taxonID	type	description	language	source
03DF87F3DE6CFFF4407DFD07FAE5C9CD.taxon	diagnosis	Diagnosis Worker Medial mandibular margin with regularly spaced denticles; ventromedial teeth present or absent. Labrum with multiple rows of peg- or pencil-like chaetae (Griebenow 2024: figs 4 c, 21 a – b). Palp formula 4,1 - 3. Clypeus distinct; epistomal sulcus present. Pair of medial chaetae on second protarsomere. Mesometapleural suture present, scrobiculate. Cuticular microsculpture absent from most sclerites; if present, irregularly reticulate to rugose. Gyne As in worker, but alate. Male Palp formula 4,1 - 3. Ocelli present; not set on tubercle. Notauli present or absent. Pterostigma present. Upper metapleuron distinct from metapectal-propodeal complex; lower metapleuron indistinct from metapectal-propodeal complex. Cupula present, annular (cf. Griebenow et al. 2023: 957, fig. 4 a – c, e) or not (Griebenow et al. 2023: fig. 4 d). Volsellae present; parossiculus and lateropenite distinct. Penial sclerites medially articulated.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE6EFFED4074FA45FD62CFA1.taxon	description	Figs 5 – 10	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE6EFFED4074FA45FD62CFA1.taxon	diagnosis	Diagnosis Worker Cranium dark, conspicuously narrowed anteriorly. Mandible sublinear, with medial peg-like chaetae; dorsal lamella absent; laterodorsal longitudinal groove absent. Outline of clypeus campaniform, surface anteriorly concave; median clypeal ridge not visible. In dorsal view, PrW subequal to propodeal breadth. Mesotibia with one spur. Petiole sessile; anterior corner of dorsal petiolar node rounded in profile view; subpetiolar fenestra present. Abdominal segments II – III without tergotergal and sternosternal fusion; abdominal sternite III convex in profile view. Abdominal segments III – IV narrowly joined; anterior margin of abdominal tergite IV slightly emarginate in dorsal view. Gyne As for worker, but with compound eye. Male Distal 3 maxillary palpomeres subequal in length. Labial palp 2 – 3 - merous. LF 2 ≈ SL. Notauli present, scrobiculate. Hindwing 1 A spectral to absent. Abdominal segment III petiolate. Length of abdominal postsclerites IV> combined length of abdominal postsclerites V – VIII. Cupula annular. Ventral penial process present.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE6EFFED4074FA45FD62CFA1.taxon	materials_examined	Material examined VIETNAM – Ninh Binh • 4 workers; Cuc Phuong National Park; 20.3496 ° N, 105.5957 ° E; 400 m a. s. l.; 8 Aug. 2022; M. G. Branstetter leg.; # 4340; IEBR • 1 gyne; same data as for preceding; IEBR, CASENT 0842884 • 30 larvae; same data as for preceding; IEBR, CSUENT 6000161. – Bac Giang • 2 ♂♂; Tay Yen Tu Nature Reserve; 21.1792 ° N, 106.7228 ° E; 238 m a. s. l.; 30 Mar. 2003; K. Eguchi leg.; in rotten wood; Katsuyuki Eguchi personal collection, CSUENT 6000018, CSUENT 6000019 • 1 worker; same data as for preceding; CSUENT 6000048 • 1 gyne; same data as for preceding; CSUENT 6000047 • 1 worker; Tay Yen Tu Nature Reserve; 21.1697 ° N, 106.7183 ° E; 435 m a. s. l.; 27 May 2004; K. Eguchi leg.; Katsuyuki Eguchi personal collection, CASENT 0179564.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE6EFFED4074FA45FD62CFA1.taxon	description	Measurements and indices Worker (n = 5) HW = 0.46 – 0.49 mm; HL = 0.55 – 0.58 mm; SL = 0.48 – 0.52 mm; ML = 0.28 – 0.39 mm; WL = 0.91 – 0.95 mm; PrW = 0.38 – 0.40 mm; MW = 0.27 – 0.29 mm; PTL = 0.29 – 0.35 mm; PTH = 0.38 – 0.39 mm; PTW = 0.21 – 0.23 mm; PPL = 0.26 – 0.30 mm; PPW = 0.25 – 0.27 mm; PPH = 0.39 – 0.40 mm; CI = 83 – 85; SI = 99 – 110; MI = 60 – 79; PI = 63 – 77; PPI = 86 – 95. Gyne (n = 2) HW = 0.53 – 0.55 mm; HL = 0.63 – 0.64 mm; EL = 0.05 – 0.06 mm; EW = 0.04 mm; SL = 0.53 – 0.56 mm; ML = 0.32 – 0.38 mm; WL = 1.05 – 1.07 mm; PrW = 0.45 – 0.46 mm; MW = 0.32 – 0.33 mm; PTL = 0.32 – 0.36 mm; PTH (n = 1) = 0.45 mm; PTW = 0.27 mm; PPL = 0.28 – 0.30 mm; PPW = 0.30 – 0.35 mm; PPH = 0.46 – 0.47 mm; CI = 84 – 87; SI = 96 – 105 mm; MI = 61 – 69 mm; REL = 8 – 10; OI = 61 – 85; PI = 75 – 84; PPI = 108 – 118. Male (n = 2) HW = 0.64 – 0.65 mm; HL = 0.50 – 0.51 mm; EL = 0.27 – 0.28 mm; EW = 0.20 – 0.21 mm; SL = 0.17 – 0.18 mm; LF 2 = 0.16 mm; MaL = 0.06 mm; WL = 1.06 – 1.11 mm; PrW = 0.56 – 0.57 mm; MSW = 0.51 – 0.58 mm; MSL = 0.54 – 0.55 mm; PTL = 0.22 – 0.23 mm; PTH = 0.20 – 0.22 mm; PTW = 0.18 – 0.19 mm; PPL = 0.22 mm; PPW = 0.24 mm; PPH = 0.25 – 0.27 mm; TW 4 (n = 1) = 0.58 mm; CI = 124 – 132; SI = 27 – 28; MI = 16 – 17; OI = 74 – 75; REL = 53 – 57; MSI = 94 – 95; PI = 79 – 87; PPI = 107 – 113; TI 1 (n = 1) = 46. Description Male Head in full-face view suboval, wider than long (CI = 124 – 132); occiput entire. Mandibles reduced, nublike, edentate, articulated to cranium; mandalus large, occupying most of anterior half of mandibular dorsal surface. Labrum reduced. Palpal formula 4,3. Maxillary palpomeres II – IV elongate, each longer than maxillary palpomere I. Labial palpomeres II – III ~ 0.5 × respective lengths of maxillary palpomeres II – III, respectively. Median clypeal length approximately 1.4 × torular diameter; anterior margin weakly medially concave; posterior margin slightly produced between toruli. Anterior tentorial pit directly anterad antennal torulus in full-face view. Ocellar tubercle absent. Occipital carina present only dorsally. Compound eyes large (REL = 53 – 57), oval; all margins weakly convex. Antenna 13 - merous, filiform; scape cylindrical, SL <EL or EW; pedicel subcylindrical, length a little less than 0.5 × SL; antennomere III nearly as long as scape (LF 2 = 0.16 mm; SL 0.17 – 0.18 mm). In lateral view, anterodorsal face of pronotum depressed at transition to pronotal flange. Mesoscutum strongly convex, slightly longer than height or lateromedian breadth. Antero-admedian signum present. Notauli present, meeting at posterior mesoscutal margin. Parapsidal signa present, weakly impressed, slightly divergent anteriorly. Scutoscutellar sulcus deep and broad. Oblique mesopleural sulcus broad, scrobiculate, bisecting mesopectus. Mesoscutellar height and length subequal, posterodorsal mesoscutellar face convex, not posteriorly produced in lateral view; mesoscutellar disc wider than long; mesoscutellar dorsum high as that of mesoscutum. Metanotum strongly convex in lateral view, with dorsal face narrowly visible in dorsal view. Metapleural gland absent. Propodeum convex in lateral view, without distinct dorsal face; propodeal lobe absent. All legs similar, trochanters sphenoid (i. e., wedge-shaped), femora straight and somewhat anteroposteriorly compressed; proximodistal length of protrochanters ~ 1.5 × as great as width, meso- and metatrochanters ~ 2 × as great as width. Tibial spur formula 1 b, 1 p. Wing membranes hyaline. In forewing, C, Sc + R + Rs, Rf, Mf 1, and 1 A tubular; 2 s-rs + Rs + 4 - 6 spectral; M + Cu spectral; cu-a with weakening adjacent to 1 A. Pterostigma present, large. Hindwing with R + Rs tubular, extending ¼ of distance along costal margin; 1 A spectral, ~ 0.17 × length of R + Rs. Abdominal segments II – III petiolate, with complete tergosternal fusion and distinct tergosternal sutures. Abdominal segment II sessile, longer than wide (PI = 79 – 87), length and height subequal; lateral margins subparallel in dorsal view; abdominal tergite II convex, but petiole without dorsal node; in ventral view, abdominal tergite II subrectangular with rounded margins. Abdominal segment III wider than long (PPI = 107 – 113), 1.12 – 1.24 × as high as long; post-tergite III weakly raised and convex posteriorly; abdominal poststernite III in lateral view with distinct rounded corner, outline of ventral margin sublinear. Abdominal segments IV – VIII without tergosternal fusion. Spiculum present; abdominal sternite IX with robust posteromedian process. Cupula annular, lateromedial breadth slightly greater than maximum anteroposterior length; dorsum anteroposteriorly compressed. Gonopodites articulate. Gonocoxites with complete median fusion, with conspicuous sutures (“ dgcs ” and “ vgcs ” in Fig. 8 C – D); gonocoxital arms fused to form anteromedian apodeme with acute apex, making ventral outline of gonocoxital foramen strongly emarginate in ventral view. Gonostylus a little shorter than gonocoxite, slightly recurved medially in dorsal view. Parossiculus lateromedially compressed, about 0.5 × as long as lateropenite; outline lobate in lateral view, with a few trichoid sensilla on apex. Lateropenite blunt, uncinate in lateral view, apex curved ventrad; ectal surface covered with dense basiconic sensilla; ventromesal margin with conspicuous lateral flange (Fig. 9 E; “ ltpf ”). Penial sclerites without medial fusion, connected via dorsomedial conjunctiva; proximodorsally fused with gonocoxites, but connection weakly sclerotized. Preapical dorsum of penial sclerite bears conspicuous rounded lobes, produced laterad and mesad respectively (Fig. 9 F – G; “ lpl ”, “ mpl ”); lateral lobe lamellate, relatively broad; mesal lobe thicker and narrower. Distodorsal part of penial sclerite smoothly tapering in lateral view, with downcurved apex subacute, ventral denticles absent. Proximoventral part of penial sclerite with long sawlike ventral process (“ vpp ” in Figs 8 D, 9 G) originating distal to lateral penial apodeme, produced ventrad and distad, recurved posterad at ~ 90 ° angle; in lateral view its distoventral and distodorsal margins bear ~ 58 small denticles; distal apex acute. Body dark brownish with paler antenna, mouthparts, and legs. Body sculpture mostly lacking; pronotal flange and anterior of abdominal postsclerites II – III coarsely longitudinally rugose; cinctus of abdominal segment IV scrobiculate. Somal pilosity as in Fig. 6. Gyne As for worker, completely lacking alar sclerites, but somewhat larger (WL = 1.05 – 1.07 mm) and with compound eye (Fig. 5 B). Compound eye anteroposteriorly compressed, small (REL = 10), with 12 ommatidia. Supplementary description Worker As in Xu (2012: 485 – 486), but with the following additions or differences. Labrum with three chaetae. Two rows of mandibular chaetae present, with 12 in dorsal row and 9 in ventral row; ventral row with chaetae expanded distally, except for most proximal chaeta. Subapical mandibular seta present. Palp formula 4,3. Tibial spur formula 1 p, 1 p.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE6EFFED4074FA45FD62CFA1.taxon	distribution	Distribution Further sampling is needed across the putative range of P. gengma to establish the scope of intraspecific variation. The specimens from Cuc Phuong National Park differ from the holotype in having three labral chaetae rather than four, as in the population of P. gengma reported from Mizoram, India (Aswaj et al. 2020). This and other differences between the holotype and the specimens reported here, along with those collected in Mizoram, are of unclear significance for species delimitation. The male of P. gengma closely resembles that of Protanilla TH 03, with the only apparent difference being palpomere count and coloration, with Protanilla TH 03 blackish, whereas P. gengma is browner; this variation may be intraspecific.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE6EFFED4074FA45FD62CFA1.taxon	biology_ecology	Ecology The collections of Protanilla gengma reported here from Tay Yen Tu Nature Preserve are the first from rotten wood, rather than soil or leaf litter (Xu 2012; Aswaj et al. 2020). A pharate worker is here reported within a cocoon from collection # 4340 at Cuc Phuong National Park, marking the first such record for Protanilla (Fig. 10 A). This collection also contained 28 larvae feeding on a juvenile scolopendromorph centipede, consistent with behavior observed in other Leptanillinae. All larvae attached to the centipede were identical in size, therefore appearing to be in the same instar. The co-occurrence of a pharate adult and at least two larval instars would seem to argue against synchronous brood production in P. gengma.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE6EFFED4074FA45FD62CFA1.taxon	discussion	Remarks The contents of Eg 03 - VN- 106 were reported by Eguchi et al. (2014: 23, figs 7 – 8) as Protanilla sp. eg- 1, while CASENT 0179564 was provisionally referred to as Protanilla VN 01 in preceding literature (Borowiec et al. 2019; Griebenow 2020; Griebenow et al. 2022). The 3 - merous labial palp of both worker and male is exceptional among the Leptanillinae, amending the diagnosis for Protanilla and Leptanillinae for both forms. A 2 - merous labial palp is implied to be an apomorphy of the Opamyrmini and Leptanilla. Without reexamination of Protanilla TH 03 we cannot confirm that the assessment of the labial palp as 2 - merous in this male morphospecies (Griebenow 2020: fig. 10 b) was accurate. The description of the first known male belonging to the Protanilla bicolor species-group notably reveals an annular cupula, contrasting with the non-annular cupula of the Protanilla rafflesi species-group (Griebenow et al. 2023) and Opamyrma (Yamada et al. 2020). The annular cupula of Protanilla gengma, and its anterior separation from abdominal sternite VIII – IX and the gonocoxites, is a symplesiomorphy with at least one representative of the Leptanilla thai species-group (Leptanilla zhg-bt 03) and the Leptanilla bethyloides species-group (Griebenow et al. 2023). The ergatogyne here described is the first reproductive female documented for the Protanilla bicolor species-group. Unlike the ergatogynes known in at least one species of the Protanilla rafflesi species-group (Ito et al. 2022), alar sclerites are completely lacking in the ergatogyne of P. gengma. Most Protanilla gynes are alate, indicating that aptery in female reproductives has evolved at least twice in Protanilla, and moreover in different subclades.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE77FFE84097FB91FA88CF8E.taxon	description	urn: lsid: zoobank. org: act: 548 AA 897 - 78 C 9 - 4 D 5 E- 911 B-EBEBA 3721404 Figs 11 – 13 Surface mesh of gyne: https: // sketchfab. com / 3 d-models / casent 0745747 - protanilla-rong-queen- 9 c 0 c 45 b 9 ece 544 bb 96 cba 5518 c 8762 c 1 Surface mesh of worker: https: // sketchfab. com / 3 d-models / casent 0745809 - protanilla-rong-worker- 7349 bc 16 ae 7 d 4520 a 9 f 5395 e 29 c 0 cd 0 f Surface mesh of larva: https: // sketchfab. com / 3 d-models / casent 0745741 - protanilla-rong-larva- 83 ab 874 c 2 fa 8426 ab 1 f 43 d 33872 e 0125	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE77FFE84097FB91FA88CF8E.taxon	diagnosis	Diagnosis Worker Lateral cranial margins converging anteriorly; cranium not bulging towards vertex. Dorsal mandibular articulation visible in full-face view, acute. Clypeal surface planar, posteriorly not elevated above frons; posteromedian margin entire; median clypeal ridge present, visible externally; outline campaniform. Labrum armed with three peg-like chaetae. Mandible linear, without vertical dorsal lamella or laterodorsal longitudinal groove; dorsomedial margin with single row of ~ 12 peg-like chaetae; lateral mandibular face glabrous. Labial palp 1 - merous. Meso- and metatibial spur formula 0,1 p. Petiole sessile, with dorsal node having distinct posterior face; anterior face linear in profile view. In dorsal view, length and breadth of petiolar node subequal. Subpetiolar process present, projecting ventrad the remainder of ventral margin of abdominal sternite II; abdominal sternite II with margin not concave posterad subpetiolar process; fenestra present. Abdominal segments II – III without tergotergal and sternosternal fusion. Dorsal node of abdominal segment III with distinct posterior face, gently sloping. Abdominal segments III – IV not broadly conjoined. Soma concolorous, color yellowish.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE77FFE84097FB91FA88CF8E.taxon	etymology	Etymology From the Vietnamese ‟ r ồng ”, meaning “ dragon ”. The Vietnamese conception of a dragon is tubular and sinuous, with short legs, and often golden coloration. This habitus recalls the Leptanillinae, and particularly the deep yellow color of Protanilla rong sp. nov. The specific epithet is a noun in apposition, and therefore invariant.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE77FFE84097FB91FA88CF8E.taxon	materials_examined	Type material Holotype VIETNAM – Ninh Binh • worker; Cuc Phuong National Park, 350 m NW of park headquarters, 1 – 2 cm within macrotermitine mound; 20.253 ° N, 105.217 ° E ± 200 m; 145 ± 5 m a. s. l.; 10 Aug. 2022; A. Richter leg.; IEBR, CASENT 0842870. Paratypes VIETNAM – Ninh Binh • 7 workers; same data as for holotype; IEBR, CASENT 0842862, CASENT 0842871 to CASENT 0842874, CASENT 0842876, CASENT 0842877 • 1 gyne; same data as for holotype; IEBR, CASENT 0745747. Other material examined VIETNAM – Ninh Binh • 1 larva; same data as for preceding; IEBR, CASENT 0745741.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE77FFE84097FB91FA88CF8E.taxon	description	Measurements and indices Holotype HW = 0.36 mm; HL = 0.47 mm; SL = 0.35 mm; ML = 0.25 mm; WL = 0.66 mm; PrW = 0.27 mm; MW = 0.20 mm; PTL = 0.20 mm; PTH = 0.26 mm; PTW = 0.17 mm; PPL = 0.18 mm; PPW = 0.20 mm; PPH = 0.25; CI = 76; SI = 100; MI = 70; PI = 88; PPI = 112. Paratype workers HW = 0.35 – 0.37 mm; HL = 0.43 – 0.47 mm; SL = 0.34 – 0.37 mm; ML = 0.23 – 0.25 mm; WL = 0.62 – 0.66 mm; PrW = 0.24 – 0.28 mm; MW = 0.19 – 0.20 mm; PTL = 0.17 – 0.20 mm; PTH = 0.24 – 0.27 mm; PTW = 0.16 – 0.19 mm; PPL = 0.17 – 0.18 mm; PPW = 0.19 – 0.20 mm; PPH = 0.24 – 0.26 mm; CI = 76 – 82; SI = 97 – 101; MI = 65 – 70; PI (n = 6) = 82 – 99 mm. Paratype gyne HW = 0.42 mm; HL = 0.50 mm; EL = 0.10 mm; EW = 0.10 mm; SL = 0.38 mm; ML = 0.31 mm; PrW = 0.32 mm; WL = 0.86 mm; MW = 0.29 mm; PTL = 0.19 mm; PTH = 0.33 mm; PTW = 0.22 mm; PPL = 0.20 mm; PPW = 0.24 mm; PPH = 0.32 mm; CI = 78; SI = 98; MI = 79; REL = 20; OI = 100; PI = 118; PPI = 123. Description Worker As for Protanilla wallacei (Griebenow 2024: 91 – 93), but dorsal mandibular articulation acute in full-face view. Posteromedian clypeal margin entire. Anterior of labrum armed with three dentiform, peg-like chaetae. Abdominal sternite II with margin sinuate in profile view, not concave posterad subpetiolar process; subpetiolar process projecting ventrad the remainder of ventral margin of abdominal sternite II; fenestra present, elliptical, not anteroposteriorly compressed, occupying whole of subpetiolar process. Color yellowish. Gyne Head longer than wide (CI = 84); lateral margins moderately convex; occiput emarginate. Compound eyes located slightly behind head midline. Ocelli present. Clypeus as in worker. Labrum visible in full face view; bearing one central, dentiform, peg-like chaeta and a pair of longer, straight setae below it; more distal surface of labrum covered in long, suberect setae, with a short pair of setae centrally. Mandible shape as in workers; mesal margin of mandible with rounded denticles proximally, denticles flattening towards apex; downcurved mandibular apex with three larger denticles; mesal margin proximad mandibular apex with row of 12 dentiform, peg-like chaetae, ventrad denticles; only few long setae inserted below chaetae, longest seta on inner side of apical tooth; outer mandibular surface covered sparsely in setae. Palp formula as in worker; proximal labial palpomere very short, hidden below labrum. Anterior tentorial pit indistinct, laterad and very close to antennal torulus. Postgenal ridge complete. Antenna as in worker. Alar sclerites present, but specimen dealate. Pronotum in dorsal view approximately as long and wide as scutum, with convex sides; outline convex in lateral view. Mesoscutum a rounded trapezoid in dorsal view, slightly convex in profile view. Mesoscutellum in dorsal view <0.5 × mesoscutal length, slightly convex in profile view. Mesopleural area in profile view wide, with narrow meso-metapleural suture. Propodeal width in dorsal view subequal to mesoscutal width, slightly narrowing posteriorly; outline convex in lateral view. Bulla proportionally more elongate than in worker, extending anterad propodeal spiracle. Tibial spurs as in worker. Abdominal segment II about as long as wide in dorsal view (PI = 118); petiolar node anteroposteriorly compressed, with anterior face slightly concave in profile view. Anterior outline of subpetiolar process with backwards bent in distal quarter; posterior outline slightly concave in profile view; process appearing roughly triangular overall. Abdominal segment III proportionally shorter in profile view than in worker (PPI = 123). Coloration as in worker. Vestiture of short, suberect setae present, interspersed with slightly longer erect setae. Larva Instar uncertain. Stenocephalous, with abdominal segment XI widest. Cranium subcircular, almost globular in full-face view, surface smooth and glabrous. Antenna set slightly behind midline of cranium, in full face view as distant from other antenna medially as to lateral margin of cranium, consisting of two flat cone-shaped sensillae in small pits. Mandibles typhlomyrmecoid; ectal surface with a few rounded cuticular processes. Maxilla with two short setae laterally; maxillary palp stout, peg-like, with conical sensillum at apex, two sensillae on ectal surface proximad apex. Galea slightly narrower and longer than palp, with two short, peg-like apical setae. Labrum indistinctly separated from cranium; labral margin with four flat, conical sensilla, and row of minute cuticular projections. Labium with comb of thick microtrichia on a rectangular, shelf-like projection distally, likely representing the glossa; labial palp flat and rounded cone, with distal sensillum. Prothorax ventrally with rows of minute cuticular proceses, such rows sparser on mesothorax and ventral metathorax. Prothoracic process absent. Hemolymph taps absent from abdominal segment IV. Abdominal segments and dorsal thoracic segments covered with dense vestiture of short erect setae; additionally, longer erect setae interspersed, sparse in most of abdominal segments, dense on thorax; many hairs on thorax with short cuticular spines; abdominal terminus covered in long, stout setae.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE77FFE84097FB91FA88CF8E.taxon	distribution	Distribution Known only from the type locality. Putative specimens of this species collected across northern Vietnam at Ben En, Sa Pa, Vu Quang, and Xuan Son National Parks, but not included in this study, must be examined in more detail to confirm their conspecificity.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE77FFE84097FB91FA88CF8E.taxon	biology_ecology	Ecology Respective reproductive biologies of P. wallacei and P. rong sp. nov. differ in that P. rong is presumably monogynous, with alate gynes, whereas P. wallacei is polygynous, with ergatoid gynes. All P. rong larvae in the collected colony are identical in size and therefore in the same instar, suggesting synchronous brood production. Like Leptanilla phthirigyna sp. nov., P. rong was collected in a termite mound (Termitidae: Macrotermitinae), a microhabitat heretofore unobserved for the Leptanillinae, to the best of our knowledge.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE77FFE84097FB91FA88CF8E.taxon	discussion	Remarks Protanilla rong sp. nov. is most similar to Protanilla wallacei, a species endemic to the Sundan region, differing by a more acute dorsal mandibular articulation; subpetiolar process projecting ventrad abdominal sternite III (Fig. 4 A); proportional enlargement of the subpetiolar fenestra (Fig. 4); and yellowish coloration. The gyne of Protanilla rong most closely resembles that of Protanilla lini among Protanilla in which the gyne is known (Hsu et al. 2017), being alate rather than the ergatoid condition observed in P. wallacei (Billen et al. 2013; Ito et al. 2022), but is distinguished from P. lini by smaller size (WL <1.0 mm) and somewhat shorter head (CI <85). Discovery of further gyne specimens in either species may necessitate emendation of this differential diagnosis. Protanilla rong sp. nov. and Protanilla wallacei appear similar, but phylogenomic inference supports (UFBoot = 100; BPP = 1) Protanilla rong as sharing a more recent common ancestor with Protanilla wardi Bharti & Akbar, 2012 (Kerala, India), from which it differs in planarity of the anterior face of the petiolar node and smaller size (WL <0.8 mm); and the aberrant P. jongi (Taiwan), from which its habitus differs far more conspicuously. The heterospecificity of P. jongi with relatives sampled in this study, including P. wallacei, is not in question; by extension, Protanilla rong has verity under our species concept.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE72FFE5407FFB88FAE4C808.taxon	diagnosis	Diagnosis Worker 1 – 4 medial mandibular teeth present. Ventromedial mandibular margin lacking teeth. Peg- or pencil-like chaetae absent from labrum. Dorsal mandibular articulation not visible in full-face view. Palp formula 1 – 2,1. Clypeus indistinct, not extending visibly between antennal toruli. Pair of medial chaetae absent from second protarsomere. Meso-metapleural suture absent; or if present, then unsculptured. Abdominal segments III – IV narrowly joined. Cuticular microsculpture present, scabriculous to areolate. Gyne Compound eyes repressed or present; if present then with 1 – 4 ommatidia. Mandible often falcate, rarely (Leptanilla belantan Griebenow, 2024) with distinct masticatory margin; edentate, or with 1 – 2 subapical teeth. Wings and alar sclerites absent. Abdominal segment III not petiolate. Male Palp formula 1 – 2,1. Ocelli present or absent; if present, then almost always set on tubercle. Notauli absent. Pterostigma absent. Hindwing 1 A absent. Volsellae present or absent; if present, then parossiculus and lateropenite insensibly fused. Cupula present or absent; if present, then annular. Penial sclerites medially fused, rarely (Leptanilla astylina Petersen, 1968; Leptanilla TH 03) articulated.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE7FFFE04048FB0FFD7DCF04.taxon	description	urn: lsid: zoobank. org: act: 8 BBE 61 F 2 - 2 D 95 - 41 EB-B 7 A 0 - 857 E 40222303 Figs 14 – 15 Surface mesh of worker: https: // sketchfab. com / 3 d-models / casent 0745758 - leptanilla-belantanoidesworker- 27 a 618 e 409664 d 6 e 874 cbd 978 d 73 f 163	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE7FFFE04048FB0FFD7DCF04.taxon	diagnosis	Diagnosis Worker Mandible with four teeth, basal tooth truncate; short relative to head. Scape short relative to head. Flagellum submoniliform. Clypeal process present, apex emarginate. Length of subapical tapering seta <½ ML. Maxillary palp 1 - merous. PrW> MW. Pronotal and mesonotal heights of dorsa subequal. Meso-metapleural suture absent. Anterior margin of abdominal segment II linear in dorsal view. Subpetiolar process present, not lamellate. PTL <PPL. Abdominal sternites II – III projecting comparably ventrad craniocaudal axis. PPW <½ TW 4. Length of abdominal postsclerites IV greater than combined length of abdominal postsclerites V – VIII. Male Mandibles inarticulate. Clypeus distinct, extending between toruli; antennal sockets not placed on anterior cranial shelf. LF 2 and ML> SL. Ocelli present, situated on tubercle; anteromedian ocellus directly dorsad compound eyes in profile view. Distal transverse carina absent from procoxa; protrochanter sphenoid; profemur arcuate, arcuate medial carina and apicoventral hook absent; ventromedian carina and cuticular comb absent from protibia. Pronotum and mesoscutum not anteroposteriorly prolonged. Mesoscutellum without posterior process. Forewing M + Cu absent. Metapleuron distinct from metapectal-propodeal complex. Propodeal declivity concave in profile view. Petiole without distinct dorsal node. Abdominal tergite VIII broader than long in posterodorsal view. Mulceators absent. Gonopodites inarticulate, with ventral suture; gonocoxites without dorsomedian fusion; gonostyli present, ventral margins entire and not dorsad ventral gonocoxital margins. Volsellae present, medially separate; apex furcated. Penial sclerites dorsoventrally compressed, medially fused; phallotreme dorso-apical, without setal vestiture.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE7FFFE04048FB0FFD7DCF04.taxon	etymology	Etymology The specific epithet means ‘ like belantan ʼ, referring to Leptanilla belantan, a closely related species. The gender of the specific epithet is neuter.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE7FFFE04048FB0FFD7DCF04.taxon	materials_examined	Type material Holotype VIETNAM – Ninh Binh • worker; Cuc Phuong National Park, 150 m NW of central parking lot; 20.3492 ° N, 105.5970 ° E; 392 m a. s. l.; 8 Aug. 2022; A. Richter leg.; clay soil by rotten log, ~ 2 cm deep; ARVI 0042; IEBR, CSUENT 6000061. Paratypes VIETNAM – Ninh Binh • 4 workers; same data as for holotype; IEBR, CASENT 0842867, CASENT 0842878, CASENT 0842879, CASENT 0842881. Other material examined VIETNAM – Ninh Binh • 2 workers; same data as for preceding; IEBR, CASENT 0842880, CASENT 0842882 • 1 ♂; Cuc Phuong National Park, headquarters; 20.25014 ° N, 105.70469 ° E ± 6 m; 190 m a. s. l.; 7 Aug. 2022; P. S. Ward leg.; PSW 18689 - 01; UCDC, CASENT 0842868 • 1 ♂; same data as for preceding; IEBR, CASENT 0842869 • 1 ♂; Cuc Phuong National Park, headquarters; 20.24790 ° N, 105.70871 ° E ± 4 m; 160 m a. s. l.; 7 Aug. 2022; P. S. Ward leg.; PSW 18688 - 01; P. S. Ward personal collection, CASENT 0883690.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE7FFFE04048FB0FFD7DCF04.taxon	description	Measurements and indices Holotype HW = 0.31 mm; HL = 0.41 mm; SL = 0.25 mm; ML = 0.17 mm; WL = 0.52; PrW = 0.21 mm; MW = 0.15 mm; PTL = 0.12 mm; PTH = 0.11 mm; PTW = 0.10 mm; PPL = 0.10 mm; PPW = 0.10 mm; PPH = 0.14 mm; TW 4 = 0.30 mm; CI = 76; SI = 81; MI = 55; PI = 83; PPI = 100; TI 1 = 33. Workers HW = 0.31 – 0.32 mm; HL = 0.40 – 0.41 mm; SL = 0.24 – 0.26 mm; ML = 0.16 – 0.17 mm; WL = 0.51 – 0.53 mm; PrW = 0.18 – 0.20 mm; MW = 0.13 – 0.15 mm; PTL = 0.11 – 0.13 mm; PTH = 0.11 – 0.12 mm; PTW = 0.08 – 0.10 mm; PPL = 0.09 – 0.10 mm; PPW = 0.09 – 0.10 mm; PPH = 0.14 (n = 4); TW 4 = 0.28 – 0.30 mm; CI = 75 – 79; SI = 75 – 85; MI = 51 – 55; PI = 65 – 93; PPI = 91 – 106; TI 1 = 32 – 36. Male HW = 0.36 mm; HL = 0.23 mm; SL = 0.11 mm; LF 2 = 0.15 mm; MaL = 0.04 mm; ML = 0.06 mm; EW 0.16 mm; EL = 0.13 mm; WL = 0.65 mm; MSW = 0.32 mm; MSL = 0.33 mm; PTL = 0.08 mm; PTH = 0.16 mm; PTW = 0.17 mm; CI = 158; SI = 30; MI = 17; OI = 82; REL = 56; MSI = 98; PI = 206. Description Worker Lateral margins of cranium moderately convex. Occipital carina distinct. Clypeal process present, delimited from cranium by lateral carinae, with posteromedian delimitation from cranium by Λ-shaped signum, projecting well anterior of labrum in full-face view; apex robust, broad in outline, linear, bordered by laminae. Mandible short relative to head; four teeth present; basal tooth large, blunt, not enlarged apically nor distally recurved. Large, tapering basal seta absent from mandible; subapical tapering seta present, only slightly longer than surrounding setae, <½ ML. Maxillary palp 1 - merous. Pedicel length subequal to that of basal flagellomere. Flagellum submoniliform; antennomere 3 subequal in length to distal antennomeres; apical flagellomere> 2 × as long as subapical flagellomere. In dorsal view, pronotal margins strongly convex, pronotal width distinctly greater than mesonotal width (PrW = 0.18 – 0.21 mm; MW = 0.13 – 0.15 mm). Pronotal dorsum slightly convex, elevation equal to that of dorsal mesonotal vertex. Lateral margins of mesonotum and metapectal-propodeal complex subparallel in dorsal view; mesonotum not constricted anteriorly. Meso-metapleural suture absent; fusion of mesonotum with propodeum marked by shallow excavation. Bulla extending anterad propodeal spiracle. Propodeum angular in profile view; propodeal declivity slanted; posterolateral corners rounded. Tarsomeres longer than broad. Meso- and metatibial spur formula 2 b, 2 (1 b, 1 p). Anterior margin of petiole linear in dorsal view. Abdominal segment II longer than wide, with distinct dorsal node; margins parallel in dorsal view; subpetiolar process present, not lamellate, anterior face concave in profile view. Abdominal segment III longer than wide in dorsal view. Breadth of abdominal segment III less than half the breadth of abdominal segment IV in dorsal view. Anteroposterior length of abdominal tergite IV greater than that of V – VIII combined. Mesopectus and ventral surface of petiolar sternite without reticulate sculpture. Coloration castaneous. Male Cranial outline subspherical (CI = 158). Occiput entire. Frons not produced into anterior shelf. Mandible fused to gena; broader than long. Mandalus large, covering entire ectal mandibular surface. Maxillary palp 2 - merous, palpomeres indistinct. Clypeus extending posteriorly between antennal toruli, discernible in full-face view. Anterior tentorial pits situated anterad antennal toruli. Compound eyes wider than long in profile view (OI = 82), large (REL = 56), outline subcircular, all margins entire. Anteromedian ocellus and compound eyes both intersecting line drawn perpendicular to anteroposterior axis of cranium. Scape subcircular in cross-section, longer than wide, SL <EL; pedicel short, vasiform, length 0.5 × SL; antennomere 3 long, cylindrical, length greater than that of scape (SL = 0.11 mm; LF 2 = 0.15 mm); flagellum filiform, extending posterior to mesoscutum if folded flat over mesosoma. Pronotum and mesoscutum not anteroposteriorly prolonged. In profile view anterodorsal pronotal face diagonal to craniocaudal axis at ~ 45 ° angle. Mesoscutal dorsum convex, projecting anteriorly dorsad pronotum; mesoscutum longer than broad. Antero-admedian signum present. Notauli absent. Parapsidal signa present, impressed. Mesoscutellum as tall as long, dorsum higher than that of mesoscutum, posterodorsal mesoscutellar face convex, not posteriorly produced or recurved. Oblique mesopleural sulcus present, not intersecting metapectal-propodeal complex. Metapleuron distinct, juncture between upper and lower metapleuron narrow. Metapleural gland absent. Propodeum concave in profile view, with outline sinuate. Coxal lengths subequal, with procoxal length greatest. Procoxa without distal transverse carina. Protrochanters sphenoid in outline, distally truncate. Profemur slightly curved, with proximal dorsoventral margins converging in lateral view, not anteroposteriorly compressed; acute distal flange on ventral surface absent; arcuate medial carina absent. Protibia slightly shorter than profemur; not dorsoventrally compressed, without ventromedian carina; protibial comb absent; probasitarsal seta smaller than calcar. Spur formula 2 b, 2 b. C and Sc + R + Rs fused, tubular; 2 s-rs + R + 4 - 6, Rsf 1, Mf 1, and M + Cu nebulous; all other venation absent. Costal infuscation absent. Abdominal segment II anteroposteriorly compressed, broader than long in dorsal view (PI = 206), excluding presclerites; dorsal node absent; without median dorsal excavation. Abdominal sternite II without process, convex in profile view. Presclerites of abdominal segments III – VIII inconspicuous. Abdominal segments III – VII without tergosternal fusion. Tergosternal fusion of abdominal segments VIII – IX unknown. Abdominal tergites III – VII anteroposteriorly compressed, lateral margins subparallel or converging; breadth of abdominal tergite VIII subequal to that of abdominal tergite VII in posterodorsal view. Abdominal sternites VIII – IX not visible without dissection. Mulceators absent. Gonopodite inarticulate. Gonocoxites without complete dorsomedian and ventromedian fusion; gonocoxital lamina absent. Gonostylus present, recurved medially, with expansive dorsal laminae; apex entire. Volsella present, transected by articulatory sulcus; bifid, with dorsal process sharply curving laterally, ventral process moderately curving laterally, apex extending distad that of dorsal process. Penial sclerites dorsoventrally compressed, not basally recurved, dorso- and ventromedian carinae absent, lateral margins laminate. Penial apex with deep median incision, phallotreme at proximal extremity of incision. Phallotreme dorsal, apical, not recessed, not surrounded by vestiture of setae. Most sclerites with vestiture of subdecumbent setae; elongated on posterior margins of abdominal tergites VII – VIII; ventral face of volsella distad articulatory sulcus with long, suberect setae; gonostylus with decumbent setae, longer than on soma; genitalia otherwise bare. Cuticle bearing piligerous punctae; sculpture otherwise absent.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE7FFFE04048FB0FFD7DCF04.taxon	distribution	Distribution Known only from Cuc Phuong National Park.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE7FFFE04048FB0FFD7DCF04.taxon	biology_ecology	Ecology Little is definitively known, or can be speculated, regarding the ecology of Leptanilla belantanoides sp. nov. The habitation of this species in soil is unremarkable for Leptanilla.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE7FFFE04048FB0FFD7DCF04.taxon	discussion	Remarks Leptanilla belantanoides sp. nov. appears most similar to L. belantan from peninsular Malaysia and Leptanilla sapa sp. nov., with the shape of the proximal mandibular tooth being intermediate in L. belantanoides between these two species, and its length proportionally shorter than in L. belantan. Emargination of the clypeal process is also less pronounced in the worker caste of L. belantanoides than in either of these relatives. Further sampling of worker members of the Leptanilla thai species-group across mainland southeast Asia, and collection of the corresponding males, will clarify the boundaries between these species. In the male-based key to the Leptanilla thai species-group of Griebenow (2024: 162), Leptanilla belantanoides sp. nov. keys out to the second lug of couplet 9. It is distinguished from Leptanilla zhg-th 05 in that the ventral gonostylar margin is entire, without any projecting angle; and that the ventral gonopodital suture is not coincident with an abrupt ledge. As in Leptanilla zhg-th 05 and several other male morphospecies within the Leptanilla thai species-group, the dorsoventral margins of the male profemur in Leptanilla belantanoides converge proximally, giving the profemur an arcuate outline in profile (Griebenow 2024: fig. 42 A). We predict that the male profemur of Leptanilla belantanoides serves a grasping function in copula. Leptanilla belantanoides sp. nov. is here confirmed to belong to the Leptanilla thai species-group by phylogenomic inference. Beyond L. belantan and Leptanilla sapa sp. nov., among the putative members of the Leptanilla thai species-group for which the worker caste is known, L. belantanoides appears is most closely similar to Leptanilla ujjalai Saroj et al., 2022 and the undescribed Leptanilla zhg-th 02. Males are unknown for these relatives of L. belantanoides, and none have yet been sequenced. All are united in possessing a truncate proximal tooth on the worker mandible, ventrad the masticatory margin. The Leptanilla thai species-group, equivalent to the former genus Yavnella, was originally described from male specimens (Kugler 1987), with the worker caste being heretofore definitively identified only for Leptanilla laventa (Griebenow et al., 2022). The male is unknown in both these species, meaning that L. belantanoides is the first member of the Leptanilla thai species-group for which the worker and male are associated (in this case by UCEs). The male morphospecies that most closely resemble those of L. belantanoides sp. nov. are all undescribed.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE7AFFDC4042FC0DFDCBCB12.taxon	description	urn: lsid: zoobank. org: act: E 28 E 31 C 4 - 959 D- 43 D 4 - BA 12 - 24 E 43 BF 259 AA Figs 16 – 17, 18 Aii Surface mesh of worker: https: // sketchfab. com / 3 d-models / casent 0745756 - leptanilla-sapa-worker-ab 53 16 ce 932 d 4337 a 96 edd 278 ec 52 e 23 Surface mesh of gyne: https: // sketchfab. com / 3 d-models / casent 0745762 - leptanilla-sapa-queen- 28 da 0 ae 5 cc 904 a 47965 eeda 0 cef 2 d 1 e 1	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE7AFFDC4042FC0DFDCBCB12.taxon	diagnosis	Diagnosis Worker As for Leptanilla belantanoides sp. nov., but with the differences stipulated under Description. Gyne Mandible falcate, without distinct basal and masticatory margins, edentate, with two weak blunt denticles. Anterior clypeal margin slightly convex, with median elevation. Compound eye present, with four ommatidia. Meso-metapleural suture laterally present. Abdominal segment II longer than broad, without distinct dorsal node; subpetiolar process absent; rectangular, not constricted anteriorly along anteroposterior or lateromedian axes.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE7AFFDC4042FC0DFDCBCB12.taxon	etymology	Etymology From Sa Pa, the type locality of this species. The specific epithet is a noun in apposition and therefore invariant.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE7AFFDC4042FC0DFDCBCB12.taxon	materials_examined	Type material Holotype VIETNAM – Lao Cai • worker; Hoang Lien National Park, Sa Pa, Mt. Phan Xi Pang, Cong Troi; 1800 – 1900 m a. s. l.; 8 Oct. 2006; K. Eguchi leg.; Eg 08 x 06 - 12; IEBR, CASENT 0745756. Paratypes VIETNAM – Lao Cai • 1 gyne; same data as for holotype; IEBR, CASENT 0745762 • 12 workers; same data as for holotype; IEBR, CSUENT 6000020 to CSUENT 6000031. Other material examined VIETNAM – Lao Cai • 2 workers; Hoang Lien National Park, Sa Pa, Mt Phan Xi Pang, Cong Troi; 2000 – 2200 m a. s. l.; 28 Apr. 2002; K. Eguchi leg.; Eg 02 - VN- 155; IEBR, CSUENT 6000032, CSUENT 6000033 • 3 workers; same locality as for preceding; 28 Apr. 2002; K. Eguchi leg.; Eg 02 - VN- 151; Katsuyuki Eguchi personal collection, CSUENT 6000041 to CSUENT 6000043 • 2 workers; Hoang Lien National Park, Sa Pa, Mt Phan Xi Pang; 22.35121 ° N, 103.77642 ° E; 2000 m a. s. l.; 20 Sep. 2017; K. Eguchi leg.; Eg 24 ix 17 - 378; IEBR, CSUENT 6000034, CSUENT 6000035 • 5 workers; same locality as for preceding; 22.34609 ° N, 103.77459 ° E; 2008 m a. s. l.; 27 Sep. 2017; K. Eguchi leg.; Eg 27 ix 17 - 451; IEBR, CSUENT 6000036 to CSUENT 6000040 • 3 workers; same locality as for preceding; 22.34600 ° N, 103.77469 ° E; 2006 m a. s. l.; 27 Sep. 2017; K. Eguchi leg.; Eg 27 ix 17 - 447; Katsuyuki Eguchi personal collection, CSUENT 6000044 to CSUENT 6000046.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE7AFFDC4042FC0DFDCBCB12.taxon	description	Measurements and indices Holotype HW = 0.36 mm; HL = 0.49 mm; SL = 0.27 mm; ML = 0.25 mm; WL = 0.61 mm; PrW = 0.24 mm; MW = 0.18 mm; PTL = 0.18; PTH = 0.13 mm; PTW = 0.11 mm; PPL = 0.13 mm; PPW = 0.11 mm; PPH = 0.17 mm; TW 4 = 0.35 mm; CI = 74; SI = 74; MI = 68; PI = 59; PPI = 83; TI 1 = 32. Worker paratypes HW = 0.37 – 0.39 mm; HL = 0.48 – 0.54 mm; SL = 0.26 – 0.31 mm; ML = 0.22 – 0.26 mm; WL = 0.62 – 0.71 mm; PrW = 0.25 – 0.28 mm; MW = 0.18 – 0.20 mm; PTL = 0.18 – 0.22 mm; PTH = 0.13 – 0.15 mm; PTW = 0.11 – 0.12 mm; PPL = 0.14 – 0.16 mm; PPW = 0.12 – 0.13 mm; PPH = 0.19 – 0.21 mm; TW 4 = 0.35 – 0.40 mm; CI = 74 – 77; SI = 71 – 77; MI = 60 – 65; PI = 55 – 58; PPI = 76 – 87; TI 1 = 30 – 35. Paratype gyne HW = 0.56 mm; HL = 0.65 mm; ML = 0.41 mm; WL = 1.11 mm; PrW = 0.38 mm; MW = 0.38 mm; PTL = 0.63 mm; PTH = 0.32 mm; PTW = 0.39 mm; CI = 87; SI = 65; MI = 72; PI = 61. Description Worker As in Leptanilla belantanoides sp. nov., but clypeal process posteromedially not clearly delimited from cranium; apex strongly bilobed with distinctly concave anterior margin (Fig. 18 Aii). Proximal mandibular tooth about twice as long as wide, distally slightly recurved. Pronotal dorsum moderately convex, slightly elevated above dorsal mesonotal vertex. Meso-metapleural suture indistinct, faintly furrowed. Bulla reaching propodeal spiracle but not extending anterad. Propodeum rather rounded in profile view; propodeal declivity slanted; posterolateral corners rounded. Tibial spur formula 2 b, 2 (1 b, 1 p). Margins of abdominal segment II subparallel, slightly convex around node in dorsal view. Breadth of abdominal segment III less than half the breadth of abdominal segment IV in dorsal view (TI 1 = 30 – 35). Mesopectus and ventral surface of petiolar sternite with reticulate sculpture. Coloration castaneous. Gyne Labrum deeply emarginate. Cranium in full-face view subrectangular, widest at level of midpoint of genae below eyes; occipital margin linear. Clypeal process absent. Mesonotum laterally delimited from mesopleuron by furrow. In dorsal view, breadth of mesonotum less than that of pronotum or metanotal-propodeal complex. Propodeum with distinct declivity. Abdominal segment II dorsoventrally compressed, subcylindrical, longer than wide, without distinct dorsal node; margins subparallel in dorsal view, weakly converging posteriorly; subpetiolar process absent. In dorsal view, abdominal segment III not conspicuously narrower than abdominal segment IV; axial relative to posterad abdominal segments. Abdominal postsclerites III shorter than postsclerites IV – VII; the latter subequal in length. Vestiture consists of short subdecumbent to suberect setae, longer and more abundant on gaster than on remainder of soma. Coloration pallid.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE7AFFDC4042FC0DFDCBCB12.taxon	distribution	Distribution Known only from the type locality.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE7AFFDC4042FC0DFDCBCB12.taxon	biology_ecology	Ecology Leptanilla sapa sp. nov. is relatively common in the vicinity of Sa Pa, corresponding to Leptanilla sp. eg- 1 reported by Eguchi et al. (2014: 22). The colonies were found under moss layers in a cloud forest (K. Eguchi pers. com.). One colony (Eg 27 ix 17 - 447) contained a paralyzed mecistocephalid centipede (Chilopoda: Geophilomorpha) fed upon by larvae. The upper limit of the elevational range of L. sapa sp. nov. (2200 m) surpasses that reported for any other Leptanilla – only its close relative L. ujjalai and an undescribed male morphospecies of the Leptanilla revelierii species-group (Leptanilla zhg-my 09) approach this, being collected at 2014 m and 1900 m, respectively (Saroj et al. 2022: 6; AntWeb 2024).	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE7AFFDC4042FC0DFDCBCB12.taxon	discussion	Remarks Leptanilla sapa sp. nov. is doubtlessly a close relative of Leptanilla belantanoides sp. nov. and Leptanilla belantan, and therefore belongs to the Leptanilla thai species-group. The worker caste differs from both these species in that the apex of the truncate proximal tooth of the mandible is not at all expanded, nor is this tooth recurved distally; and in that the meso-metapleural suture is distinctly present laterally. Abdominal segment III is proportionally longer in worker L. sapa sp. nov. than in either of these species (PPI = 73 – 88), while abdominal segment II is also proportionally longer in L. sapa than in L. belantanoides (Fig. 18 B). While the phenotype of the worker caste differs little among L. sapa sp. nov. and its close relatives, the gyne of this species diverges conspicuously from that of L. belantan in the presence of compound eyes, with more ommatidia than ever before described in Leptanilla; falcate mandible, without distinct masticatory margin; presence of distinctly impressed meso-metapleural suture; and subrectangular abdominal segment II, lacking the anterior constriction observed in L. belantan along the dorsoventral and lateromedian axes, longer than any of the posterad abdominal segments. This striking differentiation in the gyne corroborates the allospecificity of L. sapa with L. belantan. It remains possible that the phenotypic differences among these three allopatric species in fact represent regional variation in a single geographically widespread species. This could only be falsified by the discovery of two or more of these species in sympatry, while maintaining morphometric distinctness. For the time being, we are confident that Leptanilla sapa sp. nov., Leptanilla belantanoides sp. nov. and L. belantan represent distinct species, since the differentiation in the worker caste among these putative species is qualitatively equivalent to that observed between Leptanilla charonea and Leptanilla zaballosi Barandica et al., 1994, which occur in sympatry and are indubitably allospecific (López et al. 1994; Griebenow 2024). Description of the unknown male of L. sapa will be invaluable for assessing its distinctness from L. belantanoides.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE41FFD8407BFE9BFBB7CB72.taxon	description	urn: lsid: zoobank. org: act: DF 5632 D 4 - B 877 - 481 D-B 991 - 81 FC 1 D 064 A 51 Figs 19 – 20	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE41FFD8407BFE9BFBB7CB72.taxon	diagnosis	Diagnosis Worker Mandible with three teeth, short relative to head. Scape short relative to head. Flagellum submoniliform. Clypeal process absent; clypeal margin linear, entire. Length of subapical tapering seta ~ ½ ML. PrW ≈ MW. Pronotal and mesonotal heights of dorsa subequal. Meso-metapleural suture absent from dorsum. Anterior margin of abdominal segment II linear in dorsal view. Subpetiolar process present, not lamellate. PTL ≈ PPL. Abdominal sternites II – III projecting comparably ventrad craniocaudal axis. PPW ~ ½ TW 4. Length of abdominal postsclerites IV less than combined length of abdominal postsclerites V – VIII. Gyne Mandible falcate, without distinct basal and masticatory margins, subapical tooth present; strongly bowed inward. Anterior clypeal margin slightly convex, without median elevation. Compound eyes absent. Meso-metapleural suture absent. Abdominal segment II as broad as long, with distinct dorsal node; subpetiolar process absent; quadrate, not constricted anteriorly along anteroposterior or lateromedian axes.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE41FFD8407BFE9BFBB7CB72.taxon	etymology	Etymology From the Greek ‘ phthirus ʼ, meaning ‘ louseʼ, and ‘ gyna ʼ, that is, ‘ gyneʼ. This refers to the minute size and dorsoventral compression of the gyne, which along with elongate vestiture on the metasoma grants an ectoparasitic gestalt. Gender of specific epithet is feminine.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE41FFD8407BFE9BFBB7CB72.taxon	materials_examined	Type material Holotype VIETNAM – Ninh Binh • worker; Cuc Phuong National Park; 20.3496 ° N, 105.5957 ° E; 400 m a. s. l.; 8 Aug. 2022; M. G. Branstetter leg.; # 4349; in macrotermitine mound; IEBR, CSUENT 6000054. Paratypes VIETNAM – Ninh Binh • 1 gyne; same data as for holotype; IEBR, CASENT 0842890 • 2 workers; same data as for holotype; IEBR, CASENT 0842891, CASENT 0842892. Other material examined VIETNAM – Ninh Binh • 1 gyne; same data as for holotype; IEBR, CASENT 0842889.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE41FFD8407BFE9BFBB7CB72.taxon	description	Measurements and indices Holotype HW = 0.20 mm; HL = 0.26 mm; SL = 0.13 mm; ML = 0.11 mm; WL = 0.33 mm; PrW = 0.13 mm; MW = 0.11 mm; PTL = 0.08 mm; PTH = 0.09 mm; PTW = 0.07 mm; PPL = 0.07 mm; PPW = 0.09 mm; PPH = 0.10 mm; TW 4 = 0.20 mm; CI = 76; SI = 63; MI = 53; PI = 88; PPI = 125; TI 1 = 43. Paratype workers HW = 0.21 – 0.22 mm; HL = 0.26 – 0.27 mm; SL = 0.13 mm; ML = 0.10 – 0.11 mm; WL = 0.34 – 0.35 mm; PrW = 0.13 – 0.14 mm; MW = 0.12 mm; PTL = 0.09 mm; PTH = 0.09 – 0.10 mm; PTW = 0.08 – 0.09 mm; PPL = 0.08 mm; PPW = 0.09 – 0.10 mm; PPH = 0.11 – 0.12 mm; TW 4 = 0.20 – 0.21 mm; CI = 78 – 81; SI = 60 – 61; MI = 47 – 52; PI = 85 – 99; PPI = 113 – 123; TI 1 = 46 – 48. Paratype gyne HW = 0.28 mm; HL = 0.34 mm; SL = 0.15 mm; WL = 0.59 mm; PrW = 0.20 mm; MW = 0.22 mm; PTL = 0.14 mm; PTH = 0.14 mm; PTW = 0.14 mm; CI = 81; SI = 53; PI = 104. Description Worker Lateral margins of cranium subparallel. Occipital carina only distinct ventrally. Clypeal process absent; clypeal margin linear, entire. Mandibles short relative to head (MI = 47 – 53); three teeth present. Large, tapering basal seta absent from mandible; subapical tapering seta present, no longer than adjacent setae. Maxillary palp 1 - merous. Scape short, less than ½ length of cranium (SI = 60 – 61), somewhat expanded towards apex. Pedicel length distinctly greater than that of basal flagellomere. Flagellum submoniliform; length of antennomere 3 subequal to respective lengths of antennomeres 4 – 6, with lengths of antennomeres 7 – 11 greater than those of antennomeres 4 – 6; antennomere 12 (i. e., apical flagellomere) 2 × as long as antennomere 11. In dorsal view, pronotal margins moderately convex, pronotal width only slightly greater than mesonotal width. Pronotal dorsum planar, not elevated above dorsal mesonotal vertex. Lateral margins of mesonotum and metapectal-propodeal complex subparallel in dorsal view; mesonotum not constricted anteriorly. Meso-metapleural suture absent dorsally; present as signum in profile view. Bulla not extending anterad propodeal spiracle. Propodeum convex in profile view; propodeal declivity indistinct from dorsum; posterolateral corners of propodeum rounded. Tarsomeres longer than broad. Meso- and metatibial spur formula 1 b, 2 b. Anterior margin of abdominal segment II linear in dorsal view. Length of abdominal segment II greater than breadth in dorsal view, distinct dorsal node present; margins parallel in dorsal view; subpetiolar process present, not lamellate, anterior face not concave in profile view. Length of abdominal segment II (PTL = 0.08 – 0.09 mm) subequal to that of abdominal segment III (PPL = 0.08 mm); abdominal sternite III not projecting ventrad abdominal sternite II. Length and breadth of abdominal segment III subequal in dorsal view. Breadth of abdominal segment III approximately half that of abdominal segment IV in dorsal view (TI 1 = 43 – 48). Abdominal tergites IV – VII visible in posterodorsal view. Anteroposterior length of abdominal tergite IV twice anteroposterior length of abdominal tergite V in dorsal view. Abdominal tergite IV not constricted anteriorly. Anteroposterior lengths of abdominal tergites V – VI subequal; anteroposterior length of abdominal tergite VII much less than that of abdominal tergite VI. Sculpture largely absent. Vestiture consisting of short subdecumbent setae, longer and more abundant on gaster than on remainder of soma. Coloration yellowish. Gyne Labrum deeply emarginate. Cranium in full-face view rectangular; occipital margin emarginate. Clypeal process absent. Mesonotum not laterally delimited from mesopleuron by furrow. In dorsal view, breadth of mesonotum greater than that of pronotum or metanotal-propodeal complex. Propodeum without distinct declivity. Abdominal segment II subsessile, abdominal postsclerites II not constricted anteriorly, dorsal apex of petiolar node exceeding dorsal apex of abdominal tergite III; dorsal node situated towards anterior of abdominal segment II. In dorsal view, abdominal segment III conspicuously narrower than abdominal segment IV, supra-axial relative to posterad abdominal segments; lengths of abdominal postsclerites IV and VII subequal, greater than abdominal postsclerites III and V – VI. Vestiture dense, with setae coarse and suberect to subdecumbent on head and mesosoma; setae long, fine, and subdecumbent on metasoma.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE41FFD8407BFE9BFBB7CB72.taxon	distribution	Distribution Known only from the type locality.	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE41FFD8407BFE9BFBB7CB72.taxon	biology_ecology	Ecology Like Protanilla rong sp. nov., L. phthirigyna sp. nov. was collected just below the surface of a termite mound, a microhabitat not previously reported for the Leptanillinae. The discovery of a physogastric gyne (CASENT 0842889) confirms phasic brood production in L. phthirigyna, as in all other Leptanilla for which biology is known. The existence of two gynes in a single putative colony is exceptional for Leptanilla but most be considered only circumstantial without further study: the reproductive phases of these two individuals were not synchronized, contrary to the behavior of gynes in confirmed polygynous ants that practice phasic brood production (e. g., the Cerapachys sulcinodis species-complex [Dorylinae]; Mizuno et al. 2021).	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
03DF87F3DE41FFD8407BFE9BFBB7CB72.taxon	discussion	Remarks The worker of Leptanilla phthirigyna sp. nov. most closely resembles that of Leptanilla okinawensis Terayama, 2013, differing in the proportions of the pedicel, and in that the subpetiolar process is situated midway along the anteroposterior length of abdominal segment II, rather than posterad that point. The condition of the lateral meso-metapleural suture in L. okinawensis is unknown, and this species has not yet been sequenced. Leptanilla phthirigyna sp. nov. is found by phylogenomic inference to belong to the Leptanilla revelierii species-group, corroborated by the absence of a clypeal process and the proportions of abdominal segments IV – VIII. The species belongs to an east Asian radiation of the Leptanilla revelierii species-group that also includes Leptanilla taiwanensis Ogata et al., 1995 (Fig. 2).	en	Griebenow, Zachary Hayes, Richter, Adrian, Economo, Evan P., Dang, An Van, Yamada, Aiki (2025): Four new species of Leptanillinae (Hymenoptera: Formicidae) from northern Vietnam described with phylogenomics and micro-computed tomography. European Journal of Taxonomy 987: 98-145, DOI: 10.5852/ejt.2025.987.2867, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2867/13023
