Stenotarsus rulfoi, 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 : 41-42

Stenotarsus rulfoi sp. nov.

( Figs. 37 , 73 , 109 , 123 , 178 , 234 –235, 266 )

Diagnosis. This species resembles S. spiropenis sp. nov. in the widely truncate terminal labial palpomere ( Figs. 8, 10 ), pronotum with long longitudinal sulci ( Figs. 109, 113 ), elytra with foveolate punctures arranged in longitudinal striae ( Figs. 123, 125 ), mesoventral process with subtriangular figures ( Fig. 138 ), and median lobe twisted or coiled. Stenotarsus rulfoi is distinguished from S. spiropenis by the narrower longitudinal sulci of pronotum ( Fig. 109 ), smaller foveolate punctures on anterior half of elytra (their diameter 2X the diameter of setiferous punctures) ( Fig. 123 ), and the antennae black, with only the scape red.

Description of males. Body 4.66–5.32 mm long, long oval ( Fig. 37 ), moderately convex, 1.91–1.95X as long as wide, 2.90–2.97X as long as high. Uniformly reddish brown, except antennomeres 2–11 which are black. Densely covered with long, suberect, coppery setae.

Head: Clypeus transverse, 2.2X wider than long. Terminal labial palpomere broad, widely truncate apically. Interocular distance 0.68–0.71X as wide as head. Antenna moderately long, markedly stout ( Fig. 73 ), 0.39X as long as body; scape 1.5X as long as wide, 1.8X longer than pedicel; pedicel 0.9X longer than wide; third antennomere 1.1X as long as wide, 1.3X as long as pedicel; fourth as long as wide, 1.2X as long as pedicel; fifth subequal to fourth; sixth as long as wide and as long as pedicel; seventh as long as wide, 1.2X as long as pedicel; eighth 0.9X as long as wide, 1.1X longer than pedicel; antennal club 0.36X as long as total antennal length, with segments almost symmetrical; ninth antennomere widened apically, 0.8X as long as wide, 1.6X as long as pedicel; tenth strongly widened apically, 0.8X as long as wide, 1.6X as long as pedicel; terminal antennomere short subovate, asymmetrical, wider at apical fourth, as long as wide, 2.3X as long as pedicel.

Prothorax: Pronotum widest at base, moderately transverse ( Fig. 109 ), 1.74–1.78X wider than long, 1.81– 1.88X wider at base than at front angles, 2.05–2.15X wider than head. Sides convergent in basal half, then very weakly rounded to front angles. Front angles produced, right-angled to slightly acute, almost sharp at tip. Hind angles briefly acute. Anterior margin narrow, slightly rounded. Lateral margins raised; moderately wide, weakly widening in anterior half and near base; width of margin at base slightly less than 1/4 of the distance between basal pore and hind angle; area between marginal line and pronotal edge flat. Disc finely and closely punctate, weakly convex. Longitudinal sulci long, comparatively deeply and moderately widely excavated, weakly convergent. Basal pores moderately large, slightly curved, markedly oblique. Basal sulcus only impressed very near pores. Pronotal base lobed medially. Prosternal process narrow at base, scarcely widened posteriorly; distinctly narrower than longitudinal procoxal diameter apically.

Pterothorax: Scutellum subpentagonal, rather small, 1.25–1.45X wider than long, 0.12X as wide as pronotum. Elytra 3.15–3.65 mm long, 1.28–1.33X longer than wide, 3.19–3.27X longer and 1.38–1.40X wider than pronotum; rather oblong, widest before basal third, weakly convergent in medial third, than roundly convergent to the rounded apex. Foveolate punctures comparatively small and shallow, arranged in longitudinal rows, lacking in apical half, punctures separated by one diameter ( Fig. 123 ). Humerus prominent. Epipleuron moderately wide at base, 0.85X as wide as the intercoxal process of metaventrite. Mesoventrite scarcely excavated in front; moderately large setose pores laterally; mesoventral process scarcely wider than longitudinal coxal diameter, with three subtriangular figures formed by carinae. Metaventrite moderately convex, without modifications on anterior margin; with pair of moderately large setose pores of approximately same diameter posterior to each mesocoxa. Metepisternum with a moderately large setose pore at anterior margin.

Legs: moderately long and stout ( Fig. 178 ). Trochanters simple. Meso- and metafemora strongly widened at midlength, unarmed; metafemuras long as mesofemur, bearing moderately long decumbent setae. Meso- and metatibiae moderately slender; metatibia as long as metafemur, 0.33–0.35X as long as elytra, continuously widened distally, linear, unarmed. Metatarsus 0.56–0.58X as long as metatibia; second tarsomere produced and lobed, 2.5X as wide apically as fourth tarsomere at midlength.

Abdomen: ventrite I as long as metaventrite and as ventrites II–V combined, with moderately coarse foveolate punctation, without protuberances. Ventrite V twice as long as IV, with apex briefly truncate. Ventrite VI rounded apically. Median lobe very slender, flattened, curved, and slightly twisted, width subequal along its length, in ventral view ( Figs 234–235 ). Tegmen with moderately large submembranous tegminal plate.

Description of females. Body 5.5–5.6 mm long, 1.87–1.93X as long as wide, 2.83–2.92X as long as high. Antenna 0.37X as long as body. Pronotum 1.90X wider than long, 1.89X wider at base than at front angles, 2.09– 2.14X wider than head. Elytra 3.68–3.75 mm long, 1.23–1.30X longer than wide, 3.50–3.52X longer and 1.43– 1.49X wider than pronotum. Metatibia 0.33–0.35X as long as elytra. Metatarsus 0.49–0.52X as long as metatibia. Ovipositor with proctiger rounded, coxites wide, with terminal styli.

Sexual dimorphism. Females have proportionally slightly less elongate antennae and longer, and wider elytra.

Material examined. Types. Holotype (male): México: Jalisco, San Gabriel, El Floripondio, 2300m, BEP, 27.X.1997, ex bajo corteza Pinus, J. L. Navarrete (CZUG); Paratypes: same data as holotype: (1 male, 3 females: CZUG).

Distribution. MEXICO: Jalisco ( Figs. 266 ).

Biological Notes. Altitudinal range: 2300 m. Habitat: oak–pine forest. Period of activity: October. Habit: Collected under bark of Pinus sp.

Etymology. This species is dedicated to the prominent Mexican writer Juan Rulfo, who lived his youth at San Gabriel town, 20 kilometers away from the type locality.

Figures

FIGURES 26 – 37. Habitus in dorsal view of Stenotarsus spp. Scale bar = 1 mm. 26 – 27) S. militaris; 28) S. molgorae; 29) S. monterrosoi; 30) S. nigricans; 31 – 32) S. oblongulus; 33) S. ovalis; 34) S. parallelicornis; 35) S. raramurii: 36) S. rubrocinctus; 37) S. rulfoi.

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 105 – 114. Pronotum of Stenotarsus spp. 105) S. ovalis; 106) S. parallelicornis; 107) S. raramuri; 108) S. rubrocinctus; 109). S. rulfoi; 110) S. sallaei; 111) S. shockleyi; 112) S. smithi; 113) S. spiropenis; 114) S. thoracicus.

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 174 – 185. 174 – 183. Hind legs of male Stenotarsus spp. 184 – 185. Hind legs of female Stenotarsus spp. 174) S. ovalis; 175) S. parallelicornis; 176) S. raramuri; 177) S. rubrocinctus; 178) S. rulfoi; 179) S. sallaei; 180) S. shockleyi; 181) S. smithi; 182) S. spiropenis; 183) S. thoracicus; 184) S. exiguus; 185) S. globosus.

FIGURES 224 – 243. Lateral and ventral view of median lobe of edeagus of Stenotarsus spp. 224 – 225) S. monterrosoi; 226 – 227) S. nigricans; 228 – 229) S. oblongulus; 230 – 231) S. ovalis; 232 – 233) S. parallelicornis; 234 – 235) S. rulfoi; 236 – 237) S. sallaei; 238 – 239) S. smithi; 240 – 241) S. spiropenis; 242 – 243) S. thoracicus.

FIGURES 266 – 267. Distributional maps of Stenotarsus spp. 266) S. oblongulus (C), S. spiropenis (S), S. rulfoi (T); 267) S. sallaei (C). Yellow circles (C), red squares (S), blue triangles (T)

FIGURES 3 – 13. Morphology of Stenotarsus spp. 3) Head; 4) Mandible dorsal; 5) Mandible ventral; 6) Maxilla; 7) Labium; 8) Labial palp; 9) Hind wing; 10) Male abdominal segment IX ventral; 11) Basal fovea of pronotum; 12) Surface of elytron; 13) Metatarsus. 3 – 7, 9 – 13. S. latipes. 8. S. spiropenis.

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.