Stenotarsus smithi Gorham

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 : 45-46

Stenotarsus smithi Gorham

( Figs. 40 , 76 , 112 , 181 , 238 –239, 264 )

Stenotarsus smithi Gorham, 1890: 140 . Blackwelder 1945: 440; Strohecker 1953: 56; Arriaga-Varela et al. 2007: 16; Shockley et al. 2009a: 85.

Diagnosis. This species resembles S. monterrosoi sp. nov. by its small size (less than 4.0 mm) and body uniformly brown ( Figs. 29 , 40 ). It can be distinguished by the smaller body (3.0 mm), longer antennae (0.4X as long as body) ( Fig. 76 ), the second tarsomere distinctly widened apically and different shape of median lobe ( Figs. 238–239 ).

Description of male. Body 3.0 mm long, short oval ( Fig. 40 ), markedly convex; 1.7X as long as wide; 2.6X as long as high. Uniformly dark brown except last four antennomeres which are black. Densely covered with long, suberect, golden setae.

Head: Clypeus slightly transverse 1.6X wider than long. Terminal labial palpomere narrow, acuminate, narrowly truncate apically. Interocular distance 0.7X as wide as head. Antenna moderately long and slender ( Fig. 76 ), 0.4X as long as body; scape 1.4X as long as wide, 1.4X longer than pedicel; pedicel 1.4X longer than wide; third antennomere 1.7X as long as wide, 1.2X as long as pedicel; fourth 1.5X as long as wide, as long as pedicel; fifth to seventh subequal to fourth; eighth 1.2X as long as wide, as long as pedicel; antennal club 0.4X as long as total antennal length, with segments almost symmetrical; ninth antennomere widened apically, 1.1X as long as wide, 1.6X as long as pedicel; tenth strongly widened apically, 0.8X as long as wide, 1.5X as long as pedicel; terminal antennomere ovoid, widest about midlength, 1.3X as long as wide, 2.9X as long as pedicel.

Prothorax: Pronotum widest at base; transverse ( Fig. 112 ); 2.08X wider than long; 2.32X wider than head; 2.0X wider at base than at front angles. Sides rounded to front angles. Front angles slightly produced, right-angled, rounded at tip. Hind angles right-angled. Anterior margin narrow, very scarcely arcuate medially. Lateral margins raised, wide, weakly narrowing near base: width of margin at base 1/3 of the distance between basal pore and hind angle; area between marginal line and pronotal edge flat. Disc moderately convex, finely and closely punctate. Longitudinal sulci rather feeble, short, weakly curved. Basal pores small, slightly elongate, weakly oblique. Basal sulcus only impressed near pores. Pronotal base weakly lobed medially, nearly straight near scutellum. Prosternal processnarrow at base, widened posteriorly; as wide as longitudinal procoxal diameter apically.

Pterothorax: Scutellum triangular, small, 1.5X wider than long, 0.12X as wide as pronotum. Elytra length 1.95 mm; 1.06X longer than wide; 2.85X longer and 1.28X wider than pronotum; ovoid, widest near basal third, then roundly converging to the weakly acuminate apex; moderately densely punctate with foveolate punctures moderately large and deep, separated by 2–4 diameters, sparser and larger at sides. Humerus weakly prominent. Epipleuron at base 0.8X as wide as intercoxal process metaventrite. Mesoventrite deeply excavated in front; setose pores small; mesoventral process as wide as longitudinal coxal diameter, without medial carinae. Metaventrite moderately convex, without modifications near the anterior margin; with a pair of small setose pores of approximately same diameter posterior to each mesocoxa. Metepisternum with small setose pore.

Legs: rather short and slender ( Fig. 181 ). Trochanters simple. Meso- and metafemora rather slender, scarcely widest before midlength; Meso- and metafemora unarmed; metafemuras long as mesofemur, bearing moderately long decumbent setae. Meso- and metatibiae very slender; metatibia scarcely shorter than metafemur, 0.36X as lons as than elytra; very weakly and gradually widened apically, linear, medial margin unarmed. Metatarsus 0.57X as long as metatibia; second tarsomere produced and widened, 2.0X as wide apically as fourth tarsomere at midlength.

Abdomen: ventrite I as long as metaventrite and ventrites II–V combined, with sparse large foveolate punctation, without protuberances. Ventrite V twice as long as IV, with apex rounded. Ventrite VI rounded apically. Tergite VIII moderately truncate posteriorly. Median lobe small, curved, moderately narrow, widened near apical 2/ 3 in ventral view ( Fig. 239 ); almost of same width in lateral view ( Fig. 238 ).

Description of female. Unknown.

Sexual dimorphism. Unknown.

Variation. Unknown.

Material examined. Type. Holotype (male): Holotype [round, red bordered label] / Type [round, red bordered label] / Teapa, Tabasco, Feb, H.H.S. / Sp. figured / B.C.A., VII, Stenotarsus [p] smithi Gorh. [h] (NHM).

Distribution. MEXICO: Tabasco ( Fig. 264 ).

Figures

FIGURES 38 – 42. Habitus in dorsal view of Stenotarsus spp. Scale bar = 1 mm .. 38) S. sallaei; 39) S. shockleyi; 40) S. smithi; 41) S. spiropenis: 42) S. thoracicus.

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 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 263 – 265. Distributional maps of Stenotarsus spp. 263) S. lemniscatus (C), S. monterrosoi (S); 264) S. militaris (C), S. smithi (S); 265) S. ovalis (C), S. molgorae (S), S. thoracicus (T). Yellow circles (C), red squares (S), blue triangles (T).

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.