Platystethus crassicornis Motschulsky, 1857

Lü, Liang & Zhou, Hong-Zhang, 2015, Review of the Genus Platystethus Mannerheim (Coleoptera: Staphylinidae: Oxytelinae) in China, Zootaxa 3915 (2), pp. 151-205 : 169-171

4. Platystethus crassicornis Motschulsky, 1857

( Figs. 10 & 11 )

Motschulsky, 1857: 506 (Type locality: Indes orientales); Bernhauer, 1922: 223 ( Formosa); Hammond, 1975: 147, 148, 149 (characters and illustration; Ceylon); Zheng, 1998: 252 ( China); Herman, 2001a: 1479; Smetana, 2004: 518 (subgenus Craetopycrus ); Yan, Li & Zheng, 2012: 342, 343 ( China).

Synonymy.

Platystethus robustus Cameron, 1918: 102 (Type locality: India: Nilgiri Hills); Cameron, 1930: 269 (synonym of crassicornis ).

Platystethus indicus Cameron, 1930: 267 (Type locality: Dehra Dun); Hammond, 1975: 148 (synonym of crassicornis ).

Platystethus (Platystethus) sutteri Scheerpeltz, 1957: 226 , 243 (Type locality: Flores: Moni bei Wolowaru); Hammond, 1975: 148 (synonym of crassicornis ).

Material examined. 17 specimens, 7♂♂, 10♀♀. CHINA: Guangxi: 1♀, Jinxiuxian, Shengtangshan [= Mt. Shengtang, 23.98ºN 110.14ºE], 900–1900 m, 2000. VI.28, J. Yao leg. (IZ-CAS). Hubei: 1♂, Xingshanxian, Longmen river [31.32ºN 110.48ºE], 1994. V.6–7, X.-K. Yang leg. (IZ-CAS). Sichuan: 1♀, Emeishan [= Mt. Emei, 29.52ºN 103.33ºE], from grass heap near ant nest, 2005. VIII.29, Y.-J. Chen leg. (IZ-CAS). Yunnan: 1♂, Chuxiong, Lufengzhen, Guangtong [25.17ºN 101.75ºE], from grass heap in farmland, 2006. VII.28, X.- Y. Li leg. (IZ-CAS). INDIA: 2♂♂, Madura, Chambaganoor, 1912, Donckier leg., Platystethus crassicornis M. det. Bernh., Chicago NHMus M. Bernhauer Collection, Platystethus crassicornis Mots. det. P.M.Hammond 1968 ( FMNH); 1♀, Nilgiri Hills, A. K. Weld Downing leg., Field Mus. Nat. Hist. 1966, A. Bierig Colln. Acc. Z-13812, Platystethus crassicornis Mots. det. P. M. Hammond 1969 ( FMNH); 1♀, S. India, Nilgiris, Field Mus. Nat. Hist. 1966, A. Bierig Colln. Acc. Z-13812, Platystethus crassicornis Mots. det. P. M. Hammond 1969 ( FMNH). INDONESIA: Java: 1♀, Nongkodjadjar, 1911.I, E. Jacobson leg., “ javanus Brh. Typ. Un.”, Chicago NHMus M. Bernhauer Collection, Platystethus crassicornis Mots. det. P. M. Hammond 1968 ( FMNH). Sumatra: 1♀, Fort de Kock, 920 m, 1926, E. Jacobson leg., crassicornis Motsch. det. M. Cameron, don. Jacobson 1928, Chicago NHMus M. Bernhauer Collection, Platystethus crassicornis Mots. det. P. M. Hammond 1968 ( FMNH), Pl. crassicornis Motsch. ( FMNH). MALAYSIA: Borneo, Sabah, Mt. Kinabalu Nat. Pk.: 1♀, HQ at Liwagu River, 1500 m, 1987. V.21, D.E.Bright leg., FIELD MUSEUM ex collection of H. G. Nelson ( FMNH); 1♂, 1♀, Poring Hot Spgs., 495 m, 1988. VIII.23, “[B140]”, A. Smetana leg., FIELD MUSEUM ex collection of H. G. Nelson ( FMNH). NEPAL: 1♀, Nepal-Himalaya, Annapuma Mts., Lamjung Himal, W Taunja Dada, 5 km NO Sikles, 1993. V.19, 2200 –3000 m, J. Schmidt leg. ( HNHM). VIETNAM: 2♂♂, 1♀, Prov. Ha-Tinh, forestière Hüöng-sön, 150 m, forêt trop. pluv., à la lumière [= in light], 1963. VIII.13, T. Pócs leg. ( HNHM).

Redescription. Body shiny and brownish latericeous; maxillary palpi, antennae, and legs lighter; elytra yellowish pale, transparent, with base and apex infuscate. Length [average]: ♂, 4.3 mm; ♀, 4.5 mm.

Male. Head ( Figs. 10 A; 11A) broadest at eyes. Disc less pubescent, with dense and large punctures, surface delicate. Clypeus transverse, surface scarcely punctate, protruding beyond anterior border of supra-antennal ridges, with anterior margin straight or slightly emarginate in middle, furnished a pair of sharp and long (or short in some individuals) spines slightly outcurved at apex. Epistomal suture with middle portion absent, lateral portions fine, short and mesially directed. Supra-antennal ridges elevated. Vertex depressed in anterior part, slightly convex in center; mid-longitudinal suture absent. Eyes ( Fig. 11 E) convex, shorter than temples, with coarse facets; orbital sulcus deep and remarkable around eyes except anterior margin. Temple slightly dilated laterally. Neck constricted, and demarcated by occipital suture, surface delicate in dorsal center but coriaceous in lateral areas. Occipital suture curved, middle portion punctate and discontinuous, lateral portion present, with large setal fovea at each 1/3. Mandible ( Fig. 11 F) stout, sharp, and incurved; bearing 3 teeth on inner edge: front one large, other two fine.

Pronotum ( Figs. 10 A; 11B) narrower than head, widest at anterior 1/4, with mid-longitudinal sulcus deep and wide across whole length, with punctures as dense and large as in head, with micro-striae absent; anterior margin bi-emarginate, anterior lateral angles prominent, posterior angles rounded; lateral margins slightly crenulate, beside each with shallow punctate depression. Scutellum ( Fig. 11 H) with bi-reniform impression. Elytra with posterior margin obliquely truncate, making folded hindwing partly exposed, elytral suture equal with 2/3 elytral length, dehiscent or partly overlapping.

Abdominal sternite VII ( Figs. 10 C; 11I) less haired, situated with two lines of setae, posterior margin shallowly emarginate and in middle with crescent incrassation a little behind. Sternite VIII ( Figs. 10 D; 11J) with two pairs of short and strong setae in center, broadly emarginate in middle of posterior margin; both basal and subbasal ridges continuous in middle.

Aedeagus ( Figs. 10 G–I; 11M–P) with median lobe inflated at base; apical orifice large and fissured to middle of ventral surface, edges of ventral fissure protruding into a pair of long and haired spines with tips rounded; internal sac sclerite-like or membranous, not rolling. Paramere arm-like; basal arm with furrow short and narrow; apical arm triangular at apex, not explanate, furnished with one seta at apex and one longer at near apex of ventral edge, between setae there is reversed triangular process, around ventral side scattered with fine pits.

Female. Head ( Figs. 10 B; 11C) smaller than male yet broader than pronotum; clypeal spines a little shorter. Abdominal sternite VII with posterior margin straight, sternite VIII ( Figs. 10 E; 11K) with posterior margin broadly rounded.

Spermatheca ( Figs. 10 F; 11L) with basal part inflated, with apical part thin and slightly curved. Distribution. China (Guangxi, Hubei, Sichuan, Taiwan, Yunnan); Pakistan, India, Nepal, Myanmar, Borneo, Indonesia, Vietnam.

Figures

FIGURE 10. Platystethus crassicornis Motschulsky, 1857 I: A, head and pronotum ♂ (dorsal view); B, head and pronotum ♀ (dorsal view); C, sternite VII ♂; D, sternite VIII ♂; E, sternite VIII ♀; F, spermatheca; G, aedeagus (ventral view); H, median lobe of aedeagus (lateral view); I, right paramere (in situ) of aedeagus (lateral view). Scales: A, B = 0.5 mm; F = 0.05 mm; rest, 0.3 mm.

FIGURE 11. Platystethus crassicornis Motschulsky, 1857: A, B, head and pronotum ♂ (dorsal view); C, D, head and pronotum ♀ (dorsal view); E, left eye ♂ (showing orbital sulcus); F, right mandible ♂; G, right mandible ♀; H, Scutellum ♂; I, sternite VII ♂; J, sternite VIII ♂; K, sternite VIII ♀; L, spermatheca; M, aedeagus (ventral view); N, aedeagus (dorsal view); O, median lobe of aedeagus (lateral view); P, right paramere (in situ) of aedeagus (lateral view). Scales: K = 0.05 mm; H = 0.1 mm; rest, 0.3 mm.