Stenotarsus cortesi, Arriaga-Varela, Emmanuel, Zaragoza-Caballero, Santiago, Tomaszewska, Wioletta & Navarrete-Heredia, Jose Luis, 2013

Arriaga-Varela, Emmanuel, Zaragoza-Caballero, Santiago, Tomaszewska, Wioletta & Navarrete-Heredia, Jose Luis, 2013, Preliminary review of the genus Stenotarsus Perty (Coleoptera: Endomychidae) from México, Guatemala and Belize, with descriptions of twelve new species, Zootaxa 3645 (1), pp. 1-79 : 11-12

Stenotarsus cortesi sp. nov.

(Figs. 14, 50, 54, 90, 115, 126, 158, 200–201, 245, 257)

Diagnosis. This species is most similar to S. mesoamericanus and S. parallelicornis spp. nov., sharing antennal structure with antennomeres 3–8 as long as wide, and club slightly longer than the rest of antenna with its antennomeres elongate and scarcely widened apically ( Figs. 54, 64 , 72 ). Stenotarsus cortesi is distinguished from these species by pronotum lacking a tooth or angle at midlength of lateral margins ( Fig. 90 ), metatibia distinctly widening apically ( Fig. 158 ), and median lobe strongly widened preapically, in ventral view ( Fig. 201 ).

Description of males. Body 5.85–6.00 mm long, short oval, moderately convex (Fig. 14), 1.65–1.70X as long as wide, 2.7–2.8X as long as high. Uniformly brown except antennal club which is black with apex of terminal antennomere infuscate. Densely covered with long, suberect, coppery setae.

Head: Clypeus transverse, 1.9X wider than long. Terminal labial palpomere narrow, acuminate, narrowly truncate apically. Interocular distance 0.7X as wide as head. Antenna moderately long and distinctly stout ( Fig. 54 ), 0.37–0.39X as long as body; scape as long as wide, 1.7X longer than pedicel; pedicel 0.7X longer than wide; third antennomere 0.9X as long as wide, 1.1X as long as pedicel; fourth 0.9X as long as wide, 1.2X as long as pedicel; fifth to seventh subequal to fourth; eighth 0.7X as long as wide, 1.3X longer than pedicel; antennal club 0.55X as long as total antennal length, with segments almost symmetrical; ninth antennomere scarcely widened apically, 2.9X as long as wide, 3.2X as long as pedicel; tenth scarcely widened apically, 2.3X as long as wide, 3.3X as long as pedicel; terminal antennomere markedly elongate, nearly parallel sided, 2.3X as long as wide, 5.4X as long as pedicel.

Prothorax: Pronotum ( Fig. 90 ) widest at base, transverse, 2.25–2.30X wider than long, 2.25–2.30X wider at base than at front angles, 2.5–2.6X wider than head. Sides continuously rounded to front angles. Front angles produced, right-angled, rounded at tip. Hind angles right-angled. Anterior margin narrow, scarcely arcuate medially. Lateral margins flat to slightly concave, markedly raised, wide; width of margin at base 1/3 distance between basal pore and hind angle; area between marginal line and pronotal edge flat. Disc moderately convex, finely and closely punctate, slightly depressed around longitudinal sulci; longitudinal sulci comparatively deep and long, convergent. Basal pores large, elongate and oblique. Basal sulcus impressed only near pores. Pronotal base lobed medially. Prosternal process narrow at base, widened posteriorly, as wide as longitudinal procoxal diameter apically ( Fig. 126 ).

Pterothorax: Scutellum triangular, small, 1.25X wider than long, 0.14X as wide as pronotum. Elytra length 3.9–4.1 mm; 1.10–1.15X longer than wide; 3.55–3.70X longer and 1.4X wider than pronotum; ovoid, widest near basal third, then roundly converging to the moderately acuminate apex; densely punctate with foveolate punctures large and deep, separated by 2.0–3.5 diameters ( Fig. 115 ), slightly sparser and shallower apically, coarser between humeri and scutellum. Humerus moderately prominent; area between humerus and scutellum depressed. Epipleuron at base 0.85X as wide as intercoxal process of metaventrite. Mesoventrite deeply excavated in front, bearing small setose pores laterally; mesoventral process slightly wider than longitudinal coxal diameter, without medial carinae. Metaventrite markedly convex, without modifications near anterior margin, with pair of small setose pores of approximately same diameter posterior to each mesocoxa. Metepisternum with small setose pore.

Legs: moderately long, rather stout ( Fig. 158 ). Trochanters simple. Meso- and metafemora moderately stout, widest at midlength, unarmed; metafemur slightly longer than mesofemur, bearing moderately long decumbent setae. Meso- and metatibiae moderately stout; metatibia as long as metafemur, 0.33X as long as elytra; strongly widened in apical third, linear, unarmed. Metatarsus 0.56X as long as metatibia; second tarsomere produced and narrow, 1.2X wider apically than fourth tarsomere at midlength.

Abdomen: ventrite I slightly longer than metaventrite and as long as ventrites II–V combined, with moderately large foveolate punctation posterior to metacoxae, without protuberances. Ventrite V almost twice as long as IV, with apex briefly truncate. Ventrite VI rounded apically. Tergite VIII truncate. Aedeagus with median lobe moderately large, curved, narrow, widened before apex, in ventral view ( Fig. 201 ); slightly widened apically, in medial view ( Fig. 200 ). Tegmen with moderately large submembranous tegminal plate.

Description of females. Body 5.9–6.2 mm long, 1.57–1.65X as long as wide, 2.65–2.80X as long as high. Antenna 0.38X as long as body. Pronotum 2.35–2.47X wider than long, 2.34–2.38X wider at base than at front angles, 2.56–2.63X wider than head. Elytra 3.95–4.25 mm long, 1.05–1.13X longer than wide, 3.65–3.90X as long as pronotum, 1.4X wider than pronotum. Metatibia 0.32–0.33X as long as elytra. Metatarsus 0.56X as long as metatibia. Ovipositor with proctiger acuminate, rounded at tip; coxites narrow, without styli ( Fig. 245 ).

Sexual dimorphism. The elytra are slightly longer and broader in females.

Variation. No significant variation was found.

Material examined. Types. Holotype (male): México: Jalisco, Tomatlán, Carretera Talpa-Tomatlán, 7 Km de Macuautitlán, Rancho Potrero Grande, 19° 58´14.55´´ N, 105° 01´30.34´´ W,550 MSNM, BTSC, ex Tronco con hongos, 18 de julio de 2009. J. Cortés-Aguilar y I. Novoa cols. (CZUG); Paratypes: same data as holotype (3 males, 3 females: CZUG; 1 female: CNIN; 1 male: BMNH; 1 female: MNB).

Distribution. MÉXICO: Jalisco ( Fig. 257 ).

Biological Notes. Altitudinal range: 550 m. Habitat: tropical subdeciduous forest. Habits: adults and pupae were found together under a fungusy log ( Fig. 50 ).

Etymology. This species is dedicated to biologist Jesús Cortés-Aguilar, collector of the type series of this species.

Figures

FIGURES 54 – 71. Right antennae of Stenotarsus spp. 54) S. cortesi; 55) S. exiguus; 56) S. globosus, S. rubrocinctus; 57) S. guatemalae; 58) S. incisus; 59) S. kafkai; 60) S. latipes; 61) S. lemniscatus; 62) S. marginalis; 63) S. mesoamericanus; 64) S. mexicanus; 65) S. militaris; 66) S. molgorae; 67) S. monterrosoi; 68) S. nigricans; 69) S. oblongulus; 70) S. ovalis; 71) S. parallelicornis.

FIGURES 72 – 78. Right antennae of Stenotarsus spp. 72) S. raramuri; 73) S. rulfoi; 74) S. sallaei; 75) S. shockleyi; 76) S. smithi; 77) S. spiropenis; 78) S. thoracicus.

FIGURES 90 – 104. Pronotum of Stenotarsus spp. 90) S. cortesi; 91) S. exiguus; 92) S. globosus; 93) S. guatemalae; 94) S. incisus; 95) S. kafkai; 96) S. latipes, S. molgorae; 97) S. lemniscatus; 98) S. marginalis; 99) S. mesoamericanus; 100) S. mexicanus; 101) S. militaris; 102) S. monterrosoi; 103) S. nigricans; 104) S. oblongulus.

FIGURES 158 – 173. Hind legs of male Stenotarsus spp. 158) S. cortesi; 159) S. exiguus; 160) S. globosus; 161) S. guatemalae; 162) S. incisus; 163) S. kafkai; 164) S. latipes; 165) S. lemniscatus; 166) S. marginalis; 167) S. mesoamericanus; 168) S. mexicanus; 169) S. militaris; 170) S. molgorae; 171) S. monterrosoi; 172) S. nigricans; 173) S. oblongulus.

FIGURES 200 – 223. Lateral and ventral view of median lobe of edeagus of Stenotarsus spp. 200 – 201) S. cortesi; 202 – 203) S. exiguus; 204 – 205) S. globosus, S. raramuri, S. rubrocinctus, S. shockleyi; 206 – 207) S. guatemalae; 208 – 209) S. incisus; 210 – 211) S. kafkai, S. mexicanus; 212 – 213) S. latipes; 214 – 215) S. lemniscatus; 216 – 217) S. marginalis; 218 – 219) S. mesoamericanus; 220 – 221) S. militaris; 222 – 223) S. molgorae.

FIGURES 126 – 143. Thoracic structures of Stenotarsus spp. 126 – 133. Prosternal process. 134 – 136. Scutellum. 137 – 138. Mesoventrite. 139 – 140. Metepisternum. 141 – 143. Anterolateral part of metaventrite. 126) S. cortesi; 127) S. globosus, S. rubrocinctus; 128) S. meosamericanus; 129) S. oblongulus; 130) S. ovalis; 131) S. shockleyi; 132) S. spiropenis; 133) S. thoracicus; 134) S. globosus; 135) S. ovalis; 136) S. spiropenis; 137) S. nigricans; 138) S. spiropenis; 139) S. ovalis; 140) S. spiropenis; 141) S. marginalis; 142) S. nigricans; 143) S. spiropenis. PC. Procoxal cavity. PR. Procoxal rest. SP. Setose pore. MC. Mesocoxal cavity.

FIGURES 115 – 125. Surface of elytron of Stenotarsus spp. 115) S. cortesi; 116) S. exiguus; 117) S. globosus; 118) S. kafkai; 119) S. lemniscatus; 120) S. ovalis; 121) S. militaris; 122) S. raramuri; 123) S. rulfoi; 124) S. shockleyi; 125) S. spiropenis.

FIGURES 244 – 256. Female genitalia structures of Stenotarsus spp. 244) Ovipositor with spermatheca and accessory gland of S. spiropenis, dorsal. 245 – 256. terminal part of ovipositor, dorsal. 245) S. cortesi; 246) S. exiguus; 247) S. globosus, S. raramuri, S. rubrocinctus, S. shockleyi; 248) S. incisus; 249) S. latipes; 250) S. mesoamericanus; 251) S. mexicanus; 252) S. monterrosoi; 253. S. nigricans. 254. S. ovalis. 255. S. sallaei. 256. S. thoracicus.

FIGURES 257 – 259. Distributional maps of Stenotarsus spp. 257) S. cortesi (C), S. mesoamericanus (S), S. parallelicornis (T); 258) S. exiguus (C), S. incisus (S); 259) S. globosus (C), S. rubrocinctus (S), S. raramuri. (T). Yellow circles (C), red squares (S), blue triangles.

FIGURES 50 – 53. Habits of Stenotarsus spp. 50) Pupae of S. cortesi sp. nov. on a dead log; 51) A pair of S. latipes Arrow mating on a dead log with Stereum ostrea fungi; 52) S. latipes and S. molgorae sp. nov. feeding on Lactarius sp.; 53) S. spiropenis sp. nov. feeding on Polyporus tenuicollis.