLAMA # Wm-C- 01 - 1 - 01; Olancho, PN La Muralla, 15.09803 - 86.7399 ± 20 m, elev. 1500 m, 2. v. 2010, cloud forest, sifted litter, LLAMA # Wm-C- 01 - 1 - 02; Olancho, PN La Muralla, 15.09859 - 86.74216 ± 10 m, elev. 1510 m, 2. v. 2010, cloud forest, sifted litter, LLAMA # Wm-C- 01 - 1 - 03; Olancho, PN La Muralla, 15.09911 - 86.74067 ± 125 m, elev. 1530 m, 2. v. 2010, cloud forest, sifted litter, LLAMA # Wm-C- 01 - 1 - 05; Olancho, PN La Muralla, 15.09489 - 86.73944 ± 125 m, elev. 1420 m, 2. v. 2010, cloud forest, sifted litter, LLAMA # Wm-C- 01 - 2 - 01; Comayagua, PN Cerro Azul Meambar, 14.87112 - 87.89938 ± 300 m, elev. 1100 m, 20. v. 2010, ridgetop cloud forest, sifted litter, LLAMA # Wm-C- 04 - 1 - 01; Comayagua, PN Cerro Azul Meambar, 14.86951 - 87.89701 ± 300 m, elev. 1150 m, 20. v. 2010, ridgetop cloud forest, sifted litter, LLAMA # Wm-C- 04 - 1 - 02; Comayagua, PN Cerro Azul Meambar, 14.87236 - 87.90098 ± 20 m, elev. 1040 m, 22. v. 2010, cloud forest, sifted litter, LLAMA # Wm-C- 04 - 1 - 05; Comayagua, PN Cerro Azul Meambar, 14.87209 - 87.90187 ± 20 m, elev. 1000 m, 22. v. 2010, montane rainforest, sifted litter, LLAMA # Wm-C- 04 - 1 - 06; Comayagua, PN Cerro Azul Meambar, 14.87314 - 87.90297 ± 30 m, elev. 890 m, 22. v. 2010, montane rainforest, sifted litter, LLAMA # Wm-C- 04 - 1 - 07; Comayagua, PN Cerro Azul Meambar, 14.87238 - 87.90332 ± 20 m, elev. 870 m, 22. v. 2010, montane rainforest, sifted litter, LLAMA # Wm-C- 04 - 1 - 08; Comayagua, PN Cerro Azul Meambar, 14.86993 - 87.90479 ± 110 m, elev. 770 m, 21. v. 2010, montane rainforest, sifted litter, LLAMA # Wm-C- 04 - 2 - 01; Atlántida, 10 km SSW Tela, 15.69652 - 87.47636 ± 20 m, elev. 660 m, 17. vi. 2010, tropical wet forest, sifted litter, LLAMA # Wm- C- 08 - 2 - 01; MEXICO: Puebla, 1.4 km WSW Hueytamalco, 19.93725 - 97.30273 ± 50 m, elev. 760 m, 12. vi. 2019, mesophyl forest, sifted litter, J. T. Longino # JTL 10644 - s; Veracruz, 10 km NNW Sontecomapan, 18.58333 - 95.08333 ± m, elev. 500 m, 21. iii. 1985, rainforest, P. S. Ward # PSW 7369 - 41; Veracruz, 10 km NNW Sontecomapan, 18.58333 - 95.08333 ± m, elev. 500 m, 21. iii. 1985, rainforest, sifted litter, P. S. Ward # PSW 7369 - 41; Veracruz, Road to Ruiz Cortinez, 18.51999 - 95.16196 ± 30 m, elev. 1054 m, 5. vi. 2016, liquidambar forest, sifted litter, R. S. Anderson # RSA 2016 - 104; Veracruz, Road to Ruiz Cortinez, 18.5229 - 95.15441 ± 30 m, elev. 1114 m, 5. vi. 2016, mixed hardwood forest, sifted litter, R. S. Anderson # RSA 2016 - 105; Veracruz, hills above Ruiz Cortinez, 18.5304 - 95.14127 ± 30 m, elev. 1239 m, 7. vi. 2016, hilltop hardwood forest, sifted litter, R. S. Anderson # RSA 2016 - 110; Oaxaca, Cafetal Carlota, 18.04756 - 96.69252 ± 30 m, elev. 1011 m, 12. vi. 2016, liquidambar / cloud forest, sifted litter, R. S. Anderson # RSA 2016 - 138; Oaxaca, Cafetal Carlota, 18.04773 - 96.68953 ± 30 m, elev. 1041 m, 14. vi. 2016, liquidambar / cloud forest, sifted litter, R. S. Anderson # RSA 2016 - 145; Oaxaca, Cafetal Carlota, 18.04784 - 96.69198 ± 30 m, elev. 1019 m, 14. vi. 2016, liquidambar / cloud forest, sifted litter, R. S. Anderson # RSA 2016 - 146; Oaxaca, Cafetal Carlota, 18.04791 - 96.69076 ± 30 m, elev. 1035 m, 14. vi. 2016, liquidambar / cloud forest, sifted litter, R. S. Anderson # RSA 2016 - 147; Veracruz, Est. Biol. Los Tuxtlas, 18.5863 - 95.07665 ± 20 m, elev. 180 m, 29. v. 2016, tropical rainforest, sifted litter, ADMAC # Wa-F- 01 - 2 - 17; Veracruz, Est. Biol. Los Tuxtlas, 18.58557 - 95.07665 ± 20 m, elev. 180 m, 29. v. 2016, tropical rainforest, sifted litter, ADMAC # Wa-F- 01 - 2 - 33; Veracruz, Est. Biol. Los Tuxtlas, 18.58539 - 95.07665 ± 20 m, elev. 180 m, 29. v. 2016, tropical rainforest, sifted litter, ADMAC # Wa-F- 01 - 2 - 37; Veracruz, Ruiz Cortínez, 12 km NE San Andrés Tuxtla, 18.53399 - 95.14888 ± 20 m, elev. 1130 m, 3. vi. 2016, montane wet forest, sifted litter, ADMAC # Wa-F- 02 - 1 - 10; Veracruz, Ruiz Cortínez, 12 km NE San Andrés Tuxtla, 18.53412 - 95.14974 ± 20 m, elev. 1130 m, 3. vi. 2016, montane wet forest, sifted litter, ADMAC # Wa-F- 02 - 1 - 27; Veracruz, Ruiz Cortínez, 12 km NE San Andrés Tuxtla, 18.53399 - 95.14765 ± 20 m, elev. 1130 m, 3. vi. 2016, montane wet forest, sifted litter, ADMAC # Wa- F- 02 - 1 - 44; Veracruz, Ruiz Cortínez, 12 km NE San Andrés Tuxtla, 18.53399 - 95.14734 ± 20 m, elev. 1130 m, 3. vi. 2016, montane wet forest, sifted litter, ADMAC # Wa-F- 02 - 1 - 50; Veracruz, Ruiz Cortínez, 12 km NE San Andrés Tuxtla, 18.53231 - 95.14302 ± 20 m, elev. 1130 m, 3. vi. 2016, montane wet forest, sifted litter, ADMAC # Wa-F- 02 - 2 - 23; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.06001 - 96.64345 ± 20 m, elev. 430 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 1 - 02; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.06001 - 96.6435 ± 20 m, elev. 430 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 1 - 03; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.06001 - 96.64355 ± 20 m, elev. 430 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 1 - 04; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.06001 - 96.64458 ± 20 m, elev. 430 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 1 - 24; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.06001 - 96.64463 ± 20 m, elev. 430 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 1 - 25; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.05957 - 96.64579 ± 20 m, elev. 430 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 2 - 02; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.05952 - 96.64588 ± 20 m, elev. 430 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 2 - 04; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.05939 - 96.64615 ± 20 m, elev. 420 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 2 - 10; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.05936 - 96.64619 ± 20 m, elev. 420 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 2 - 11; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.05934 - 96.64624 ± 20 m, elev. 420 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 2 - 12; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.05925 - 96.64624 ± 20 m, elev. 420 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 2 - 14; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.05889 - 96.64624 ± 20 m, elev. 410 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 2 - 22; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.05866 - 96.64624 ± 20 m, elev. 400 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 2 - 25; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.0583 - 96.64624 ± 20 m, elev. 400 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 2 - 33; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.05821 - 96.64624 ± 20 m, elev. 390 m, 9. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wa-F- 03 - 2 - 35; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.0486 - 96.69106 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 1 - 39; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.0486 - 96.69127 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 1 - 43; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.0486 - 96.69147 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa- F- 04 - 1 - 47; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04736 - 96.6903 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 01; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04745 - 96.69018 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 04; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04753 - 96.69006 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 07; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04762 - 96.68995 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 10; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04804 - 96.68954 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 24; Oaxaca, Cafetal Carlota, 3 km NW Ayautla, 18.04807 - 96.68957 ± 20 m, elev. 1040 m, 13. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wa-F- 04 - 2 - 25; Veracruz, Est. Biol. Los Tuxtlas, 18.5862 - 95.07964 ± 20 m, elev. 260 m, 30. v. 2016, tropical rainforest, sifted litter, ADMAC # Wm-F- 01 - 1 - 02; Veracruz, Est. Biol. Los Tuxtlas, 18.583 - 95.08223 ± 20 m, elev. 360 m, 30. v. 2016, tropical rainforest, sifted litter, ADMAC # Wm-F- 01 - 1 - 04; Veracruz, 8 km NNE Soteapan, 18.30208 - 94.85354 ± 20 m, elev. 1020 m, 30. v. 2016, liquidamber-oak forest, sifted litter, ADMAC # Wm-F- 01 - 1 - 07; Veracruz, Ruiz Cortínez, 12 km NE San Andrés Tuxtla, 18.53456 - 95.13976 ± 20 m, elev. 1070 m, 2. vi. 2016, montane wet forest, sifted litter, ADMAC # Wm-F- 02 - 1 - 01; Veracruz, Volcan San Martín, 18.53438 - 95.19025 ± 20 m, elev. 1020 m, 5. vi. 2016, mature forest edge near pasture, sifted litter, ADMAC # Wm-F- 02 - 1 - 04; Veracruz, Volcan San Martín, 18.54332 - 95.19177 ± 20 m, elev. 1110 m, 5. vi. 2016, mature wet forest, sifted litter, ADMAC # Wm-F- 02 - 1 - 05; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.05845 - 96.64414 ± 20 m, elev. 380 m, 8. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wm-F- 03 - 1 - 01; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.05678 - 96.64841 ± 20 m, elev. 540 m, 8. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wm- F- 03 - 1 - 02; Oaxaca, Uluapan, 4 km NE San Bartolomé Ayautla, 18.06188 - 96.64635 ± 20 m, elev. 640 m, 11. vi. 2016, lowland rainforest, sifted litter, ADMAC # Wm-F- 03 - 1 - 05; Oaxaca, 8 km E Huautla, 18.11663 - 96.7695 ± 20 m, elev. 1380 m, 15. vi. 2016, 2 ° liquidambar forest, sifted litter, ADMAC # Wm-F- 04 - 1 - 10; Oaxaca, 10 km ENE Huautla, 18.15269 - 96.75035 ± 20 m, elev. 1150 m, 15. vi. 2016, vegetated karst pinnacle, sifted litter, ADMAC # Wm-F- 04 - 2 - 01; Puebla, Cascada Las Brisas, 2 km SE Cuetzalan, 20.00549 - 97.50801 ± 20 m, elev. 930 m, 2. vii. 2016, montane wet forest, sifted litter, ADMAC # Wm-F- 08 - 1 - 02; Puebla, Cascada Las Brisas, 2 km SE Cuetzalan, 20.00545 - 97.50789 ± 20 m, elev. 930 m, 2. vii. 2016, montane wet forest, sifted litter, ADMAC # Wm-F- 08 - 1 - 03; Puebla, Presa La Soledad; 11 km SE Cuetzalan, 19.96599 - 97.45082 ± 20 m, elev. 760 m, 3. vii. 2016, mixed pine-hardwood forest, sifted litter, ADMAC # Wm-F- 08 - 1 - 04; NICARAGUA: Matagalpa, RN Cerro Musún, 12.97283 - 85.23419 ± 50 m, elev. 1170 m, 2. v. 2011, wet montane forest, sifted litter, R. S. Anderson # RSA 2011 - 011; Matagalpa, RN Cerro Musún, 12.97608 - 85.23299 ± 50 m, elev. 1250 m, 2. v. 2011, wet montane forest, sifted litter, R. S. Anderson # RSA 2011 - 012; Jinotega, PN Cerro Saslaya, 13.77172 - 85.01277 ± 10 m, elev. 1110 m, 12. v. 2011, ridgetop cloud forest, sifted litter, LLAMA # Wa-D- 03 - 1 - 05; Jinotega, PN Cerro Saslaya, 13.76689 - 85.02472 ± 10 m, elev. 1040 m, 12. v. 2011, montane wet forest, sifted litter, LLAMA # Wa-D- 03 - 2 - 10; Jinotega, PN Cerro Saslaya, 13.76749 - 85.02452 ± 13 m, elev. 1040 m, 12. v. 2011, montane wet forest, sifted litter, LLAMA # Wa-D- 03 - 2 - 24; Jinotega, PN Cerro Saslaya, 13.76792 - 85.02438 ± 10 m, elev. 1040 m, 12. v. 2011, montane wet forest, sifted litter, LLAMA # Wa- D- 03 - 2 - 34; Jinotega, PN Cerro Saslaya, 13.76818 - 85.02429 ± 10 m, elev. 1040 m, 12. v. 2011, montane wet forest, sifted litter, LLAMA # Wa-D- 03 - 2 - 40; Jinotega, RN Datanlí El Diablo, 13.10417 - 85.86806 ± 10 m, elev. 1400 m, 18. v. 2011, cloud forest, sifted litter, LLAMA # Wa-D- 04 - 2 - 14; Jinotega, RN Datanlí El Diablo, 13.10436 - 85.86787 ± 10 m, elev. 1400 m, 18. v. 2011, cloud forest, sifted litter, LLAMA # Wa-D- 04 - 2 - 20; Jinotega, RN Datanlí El Diablo, 13.10474 - 85.86748 ± 10 m, elev. 1400 m, 18. v. 2011, cloud forest, sifted litter, LLAMA # Wa-D- 04 - 2 - 32; Jinotega, RN Cerro Kilambé, 13.56942 - 85.69745 ± 10 m, 1500 m, 23. v. 2011, cloud forest, sifted litter, LLAMA # Wa-D- 05 - 1 - 07; Jinotega, RN Cerro Kilambé, 13.56755 - 85.69695 ± 10 m, elev. 1420 m, 23. v. 2011, cloud forest, sifted litter, LLAMA # Wa-D- 05 - 2 - 06; Jinotega, RN Cerro Kilambé, 13.56746 - 85.69746 ± 10 m, elev. 1400 m, 23. v. 2011, cloud forest, sifted litter, LLAMA # Wa-D- 05 - 2 - 18; Jinotega, RN Cerro Kilambé, 13.56745 - 85.69676 ± 10 m, elev. 1440 m, 23. v. 2011, cloud forest, sifted litter, LLAMA # Wa-D- 05 - 2 - 32; Jinotega, RN Cerro Kilambé, 13.56747 - 85.69667 ± 10 m, elev. 1440 m, 23. v. 2011, cloud forest, sifted litter, LLAMA # Wa-D- 05 - 2 - 34; Jinotega, RN Cerro Kilambé, 13.5675 - 85.69644 ± 15 m, elev. 1440 m, 23. v. 2011, cloud forest, sifted litter, LLAMA # Wa-D- 05 - 2 - 39; Jinotega, RN Cerro Kilambé, 13.56751 - 85.6964 ± 10 m, elev. 1440 m, 23. v. 2011, cloud forest, sifted litter, LLAMA # Wa-D- 05 - 2 - 40; Jinotega, RN Cerro Kilambé, 13.56754 - 85.69621 ± 10 m, elev. 1440 m, 23. v. 2011, cloud forest, sifted litter, LLAMA # Wa-D- 05 - 2 - 44; Jinotega, PN Cerro Saslaya, 13.771 - 85.02538 ± 30 m, elev. 1140 m, 13. v. 2011, montane wet forest, sifted litter, LLAMA # Wm-D- 03 - 2 - 08; Jinotega, RN Datanlí El Diablo, 13.10754 - 85.86831 ± 40 m, elev. 1450 m, 19. v. 2011, cloud forest, sifted litter, LLAMA # Wm-D- 04 - 1 - 07; Jinotega, RN Datanlí El Diablo, 13.10436 - 85.86787 ± 150 m, elev. 1400 m, 18. v. 2011, cloud forest, sifted litter, LLAMA # Wm-D- 04 - 2 - 01; Nueva Segovia, 9 km NW Jalapa, 13.97735 - 86.18887 ± 20 m, elev. 1420 m, 29. v. 2011, oak cloud forest, sifted litter, LLAMA # Wm- D- 06 - 1 - 05.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315723256FF6928CDFC69FA69.taxon	etymology	Etymology: The species epithet is derived from ‘ lazulum ’ (L. = sky), referring to the intensity of the brilliant blue iridescence found across the entire cuticle of this species.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315723256FF6928CDFC69FA69.taxon	discussion	Notes: Nylanderia lazulina workers have whitish meso- and metacoxae like those of N. contraria and N. luceata but are otherwise distinct and not likely to be confused with other species. Unlike all other species, it is medium to dark reddish brown with dense microsculpture that gives the overall surface of the cuticle a matte appearance. It also has a very strong blue iridescence, perhaps more intense than any other known Nylanderia species. This species is primarily found in moderate to high elevation forests ranging from Veracruz, Mexico to Nicaragua (Fig. 2 B), and is relatively common across this range compared to other Nylanderia species.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823157F3250FF692DB4FAC1FA8B.taxon	description	Figs. 44 – 46 (worker); Figs. 47 – 48 (queen)	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823157F3250FF692DB4FAC1FA8B.taxon	materials_examined	Holotype worker, HONDURAS: Cortés, PN Cusuco, 15.48572 - 88.23746 ± 60 m, elev. 1210 m, 31. v. 2010, mesophyll forest, sifted litter, LLAMA # Wm-C- 06 - 2 - 04 (USNM: USNMENT 01131824). 5 paratype workers and 1 paratype queen with same locality data as holotype (USNM: USNMENT 01131241, USNMENT 01131816, USNMENT 01131817, USNMENT 01131867; MNCR: USNMENT 01131821, USNMENT 01131822).	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823157F3250FF692DB4FAC1FA8B.taxon	diagnosis	Worker diagnosis: Antennae relatively short, with scapes surpassing posterior margin by less than a quarter of their length; light to medium reddish-brown and with meso- and metacoxae lighter than mesosoma; microsculpture and blue iridescence subtle, most visible on head; moderate cephalic pubescence. Compare with: N. contraria, N. lazulina	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823157F3250FF692DB4FAC1FA8B.taxon	description	WORKER. Measurements (n = 8): TL: 1.71 – 2.24; EL: 0.09 – 0.11; EW: 0.08 – 0.09; IOD: 0.31 – 0.34; HE: 0.00 – 0.02; HL: 0.53 – 0.61; HW: 0.45 – 0.51; HLA: 0.18 – 0.21; HLP: 0.25 – 0.29; SL: 0.56 – 0.62; PW: 0.31 – 0.37; MW: 0.17 – 0.20; PrW: 0.24 – 0.28; PDH: 0.18 – 0.23; PTW: 0.11 – 0.13; LHT: 0.50 – 0.55; WL: 0.62 – 0.72; GL: 0.55 – 0.96; SMC: 9 – 13; PMC: 2 – 4; MMC: 2 – 3. Indices: BLI: 131 – 146; CI: 83 – 87; EPI: 71 – 78; HTI: 106 – 112; REL: 17 – 19; SI: 119 – 129. Color: light to medium reddish-brown with antennae, mandibles, leg joints, and tarsi yellow to yellow-brown in contrast to body; meso-and metacoxae yellow to whitish and lighter than mesosoma; overall cuticle lightly microsculptured, resulting in subtle blue iridescence on head, mesosoma, and gaster. Pilosity: erect macrosetae on all parts of body thick, long, and dark; moderate cephalic pubescence, found laterally and concentrated around compound eyes; pubescence sparse to absent between compound eyes; mesosoma pubescence sparse to absent, limited at most to scattered hairs on pronotum and propodeum, and a fringe of hairs concentrated just posterior to the metanotal groove; gaster pubescence sparse to absent; pair of small, erect setae on apex of petiole. Head: longer than broad and quadrate with distinct posterolateral corners and flattened posterior margin, with slight to moderate medial emargination; scapes surpass posterior margin of head by less than a quarter of their length; compound eyes relatively small (REL: <19); median ocellus small, but often apparent; lateral ocelli absent or not apparent. Mesosoma: posterior margin of pronotum forming obtuse angle with anterior margin of mesonotum in profile view; propodeum low and evenly rounded, with posterior face about same length as dorsal face. QUEEN. Measurements (n = 1): TL: 3.98; EL: 0.23; HL: 0.77; HW: 0.72; SL: 0.91; WL: 1.41; GL: 1.80. Indices: BLI: 183; CI: 94; REL: 30; SI: 126. Relatively large. Color: uniformly medium reddish-brown. Pilosity: most body covered in moderate to dense pubescence; lacking pubescence on posterior face of propodeum; 1 - 2 small, erect setae on anepisternum.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823157F3250FF692DB4FAC1FA8B.taxon	materials_examined	Other material examined: GUATEMALA: San Marcos, Bojonal Road, 14.94786 - 91.8837 ± 50 m, elev. 1618 m, 4. vi. 2015, cloud forest, leaf litter, R. S. Anderson # RSA 2015 - 105; MEXICO: Chiapas, 5 km NE Coapilla, 17.17602 - 93.13293 ± 300 m, elev. 1990 m, 25. v. 2008, mesophil forest, leaf litter, LLAMA # Wm-A- 04 - 1.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823157F3250FF692DB4FAC1FA8B.taxon	etymology	Etymology: The species epithet is derived from ‘ luceo ’ (L. = to shine).	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823157F3250FF692DB4FAC1FA8B.taxon	discussion	Notes: Nylanderia luceata workers, like those of N. lazulina and N. contraria, have whitish meso- and metacoxae that strongly contrast with the color of the mesosoma. However, the body of N. luceata is lighter in overall color, its cuticle is much less microsculptured, and its blue iridescence is much more subtle than both of those species .. Unlike N. contraria, both this species and N. lazulina have only moderate cephalic pubescence, existing mostly as patches around the compound eyes and absent to sparse medially (Fig. 4 B). Though subtle, the compound eyes of N. luceata are often slightly smaller than those of all other species in examined in this study. Nylanderia luceata is found in high elevation forests ranging from Chiapas in southern Mexico to the western edge of Honduras (Fig. 2 B).	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315793252FF692D8BFE18FD05.taxon	description	Figs. 49 – 51 (worker)	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315793252FF692D8BFE18FD05.taxon	materials_examined	Holotype worker, GUATEMALA: Zacapa, 2 km SE La Unión, 14.95039 - 89.27894 ± 53 m, elev. 1440 m, cloud forest, sifted litter, 12. v. 2009, cloud forest, sifted litter, LLAMA # Wm-B- 03 - 1 - 04 (USNM: USNMENT 01131331). 8 paratype workers with same localitydataasholotype (USNM: USNMENT 01131210, USNMENT 01131328, USNMENT 01131329, USNMENT 01131330, USNMENT 01131332; MNCR: USNMENT 01131876, USNMENT 01131877, USNMENT 01131878).	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315793252FF692D8BFE18FD05.taxon	diagnosis	Worker diagnosis: Antennae relatively long, with scapes surpassing posterior margin by nearly half their length; medium to dark reddish-brown with yellow to yellow-brown mandibles, antennae, and leg; meso-and metacoxae about same color or somewhat lighter than mesosoma; moderate to fine cuticular microsculpture resulting in moderate to strong blue iridescence on head, mesosoma, and gaster; erect setae on scapes long and dark, strongly contrasting with appressed pubescence; moderate cephalic pubescence; metatibiae relatively long (HTI> 125). Compare with: N. mosaica, N. usul.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315793252FF692D8BFE18FD05.taxon	description	WORKER. Measurements (n = 6): TL: 2.16 – 2.52; EL: 0.12 – 0.14; EW: 0.10 – 0.11; IOD: 0.32 – 0.35; HE: 0.00 – 0.01; HL: 0.59 – 0.63; HW: 0.48 – 0.53; HLA: 0.20 – 0.23; HLP: 0.24 – 0.28; SL: 0.70 – 0.75; PW: 0.36 – 0.40; MW: 0.19 – 0.21; PrW: 0.28 – 0.31; PDH: 0.19 – 0.26; PTW: 0.12 – 0.13; LHT: 0.64 – 0.68; WL: 0.77 – 0.83; GL: 0.71 – 1.07; SMC: 11 – 13; PMC: 2 – 3; MMC: 2. Indices: BLI: 151 – 160; CI: 82 – 85; EPI: 76 – 95; HTI: 127 – 134; REL: 20 – 23; SI: 140 – 146. Color: medium to dark reddish-brown with yellow to yellow-brown mandibles, antennae, and leg joints; meso-and metacoxae about same color or somewhat lighter than mesosoma; overall cuticle moderately to finely microsculptured, resulting in moderate to strong blue iridescence on head, mesosoma, and gaster. Pilosity: erect macrosetae on scapes abundant, long, and dark, strongly contrasting with fine, appressed pubescence; moderate cephalic pubescence, found laterally and concentrated around compound eyes; pubescence sparse to absent between compound eyes; mesosoma pubescence sparse to absent, limited at most to scattered hairs on pronotum and propodeum, and a fringe of hairs concentrated just posterior to the metanotal groove; gaster pubescence sparse to absent; pair of small, erect setae on apex of petiole. Head: longer than broad and quadrate with distinct posterolateral corners and flattened posterior margin, with little to no medial emargination; scapes long, surpassing posterior margin by nearly half their length; median ocellus small, but often apparent; lateral ocelli absent or not apparent. Mesosoma: promesonotal area evenly convex in profile view, with posterior margin of pronotum continuous or nearly continuous with anterior margin of mesonotum; propodeum low and evenly rounded, with posterior face at most slightly longer than dorsal face.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315793252FF692D8BFE18FD05.taxon	etymology	Etymology: The species epithet is derived from ‘ mendax ’ (L. = deceptive), referring to the species’ strong morphological similarity to N. usul.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC282315793252FF692D8BFE18FD05.taxon	discussion	Notes: Nylanderia mendax workers most strongly resemble those of N. usul and are also somewhat like those of N. mosaica. This species’ overall color, which is medium to dark reddish-brown, is much different than that of N. mosaica, which is overall yellow to yellow-brown with a medium to dark brown gaster. Both N. usul and N. mendax also tend to be larger in overall body size than N. mosaica. Nylanderia mendax is most readily separable from N. usul by the relative length of its scapes, which surpass the posterior margin of the head by nearly half their length. In N. usul, the scapes are much shorter, only surpassing the posterior margin by a quarter to a third of their length. Nylanderia mendax is known from only one locality in Zacapa, Guatemala (Fig. 2 B), where it occurs in high elevation cloud forest.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823157B326CFF692B18FE52FC14.taxon	description	Figs. 52 – 54 (worker); Figs. 55 – 56 (queen)	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823157B326CFF692B18FE52FC14.taxon	materials_examined	Holotype worker, COSTA RICA: Alajuela, 10 km E of Monteverde, 10.30971 - 84.72004, ± 50 m, elev. 890 m, wet forest, sifted litter, 18. v. 2014, J. T. Longino # JTL 8692 - s (USNM: USNMENT 01131335). 1 paratype worker and 1 paratype queen with same locality data as holotype (USNM: USNMENT 01130940, USNMENT 01131335). 3 paratype workers, COSTA RICA: San José, Cerro Plano, 9.48264 - 83.96259 ± 10 m, elev. 1070 m, 4. vii. 2015, ridgetop cloud forest, isolated peak with oak trees, leaf litter, ADMAC # Wa-E- 06 - 2 - 25 (MNCR: USNMENT 01131333, USNMENT 01131334, USNMENT 01131848).	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823157B326CFF692B18FE52FC14.taxon	diagnosis	Worker diagnosis: Antennae relatively short, with scapes surpassing posterior margin by about a quarter of their length; bicolored, with yellow to yellow-brown head and mesosoma and medium to dark brown gaster; meso- and metacoxae yellow and at most somewhat lighter than mesosoma; light cuticular microsculpture resulting in subtle blue iridescence on head, mesosoma, and gaster; moderate cephalic pubescence. Compare with: N. mendax, N. usul	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823157B326CFF692B18FE52FC14.taxon	description	WORKER. Measurements (n = 9): TL: 1.70 – 2.01; EL: 0.09 – 0.12; EW: 0.07 – 0.10; IOD: 0.30 – 0.34; HE: 0.00 – 0.01; HL: 0.52 – 0.57; HW: 0.42 – 0.49; HLA: 0.18 – 0.20; HLP: 0.23 – 0.27; SL: 0.59 – 0.65; PW: 0.32 – 0.36; MW: 0.17 – 0.19; PrW: 0.24 – 0.28; PDH: 0.17 – 0.30; PTW: 0.10 – 0.14; LHT: 0.50 – 0.56; WL: 0.60 – 0.70; GL: 0.58 – 0.76; SMC: 9 – 12; PMC: 2 – 3; MMC: 2 – 3. Indices: BLI: 139 – 148; CI: 82 – 88; EPI: 72 – 81; HTI: 112 – 119; REL: 17 – 21; SI: 127 – 139. Color: bicolored, with yellow to yellow-brown head and mesosoma and medium to dark brown gaster; black macrosetae strongly contrasting with overall color; meso- and metacoxae yellow and at most somewhat lighter than mesosoma; overall cuticle lightly microsculptured, resulting in subtle blue iridescence on head, mesosoma, and gaster. Pilosity: erect macrosetae on scapes abundant, long, and dark, strongly contrasting with fine, appressed pubescence; moderate cephalic pubescence, found laterally and concentrated around compound eyes; pubescence sparse to absent between compound eyes; mesosoma pubescence sparse to absent, limited at most to scattered hairs on pronotum and propodeum, and a fringe of hairs concentrated just posterior to the metanotal groove; gaster pubescence sparse to absent; pair of small, erect setae on apex of petiole. Head: longer than broad and quadrate with distinct posterolateral corners and flattened posterior margin, with little to no medial emargination; scapes surpass posterior margin of head by about a quarter of their length; all three ocelli absent or not apparent. Mesosoma: posterior margin of pronotum forming obtuse angle with anterior margin of mesonotum in profile view; propodeum low and evenly rounded, with posterior face about same length as dorsal face. QUEEN. Measurements (n = 1): TL: 3.51; EL: 0.21; HL: 0.68; HW: 0.68; SL: 0.80; WL: 1.29; GL: 1.54. Indices: BLI: 190; CI: 99; REL: 30; SI: 119. Moderately sized. Color: bicolored, with light yellow-brown mesosoma and medium to dark yellow-brown head and gaster; meso- and metacoxae concolorous with mesosoma. Pilosity: most of body covered in moderate to dense pubescence; lacking pubescence laterally on pronotum, on most of anepisternum except for dorsal edge, and posterior face of propodeum; 8 - 10 small, erect setae on anepisternum.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823157B326CFF692B18FE52FC14.taxon	materials_examined	Other material examined: COSTA RICA: San José, Cerro Plano, 9.48264 - 83.96259 ± 10 m, elev. 1070 m, 4. vii. 2015, ridgetop cloud forest, isolated peak with oak trees, leaf litter, ADMAC # Wa-E- 06 - 2 - 25; Cartago, PN Tapantí, 9.73699 - 83.78176 ± 20 m, elev. 1330 m, 6. vi. 2015, cloud forest, old 2 nd growth, riparian, leaf litter, ADMAC # Wm-E- 01 - 1 - 02.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823157B326CFF692B18FE52FC14.taxon	etymology	Etymology: The species epithet is derived from ‘ musaicum ’ (L. = mosaic), referring to this species’ bicolored appearance.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC2823157B326CFF692B18FE52FC14.taxon	discussion	Notes: Nylanderia mosaica workers most strongly resemble those of N. mendax and N. usul in appearance, though N. mosaica workers are easily separable based on their relatively small body size and bicolored appearance, with a yellow to yellow-brown head and mesosoma and medium to dark brown gaster. This species is only known to moderate to high elevation forests in Costa Rica (Fig. 2 B), where it is sympatric with only N. usul and no other species in American Clade I.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231545326EFF692C6BFD6DFB53.taxon	description	Figs. 57 – 59 (worker); Figs. 60 – 61 (queen)	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231545326EFF692C6BFD6DFB53.taxon	materials_examined	Holotype worker, MEXICO: Veracruz, 8 km WSW of Xalapa, 19.52081 - 96.9917 ± 20 m, elev. 1530 m, cloud forest, leaf litter (MiniWinkler), 22. vi. 2016, ADMAC # Wa-F- 05 - 1 - 41 (USNM: USNMENT 01131180); 4 paratype workers with same locality data as holotype (USNM: USNMENT 01131313, USNMENT 01131314; MNCR: USNMENT 01131315, USNMENT 01131316). 1 paratype queen, MEXICO: Veracruz, 8 km WSW of Xalapa, 19.52283 - 96.99102 ± 20 m, elev. 1500 m, cloud forest, leaf litter (MiniWinkler), 22. vi. 2016, ADMAC # Wa-F- 05 - 2 - 31 (USNM: USNMENT 01131789).	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231545326EFF692C6BFD6DFB53.taxon	diagnosis	Worker diagnosis: Antennae relatively short, with scapes surpassing posterior margin of head by about a third of their length; medium to dark brown with antennae, mandibles, leg joints, and tarsi yellow in contrast to body; meso-and metacoxae somewhat lighter than mesosoma; entire cuticle smooth and shiny, with microsculpture, and completely lacking blue iridescence; dense cephalic pubescence; posterior margin of head with little to no emargination. Compare with: N. austroccidua, N. contraria	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231545326EFF692C6BFD6DFB53.taxon	description	WORKER. Measurements (n = 10): TL: 1.81 – 2.13; EL: 0.09 – 0.12; EW: 0.08 – 0.10; IOD: 0.29 – 0.32; HE: 0.01; HL: 0.52 – 0.58; HW: 0.44 – 0.49; HLA: 0.18 – 0.20; HLP: 0.26 – 0.28; SL: 0.31 – 0.35; PW: 0.31 – 0.35; MW: 0.17 – 0.20; PrW: 0.24 – 0.32; PDH: 0.17 – 0.22; PTW: 0.09 – 0.16; LHT: 0.49 – 0.53; WL: 0.59 – 0.68; GL: 0.64 – 0.94; SMC: 7 – 10; PMC: 2 – 3; MMC: 2. Indices: BLI: 130 – 149; CI: 79 – 86; EPI: 67 – 72; HTI: 109 – 116; REL: 18 – 22; SI: 122 – 129. Color: medium to dark brown with yellow to yellow-brown antennae, mandibles, and tarsi; meso- and metacoxae often somewhat lighter than mesosoma but sometimes concolorous; overall cuticle smooth and shiny, with no cuticular microsculpture and no blue iridescence Pilosity: dense cephalic pubescence covering all surfaces of head in full-face view; mesosoma pubescence sparse to absent, limited at most to scattered hairs on pronotum and propodeum, and a fringe of hairs concentrated just posterior to the metanotal groove; gaster pubescence sparse to absent; pair of small, erect setae on apex of petiole. Head: longer than broad and quadrate with distinct posterolateral corners and flattened posterior margin, with little to no medial emargination; scapes surpass posterior margin of head by about a third of their length; median ocellus small, but often apparent; lateral ocelli absent or not apparent. Mesosoma: posterior margin of pronotum forming obtuse angle with anterior margin of mesonotum in profile view; propodeum evenly rounded with dorsal face about as long as posterior face. QUEEN. Measurements (n = 1): TL: 3.19; EL: 0.16; HL: 0.64; HW: 0.61; SL: 0.63; WL: 1.02; GL: 1.53. Indices: BLI: 160; CI: 96; REL: 25; SI: 102. Moderately sized. Color: medium to dark brown, with meso- and metacoxae lighter than mesosoma. Pilosity: most of body covered in moderate to dense pubescence; lacking pubescence on posterior face of propodeum; 1 - 2 small, erect setae on anepisternum.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231545326EFF692C6BFD6DFB53.taxon	materials_examined	Other material examined: MEXICO: Veracruz, Las Cañadas, 19.1906 - 96.99055 ± 60 m, 1390 m, 1. vii. 2016, montane wet forest, baiting, ADMAC # Ba-F- 07 - 1 - 04 - 11; Veracruz, 8 km WSW Xalapa, 19.52177 - 96.99121 ± 20 m, elev. 1500 m, 22. vi. 2016, cloud forest, sifted litter, ADMAC # Wa-F- 05 - 1 - 09; Veracruz, 8 km WSW Xalapa, 19.52165 - 96.99137 ± 20 m, elev. 1510 m, 22. vi. 2016, cloud forest, sifted litter, ADMAC # Wa-F- 05 - 1 - 13; Veracruz, 8 km WSW Xalapa, 19.52181 - 96.9906 ± 20 m, elev. 1500 m, 22. vi. 2016, cloud forest, sifted litter, ADMAC # Wa-F- 05 - 2 - 07; Veracruz, 8 km WSW Xalapa, 19.52275 - 96.99098 ± 20 m, elev. 1500 m, 22. vi. 2016, cloud forest, sifted litter, ADMAC # Wa-F- 05 - 2 - 29; Veracruz, 8 km WSW Xalapa, 19.52283 - 96.99102 ± 20 m, elev. 1500 m, 22. vi. 2016, cloud forest, sifted litter, ADMAC # Wa-F- 05 - 2 - 31; Veracruz, 8 km WSW Xalapa, 19.5236 - 96.99123 ± 20 m, elev. 1500 m, 22. vi. 2016, cloud forest, sifted litter, ADMAC # Wa-F- 05 - 2 - 50.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231545326EFF692C6BFD6DFB53.taxon	etymology	Etymology: The species epithet is derived from ‘ politus ’ (L. = polished), referring to the smooth, shining appearance of the species’ cuticle.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231545326EFF692C6BFD6DFB53.taxon	discussion	Notes: Nylanderia polita workers most strongly resemble those of N. austroccidua and N. contraria but are easily separable from the latter two by their overall smooth cuticle with no microsculpture and complete lack of blue iridescence. Unlike N. austroccidua, this species has an evenly rounded propodeum with the posterior face about as long as the dorsal face in profile view. Unlike N. contraria, the meso- and metacoxae of N. polita are never whitish and at most only somewhat lighter in color than the mesosoma. The known range of this species is limited only to high elevation forests in Veracruz, Mexico (Fig. 2 B).	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231547326AFF692CA2FD45FD95.taxon	description	Figs. 62 – 64 (worker); Figs. 65 – 66 (queen); Figs. 67 – 70 (male)	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231547326AFF692CA2FD45FD95.taxon	materials_examined	Holotype worker, COSTA RICA: San José, 11 km SSE Santa María, 9.55301 - 83.94523 ± 10 m, elev. 1950 m, 24. vi. 2015, cloud forest, sifted litter, ADMAC # Wa-E- 04 - 1 - 49 (USNM: USNMENT 01131798). 5 paratype workers, 1 paratype queen, and 1 paratype male with same locality data as holotype (USNM: USNMENT 01131109, USNMENT 01131799, USNMENT 01131800, USNMENT 01131819, USNMENT 01131831; MNCR: USNMENT 01131802, USNMENT 01131804).	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231547326AFF692CA2FD45FD95.taxon	diagnosis	Worker diagnosis: Antennae relatively short, with scapes surpassing posterior margin by about a quarter to a third of their length; color variable from yellow to dark brown, with meso- and metacoxae at most somewhat lighter than mesosoma; fine cuticular microsculpture resulting in moderate to strong blue iridescence on head, mesosoma, and gaster; moderate to dense cephalic pubescence; propodeum high and evenly rounded, with posterior face steep and at most slightly longer than dorsal face. Compare with: N. mendax, N. mosaica	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231547326AFF692CA2FD45FD95.taxon	description	WORKER. Measurements (n = 11): TL: 2.00 – 2.35; EL: 0.11 – 0.13; EW: 0.08 – 0.10; IOD: 0.32 – 0.39; HE: 0.01 – 0.02; HL: 0.58 – 0.65; HW: 0.47 – 0.53; HLA: 0.18 – 0.23; HLP: 0.27 – 0.30; SL: 0.65 – 0.74; PW: 0.36 – 0.40; MW: 0.18 – 0.21; PrW: 0.26 – 0.32; PDH: 0.18 – 0.27; PTW: 0.13 – 0.15; LHT: 0.58 – 0.69; WL: 0.69 – 0.80; GL: 0.70 – 0.94; SMC: 9 – 12; PMC: 2 – 3; MMC: 2 – 3. Indices: BLI: 144 – 154; CI: 81 – 84; EPI: 67 – 80; HTI: 113 – 131; REL: 18 – 21; SI: 128 – 140. Color: variable, from yellow to dark brown; darker specimens often with yellow to yellow-brown mandibles and leg joints; in darker specimens, meso-and metacoxae somewhat lighter than mesosoma; overall cuticle moderately to finely microsculptured, resulting in moderate to strong blue iridescence on head, mesosoma, and gaster. Pilosity: moderate to dense cephalic pubescence; mesosoma pubescence sparse to absent, limited at most to scattered hairs on pronotum and propodeum, and a fringe of hairs concentrated just posterior to the metanotal groove; gaster pubescence sparse to absent; pair of small, erect setae on apex of petiole. Head: longer than broad and quadrate with distinct posterolateral corners and flattened posterior margin, with moderate medial emargination; scapes surpass posterior margin of head by about a quarter to a third of their length; median ocellus small, but often apparent; lateral ocelli absent or not apparent. Mesosoma: promesonotal area evenly convex in profile view, with posterior margin of pronotum continuous or nearly continuous with anterior margin of mesonotum; propodeum high and evenly rounded, with posterior face steep and at most slightly longer than dorsal face. QUEEN. Measurements (n = 1): TL: 3.73; EL: 0.19; HL: 0.72; HW: 0.69; SL: 0.86; WL: 1.44; GL: 1.58. Indices: BLI: 200; CI: 97; REL: 26; SI: 125. Relatively large. Color: medium to dark brown, with meso- and metacoxae at most somewhat lighter than mesosoma. Pilosity: most of body covered in moderate to dense pubescence; pubescence sparse to absent laterally on pronotum, sparse on most of anepisternum, absent on dorsal half of katepisternum. and absent on posterior face of propodeum; 4 - 5 small, erect setae on anepisternum. MALE. Measurements (n = 1): TL: 2.20; EL: 0.18; HL: 0.53; HW: 0.46; SL: 0.70; WL: 0.82; GL: 0.85. Indices: BLI: 180; CI: 86; REL: 34; SI: 154. Color: medium brown with yellow mandibles; meso- and metacoxae lighter than mesosoma. Pilosity: dense pubescence on head, mesoscutum, and mesoscutellum; pubescence sparse to absent on pronotum, anepisternum, katepisternum, propodeum, and gaster; 1 - 2 small, erect setae on anepisternum. Head: as broad as long; compound eyes surpass lateral margins of head in full-face view; scapes curve sinuously and surpass posterior margin of head by about a third of their length. Mesosoma: In profile view, propodeum gently curved with dorsal face somewhat longer than posterior face. Genitalia: gonopod long, narrow, and evenly triangular to weakly digitiform, with apex tapered and coming to a point (Fig. 71); in ventral view, ventromedial edge of basivolsella unevenly bracket-shaped and crenate, with edge at base of cuspis forming a right angle (Fig. 69); gonossiculus straight and nearly three times longer than cuspis.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231547326AFF692CA2FD45FD95.taxon	materials_examined	Other material examined: COSTA RICA: Heredia, 16 km SSE La Virgen, 10.26667 - 84.08333 ± m, elev. 1100 m, 8. ii. 2001, montane wet forest, leaf litter, ALAS # 11 / B / all; Heredia, 16 km SSE La Virgen, 10.26863 - 84.08287 ± 200 m, elev. 1110 m, 14. iii. 2001, montane wet forest, leaf litter, ALAS # 11 / WF / 02; Heredia, 16 km SSE La Virgen, 10.26863 - 84.08287 ± 200 m, elev. 1110 m, 14. iii. 2001, montane wet forest, leaf litter, ALAS # 15 / WF / 02; Puntarenas, Monteverde, 10.30327 - 84.81099 ± 50 m, elev. 1400 m, 6. i. 2020, moist forest, leaf litter, J. T. Longino # JTL 10993 - s; Puntarenas, Monteverde, 10.30259 - 84.79269 ± 50 m, elev. 1590 m, 13. v. 2014, cloud forest, leaf litter, J. T. Longino # JTL 8625 - s; Puntarenas, Monteverde, 10.28987 - 84.79322 ± 50 m, elev. 1310 m, 13. v. 2014, moist forest, leaf litter, J. T. Longino # JTL 8631 - s; Puntarenas, Monteverde, 10.28744 - 84.79266 ± 50 m, elev. 1180 m, 13. v. 2014, moist forest, leaf litter, J. T. Longino # JTL 8632 - s; Alajuela, 5 km E Monteverde, 10.29824 - 84.78163 ± 50 m, elev. 1495 m, 18. v. 2014, cloud forest, leaf litter, J. T. Longino # JTL 8698 - s; San José, 7.5 km SSE Santa Maria de Dota, 9.58689 - 83.94758 ± 50 m, elev. 1520 m, 27. v. 2014, 2 nd growth cloud forest, leaf litter, T. Sumnicht & J. T. Longino # JTL 8704 - s; San José, 11 km SSE Santa María, 9.55387 - 83.94547 ± 10 m, elev. 1940 m, 24. vi. 2015, cloud forest, leaf litter, ADMAC # Wa-E- 04 - 1 - 21; San José, 11 km SSE Santa María, 9.55378 - 83.94551 ± 10 m, elev. 1940 m, 24. vi. 2015, cloud forest, leaf litter, ADMAC # Wa-E- 04 - 1 - 24; San José, 11 km SSE Santa María, 9.55296 - 83.94551 ± 10 m, elev. 1940 m, 24. vi. 2015, cloud forest, leaf litter, ADMAC # Wa-E- 04 - 1 - 42; San José, 8 km SSE Santa María, 9.58425 - 83.94826 ± 20 m, elev. 1580 m, 23. vi. 2015, cloud forest, leaf litter, ADMAC # Wm-E- 04 - 1 - 02; San José, 8 km SSE Santa María, 9.57877 - 83.95085 ± 20 m, elev. 1620 m, 25. vi. 2015, cloud forest, leaf litter, ADMAC # Wm-E- 04 - 1 - 06; San José, 9 km SSE Santa María, 9.56191 - 83.94807 ± 20 m, elev. 1830 m, 25. vi. 2015, cloud forest, leaf litter, ADMAC # Wm-E- 04 - 1 - 09; San José, 10 km SSE Santa María, 9.55908 - 83.94646 ± 20 m, elev. 1870 m, 25. vi. 2015, cloud forest, leaf litter, ADMAC # Wm-E- 04 - 1 - 10.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231547326AFF692CA2FD45FD95.taxon	etymology	Etymology: The species epithet is derived from Frank Herbert’s science fiction novel Dune. In the novel, “ Usul ” is the secret name given to the protagonist, Paul Atreides, by the Fremen, the desert dwellers of the planet Arrakis. This name references the species’ moderate to intense blue iridescence, alluding to the “ blue-within-blue ” eyes that Paul acquires after joining the Fremen and consuming the spice melange. The term “ Usul ” translates to “ the strength of the base of the pillar ” and is derived from the Arabic word usul, the plural form of asl, which means “ origin, ” “ root, ” or “ principle. ”	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
03EC28231547326AFF692CA2FD45FD95.taxon	discussion	Notes: Nylanderia usul workers most strongly resemble those of N. mendax and N. mosaica. This species is most readily separable from N. mendax by its relatively short scapes, which only surpass the posterior margin of the head by a quarter to a third of their length, whereas in N. mendax they surpass the posterior margin by nearly half their length. There are two distinct color morphs of this species. The dark form is dark brown with yellow to yellow-brown mandibles and tarsi, meso- and metacoxae somewhat lighter than the mesosoma, and has moderate cephalic pubescence, concentrated mostly as patches around the compound eyes (Fig. 4 B). The light form is uniformly yellow, with dense cephalic pubescence (Fig. 4 A). The light form is more likely to be confused with N. mosaica, but the latter is smaller in overall size and bicolored with a yellow to yellow-brown head and mesosoma and medium to dark brown gaster. Interestingly, the light form, represented by NT 002, NT 003, NT 020, and NT 024 in the phylogeny (Fig. 3), resolved as paraphyletic with respect to the dark form. This pattern may indicate a case of incipient speciation, in which one is beginning to diverge from the other but has not yet achieved full reproductive isolation. Consequently, the two forms may be interpretable as two distinct species based on their morphology. However, for now we conservatively treat them all as a single species. If someday these two forms are split into separate species, the dark form will keep the name N. usul and the light form will take a new name. Nylanderia usul is only known from moderate to high elevation forests in Costa Rica (Fig. 2 B), where it is sympatric with only N. mosaica and no other species in American Clade I.	en	Williams, Jason L., Williams, John F., Lapolla, John S., Lucky, Andrea (2025): Nylanderia of the World, Part IV: Taxonomic contributions to the American Clade I of New World Nylanderia (Hymenoptera: Formicidae). Zootaxa 5569 (3): 549-593, DOI: 10.11646/zootaxa.5569.3.10, URL: https://doi.org/10.11646/zootaxa.5569.3.10
