taxonID	type	description	language	source
03ED8780FF97FFFF74A9FCC37FB6FA46.taxon	description	Figs. 1 – 4	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
03ED8780FF97FFFF74A9FCC37FB6FA46.taxon	diagnosis	Diagnosis. Adult male (Figs. 1, 2): body oval and depressed, with widespread vestiture of long and short setae, longer and darker on venter. Head long with a longitudinal furrow on postoccipital region, concave between the eyes; eyes spherical, very prominent; clypeus subtrapezoidal; antennae short, filiform to subserrate, hardly reaching scutellum. Maxillary palpus short, with 4 palpomeres, three basal ones subconical, apical palpomere ovoid. Pronotum trapezoidal, anterior margin arcuate, posterior margin bisinuate and almost as wide as elytral base, lateral margins rounded and unexpanded; with a longitudinal glabrous line and a weak carina on distal half, with a slight depression on each side. Male genitalia: Trilobate, ventrally subrectangular; parameres subtrapezoidal, shorter than middle lobe, with external margin slightly sinuate, ending in a truncate and emarginate apex (Fig. 3); penis in ventral view with expanded rhomboidal shape, with small spines on surface (Fig. 4).	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
03ED8780FF97FFFF74A9FCC37FB6FA46.taxon	materials_examined	Material examined. MEXICO: Chiapas: Marqués de Comillas, Río Lagartos, 16 ° 07 ’ 32.91 ” N, 90 ° 54 ’ 35.42 ” W, 150 m, 10. i. 2017, Barba, López, Benítez, 2 males, D net (CNIN); same data except 30. i. 2019, Barba, 1 male (CNIN). Geographical distribution. BELIZE, Belize, Cayo, Orange Walk, Stann Creek, and Toledo districts. MEXICO, Chiapas, first country record.	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
03ED8780FF97FFF974A9F8AB7B33FE72.taxon	description	Figs. 5 – 8	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
03ED8780FF97FFF974A9F8AB7B33FE72.taxon	diagnosis	Diagnosis. Adult male (Figs. 5, 6): body oval and tapered anteriorly. Head black, short, transversely with very prominent and spherical eyes. Antenna long, filiform subserrate. Maxillary palpus extremely long, second palpomere much longer than other palpomeres. Male genitalia. Trilobate, in dorsal view parameres broad, shorter than middle lobe with external margins sinuate distally, ending in rounded apex with lateral membrane (Fig. 7). In ventral view, penis longer than parameres, digitiform, widening at basal half with robust longitudinal, sublanceolate sclerite (Fig. 8).	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
03ED8780FF97FFF974A9F8AB7B33FE72.taxon	materials_examined	Material examined. MEXICO: Chiapas: Cacahoatán, Ejido El Águila, cascada La Sirena, 15 ° 06 ’ 08.8 ” N, 92 ° 11 ’ 01.3 ” W, 1115 m, 06. xii. 2018, Luna-Luna, Cancino-López, Almaraz-Hernández, Marquez-López, 1 male, D net (CNIN); Cacahoatán, Ejido El Águila, cascada La Sirena, 15 ° 05 ’ 37.0 ” N, 92 ° 10 ’ 46.2 ” W, 1250 m, 24. iii. 2022, Chacón-Hartleven, Chamé-Vázquez, 2 males, Surber sampler (ECO-TAP-E); same data except 21. iv. 2022, 15 males, Surber sampler, 4 males, collected manually (ECO-TAP-E). Geographical distribution. MEXICO, Chiapas (new state record) and Veracruz. Habitat. The specimens from Ejido El Águila were collected from a wadable stream in the sub-basin Alto Cahoá, a tributary of the Cahoacán River, which drains areas with remnants of primary and secondary montane mesophyll forest. Most specimens were collected in riffles with Surber sampler, where water temperature was 18.73 ° C (± 0.34 SD, standard deviation) and dissolved oxygen concentration was 13.41 mg / L (± 0.25 SD). In addition, a few specimens were collected manually on the periphyton of water-covered rocks. High habitat heterogeneity was observed, with an optimal condition of physical habitat (RBP = 0.90), including abundant riparian native vegetation with nearby coffee plantations (shade-grown coffee, Coffea sp.). The stream had turbulent water flow, the elements of the channel were dominated by riffles and rapids zones (60 % of total reach sampled), and composition of the inorganic substrate was dominated by cobbles and boulders (45 % and 35 % of reach sampled, respectively). Also, abundant allochthonous elements (e. g., woody material and leaf packs) were observed in the stream channel.	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
03ED8780FF91FFFB74A9FCE67FFCF9D6.taxon	description	Figs. 9 – 15	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
03ED8780FF91FFFB74A9FCE67FFCF9D6.taxon	diagnosis	Diagnosis. Adult male (Figs. 9 – 15): body oval and depressed; head short, transverse, antennae short, not reaching pronotal base, moniliform; pronotum subtrapezoidal, anterior margin arcuate, posterior margin bisinuate, straight in antescutellar area. Pronotal disc with well-developed, medial, longitudinal carina on distal half. Protibia with a tiny apicolateral denticle and long tarsal lobes. Male genitalia (Figs. 13 – 15): short, wide, subrectangular, trilobate; parameres robust and elongate, close to each other with internal margins fused in dorsal view, apex rounded. Penis digitiform, acuminate apically in dorsal view; apically narrowed, directed ventrally. Psephenops arcei, sp. nov. is close to P. triangularis of Panama by sharing smooth elytra and elongated tarsal lobes (lobe of tarsomere 2 covers ventrally the full-length of tarsomeres 3 - 4 and reaching at least 80 % the length of tarsomere 5). Characters of the genitalia may separate males of both species: in the new species (Figs. 13, 14), parameres in dorsal view are medially close to each other, with margins smooth in ventrolateral view, while in P. triangularis the parameres are medially broadly separate, with an evident tooth on inner margin near the apex. The penis in the new species is digitiform, apically acuminate (Figs. 13, 14), while in P. triangularis it is digitiform, with a basal, lateral, subtriangular projection from each side.	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
03ED8780FF91FFFB74A9FCE67FFCF9D6.taxon	description	Description. Male: body length X ̅ (mean) = 2.7 mm, width X ̅ = 1.5 mm (n = 3). Body oval, depressed; integument yellowish-brown, head black; pronotum dark; elytra yellowish-brown, covered with short yellow setae with golden reflections (Figs. 9, 11); coxae, trochanters, and femora reddish-brown; tibiae and tarsi reddish brown with vestiture short, fine and dense, yellowish-gray (Fig. 10). Head: cypeus subrectangular, declivous at less than 90 degrees from plane of frons, distal margin widely emarginate; fronto-clypeal surface and vertex with long yellowish-brown setae, vertex minutely punctate. Antennae short (i. e., when fully extended backwards, not reaching posterior margin of pronotum), moniliform, with 11 antennomeres; scape longest, pedicel subglobose, half as long as scape; third antennomere subtriangular, pale brown, shorter than pedicel; antennomeres 4 – 10 small, moniliform; apical antennomere acuminate and dark brown (Fig. 9). Eyes lateral, rounded, very prominent, reddish-brown, with dark brown postocular area (Fig. 11). Labrum subrectangular, similar to clypeus but shorter. Maxillary palp with 4 palpomeres, covered with long setae, basal palpomere smallest, apical palpomere longest, with wide sensory area, relative length of palpomeres 0.04, 0.08, 0.06, 0.14; palpomeres 1 – 3 subconical, palpomere 4 acuminate. Labial palp short, with 3 palpomeres, palpomeres 1 – 2 rounded and wide, palpomere 3 subconical, nipple-shaped and slightly longer than preceding ones. Thorax: pronotum width X ̅ = 1.14 mm (n = 3); lateral margin length X ̅ = 0.60 mm (n = 3). Black, subtrapezoidal, basally almost as wide as elytral base; anterior margin arcuate, posterior margin bisinuate, straight in antescutellar area, expanded posterolaterally; posterolateral angles subacute. Pronotal disc with well-developed, dorsomedial, longitudinal carina on distal half, and wide, oval, deep depression at each side of carina (Fig. 9); pronotal surface finely punctate, with minute, yellowish-brown vestiture, and long, dark brown setae. Scutellum short, apex rounded. Elytra with short yellow setae producing golden shining and long yellowish-brown setae; lateral margins parallel on basal three-fourths, then gradually converging posteriorly; humeral width 1.10 mm; surface without striae; length (from base to apex of suture) 1.45 mm; elytral base dark brown. Prosternum dark brown, short; prosternal process lanceolate, deeply grooved longitudinally, apex concave (Fig. 10) reaching anterior half of mesoventrite; mesoventrite shorter than metaventrite, with wide groove receiving prosternal process; metaventrite large and bulky. Legs (Figs. 10, 12): femora robust; tibiae slender, metatibia longer than metafemur, protibia with tiny apicolateral denticle; tarsomeres 1 and 2 ventrally lobed, with thick sponge-like vestiture; ventral lobe of tarsomere 1 extending over basal 0.30 of tarsomere 2; tarsomere 2 the longest, twice as long as tarsomere 1, extending distally and completely covering tarsomeres 3, 4, and basal 0.80 of tarsomere 5; apical claws long, curved, slender, each with small basal tooth. Abdomen: vestiture short, fine, dense, and grayish. Ventrite VI usually hidden under ventrite V; ventrites I and II wide, with posterior margin curved anteriorly in the middle; ventrites III and IV narrow, with posterior margin straight; ventrite V with posterior margin slightly emarginate; ventrite VI short, subtriangular, with posterior margin widely curved posteriorly; ventrite VII or anal plate, oval, subtriangular, narrow, covered with long whitish setae; pygidium oval, partly concealed, emarginate, with long brown setae. Male genitalia: short, wide, subrectangular, trilobate (Figs. 13 – 15); total length 0.60 mm, total width 0.24 mm. Parameres robust and elongate, 0.40 mm long, shorter than penis, uniformly widened, apex rounded; with internal margins fused at basal 0.2 in dorsal view (Fig. 13). Penis length X ̅ = 0.49 mm (n = 3), longer than parameres (Figs. 13 – 15); phallobase concave in dorsal view, bulky-subcylindrical in ventral view, length X ̅ = 0.25 mm, width X ̅ = 0.23 mm (n = 3) (Fig. 13); apical half, subtriangular, lanceolate in ventral view (Fig. 14); apically narrowed, directed ventrally (Fig. 15). Variation. One specimen does not present a dark brown coloration at distal portion of the elytra, body length range was 2.6 – 2.8 mm (n = 3).	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
03ED8780FF91FFFB74A9FCE67FFCF9D6.taxon	materials_examined	Holotype. MEXICO: Chiapas: Ocosingo, Reserva de la Biosfera Montes Azules, Estación de Biología Chajul, Río Lacantún (embarcadero), 16 ° 06 ’ 38.4 ” N, 90 ° 56 ’ 23.6 ” W, 154 m, 12. i. 2017, Barba, 1 male, D net (CNIN). Paratypes. MEXICO: Chiapas: Marqués de Comillas, río Ixcán (embarcadero), Rta. 307 Palenque-La Trinitaria, 16 ° 05 ’ 22.43 ” N, 91 ° 05 ’ 19.42 ” W, 150 m, 22. ii. 2016, Barba, Mayorga, 1 male (CNIN); Marqués de Comillas, río Ixcán (embarcadero), Rta. 307 Palenque-La Trinitaria, 16 ° 05 ’ 34.45 ” N, 91 ° 05 ’ 30.11 ” W, 166 m, 8. i. 2017, Barba, 1 male (CNIN). Geographical distribution. MEXICO, Chiapas, Ocosingo and Marqués de Comillas municipalities.	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
03ED8780FF91FFFB74A9FCE67FFCF9D6.taxon	etymology	Etymology. This species is named after entomologist Roberto Arce-Pérez, for his contribution to the taxonomy of aquatic Coleoptera of Mexico, including Psephenidae. Habitat. Specimens were collected in the riparian zones of large, unwadable rivers. The holotype was collected in the Lacantún River, a tributary of Usumacinta river, draining remnants of tropical rainforest, and characterized by a highly turbulent water flow, with channel elements dominated by fast-flowing habitats (e. g., rapids and riffles), and inorganic substrate dominated by cobbles. Specimens from Marqués de Comillas (paratypes) were collected at Ixcán River, from the sub-basin Lacantún River. The river had scarce riparian vegetation and a highly turbulent water flow, with channel elements dominated by fast-flowing habitats (e. g., rapids and riffles) and inorganic substrate dominated by pebbles.	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
03ED8780FF93FFFA74A9F9337AADFB97.taxon	description	Figs. 16 – 19	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
03ED8780FF93FFFA74A9F9337AADFB97.taxon	diagnosis	Diagnosis. Adult male (Figs. 16, 17): body oval and depressed, head short, transverse, antenna long and moniliform; pronotum subtrapezoidal, anterior margin arcuate, posterior margin bisinuate as wide as elytral base, lateral margins straight along anterior half and expanded laterally on posterior half. Pronotal disc with median longitudinal carina well developed on distal half. Protibia with a denticle and tarsal lobes short. Male genitalia (Figs. 18, 19): short, wide, subrectangular, trilobate with parameres subparallel in apical third, medial margin of each paramere separated by wide U-shaped cleft, with tips of parameres not truncate and not divergent, basal half of parameres fused, ventral sclerite of penis subtriangular with apex bifid.	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
03ED8780FF93FFFA74A9F9337AADFB97.taxon	materials_examined	Material examined. MEXICO: Chiapas: Pichucalco, Tectuapan, 17 ° 28 ’ 58.0 ” N, 93 ° 06 ’ 53.0 ” W, 46 m, [?]. v. 2017, Castillo-Uzcanga, Espinoza-Toledo, 2 males, Surber sampler (ECO-TAP-E); Pichucalco, sitio experimental de INIFAP, 17 ° 33 ’ 30.9 ” N, 93 ° 03 ’ 26.2 ” W, 54 m, 29. v. 24, Chacón-Hartleven, 2 males (ECO-TAP-E); Ixtacomitán (17 ° 25 ’ 39.93 ” N, 93 ° 05 ’ 34.98 ” W), 193 m, 30. v. 2024, 1 male (ECO-TAP-E); Veracruz: Los Tuxtlas, 18. vi. 1985, Muñoz, 1 male (CNIN); same data except 18. v. 2015, Contreras-Ramos, 1 male, D net (CNIN); Los Tuxtlas, Río Máquinas, 18 ° 37 ’ 16.0 ” N, 95 ° 05 ’ 26.6 ” W, 21 m, 29. iv. 2016, Contreras-Ramos, 9 males, D net (CNIN). Geographical distribution. BELIZE, Cayo and Toledo districts; MEXICO, Chiapas and Veracruz states - first records for the country. Habitat. Specimens from Tectuapan, Chiapas, were collected in fast-flowing zones of wadable streams in the Pichucalco River sub-basin, a tributary of the Grijalva River. Two specimens were collected in rapids of a stream that drains areas of cultivated pasture, where water temperature was 27.16 ° C (± 2.14 SD) and dissolved oxygen concentration was 8.31 mg / L (± 1.04 SD). The stream had a good physical habitat condition (RBP = 0.67), with channel elements dominated by habitats with fast-flowing water, specifically rapid zones (40 % of reach sampled) and inorganic substrates dominated by cobble and gravel (40 % and 35 % of reach sampled, respectively) (Espinoza-Toledo 2018). Two specimens were collected in riffles of a stream that drains areas of pristine primary forest with abundant riparian vegetation, where water temperature was 28.65 ° C (± 0.35 SD) and dissolved oxygen concentration was 6.61 mg / L (± 0.29 SD). This stream had an excellent quality of physical habitat (RPB = 0.95), with channel elements dominated by riffle and rapids zones (> 65 % of reach sampled) and inorganic substrates dominated by cobbles (70 % of reach sampled). The specimen from Ixtacomitán, Chiapas, was collected in riffles of a stream from the Pichucalco River sub-basin, a tributary of the Grijalva River, running through human settlements. The stream presented a moderate physical habitat condition (RBP = 0.60), with direct wastewater discharge into the channel and abundant inorganic and organic waste materials; despite abundant riparian vegetation, anthropic contamination and alterations are evident. Channel elements were dominated by rapids (50 % of reach sampled), where water temperature was 26.71 ° C (± 0.23 SD), dissolved oxygen concentration was 7.13 mg / L (± 0.34 SD), and inorganic substrates were dominated by pebbles and sand (50 % and 30 % of reach sampled, respectively).	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
03ED8780FF92FFF774A9FA267DF3FDE6.taxon	description	Figs. 20 – 23	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
03ED8780FF92FFF774A9FA267DF3FDE6.taxon	diagnosis	Diagnosis. Adult male (Figs. 20, 21): body oblong-ovate, rather broad, depressed, dorsum shining, densely pubescent. Head profusely rugulose, vertex foveate, dorsal concavity not divided. Elytra oblong, little wider than thorax; pronotal sides strongly convergent anteriorly, apex not more than half as wide as base. Maxillary palp threequarters length of antenna, second segment of maxillary palp usually longer than third and fourth combined. Male genitalia (Figs. 22, 23): apex of median penial spicule enlarged and bluntly rounded.	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
03ED8780FF92FFF774A9FA267DF3FDE6.taxon	materials_examined	Material examined. MEXICO: Chiapas: Cacahoatán, Ejido Ahuacatlán (15 ° 02 ’ 20.4 ” N, 92 ° 10 ’ 15.6 ” W), 680 m, 22. iii. 22, Chacón-Hartleven, Chamé-Vázquez, 1 male, D net (ECO-TAP-E); Pichucalco, Tectuapan, 17 ° 28 ’ 47.74 ” N, 93 ° 07 ’ 21.32 ” W, 66 m, 8. iii. 2024, Chacón-Hartleven, 3 males, Surber sampler (ECO-TAP- E); same data except 01. iv. 2024, 1 male (ECO-TAP-E); same data except 30. iv. 2024, 2 males (ECO-TAP-E); Pichucalco, Tectuapan, 17 ° 26 ’ 13.30 ” N, 93 ° 09 ’ 31.76 ” W, 99 m, 29. iv. 2024, 2 males (ECO-TAP-E); Pichucalco, sitio experimental del INIFAP, 17 ° 33 ’ 30.9 ” N, 93 ° 03 ’ 26.2 ” W, 54 m, 29. v. 24, 1 male (ECO-TAP-E); Guerrero: Cacahuamilpa, Río Dos Bocas, 1. iv. 1984, Vázquez, Villa, 1 male (CNIN); R [uta] 1 [3] 4 Altamirano-Zihuatanejo Km 102, 22 - vi- 1990, 1300 m, Bueno, Barrera, 1 male (CNIN); Morelos: Amacuzac, Río Chalma (ojo de agua), 25. iii. 1984, Vázquez, 1 male (CNIN); Tlaltizapán, Balneario Ejidal Sta. Isabel, 150 m, 16. iv. 1997, Bueno, Barba, Rojas, González, 1 male (CNIN); Oaxaca, Teotitlán, Río Xiquila, 5. v. 1988, Cervantes, 2 males (CNIN); San Juan Bautista Cuicatlán, (Santiago) Dominguillo, río Las Huertas, 12. vi. 1996, Barba, Rojas, 1 male (CNIN); Puebla: Telpatlán, 3. x. 1988, Cervantes, 1 male (CNIN); Tabasco: Huimanguillo, Villa G [uadalu] pe 2 da. Secc., arroyo Las Flores, Carr [etera] Malpasito-Carlos A. Madrazo 5.92 km, 17 ° 22 ’ 30.0 ” N 93 ° 36 ’ 15.0 ” W, 12. vi. 1997, Bueno, Barba, 1 male (CNIN); Veracruz: Los Tuxtlas, Río Máquinas, 14. vii. 1979, Bueno, 1 male (CNIN); Los Tuxtlas, Balzapote, 5. v. 1981, Hernández, Ortega, 2 males (CNIN), Santiago, 1 male (CNIN); same data except 14. v. 1984, Rodríguez, 2 males (CNIN); Los Tuxtlas, río La Palma, 18. vi. 1996, Alatorre-Castillo, 1 male (CNIN); Los Tuxtlas, río Máquinas, 18 ° 37 ’ 16 ” N, 95 ° 05 ’ 26.6 ” W, 21 m, 29. iv. 2016, Contreras-Ramos, 2 males, D-net (CNIN). Geographical distribution. MEXICO, Chiapas (new state record), Estado de México, Guerrero (new state record), Hidalgo, Morelos, Oaxaca (new state record), Puebla (new state record), Tabasco (new state record), and Veracruz (new state record) (Fig. 25). Habitat. The specimen from Ahuacatlán, Chiapas was collected from emergent macrophytes at the riparian zone of a wadable stream of the sub-basin Bajo Cahuá, a tributary of the Cahoacán River. The stream drains agricultural areas, with sun coffee plantations (Coffea sp.) and exotic eucalypt trees (Eucalyptus sp.) along the riparian zone. The specimen came from riffles, where water temperature was 21.93 ° C (± 0.63 SD) and the dissolved oxygen concentration was 13.68 mg / L (± 0.78 SD). The stream had a good physical habitat condition (RBP = 0.66) with turbulent water flow, channel elements were dominated by riffles and rapids (60 % of reach sampled), and inorganic substrate was dominated by pebbles and gravel (35 % and 30 % of reach sampled, respectively). The specimens from Tectuapan, Chiapas were collected in fast-flowing zones of wadable streams of the Pichucalco River sub-basin, tributaries of the Grijalva River. Six specimens came from riffles of a stream that drains areas with mixed land uses, including primary-secondary forests and cultivated pastures, where water temperature was 28.68 ° C (± 3.75 SD) and dissolved oxygen concentration was 4.55 mg / L (± 0.27 SD). Two specimens were found in riffles of a stream that drains areas of secondary forest, where water temperature was 30.42 ° C (± 0.62 SD) and dissolved oxygen concentration was 7.05 mg / L (± 0.51 SD). One specimen was found in riffles of a stream that drains areas of primary forest with abundant riparian vegetation and pristine conditions, where the water temperature was 28.65 ° C (± 0.35 SD) and dissolved oxygen concentration was 6.61 mg / L (± 0.29 SD). The stream had a physical habitat condition ranging from good to excellent (RBP = 0.70, 0.75 and 0.95, respectively), channel elements were dominated by riffles and rapids (50 - 60 % of reach sampled), and inorganic substrates were dominated by pebbles (50 % and 60 % of reach sampled) and cobbles (70 % of reach sampled), respectively.	en	Chacón-Hartleven, Erick A., Luna-Luna, Alba Magali, Chamé-Vázquez, Eduardo R., Mejía-González, Gamaliel, Contreras-Ramos, Atilano (2025): A new species of Psephenops Grouvelle, 1898, with new distribution data and habitat notes of the psephenine water-penny beetles from Mexico (Coleoptera: Psephenidae: Psepheninae). Zootaxa 5722 (1): 79-94, DOI: 10.11646/zootaxa.5722.1.3, URL: https://doi.org/10.11646/zootaxa.5722.1.3
