Coimedon dissimilis ( SHARP , 1874) Assing, 2015

Assing, Volker, 2015, Two new genera of Medonina from China and Japan (Coleoptera: Staphylinidae: Paederinae), Linzer biologische Beiträge 47 (1), pp. 191-206 : 204-205

Coimedon dissimilis ( SHARP, 1874) , nov.comb. ( Figs 30-42 )

Lithocharis dissimilis SHARP, 1874: 66 f.

T y p e m a t e r i a l e x a m i n e d: Holotype 3: " Japan. G. Lewis. 1910-320 / Lithocharis dissimilis . type D.S. / Type H.T. / Holotypus 3 Lithocharis dissimilis Sharp , rev. V. Assing 2015 / Coimedon dissimilis (Sharp) , det. V. Assing 2015 " (BMNH).

C o m m e n t: The original description is based on "One female specimen, found in a rubbish heap at Nagasaki " ( SHARP 1874). An examination of the holotype revealed that it is a male and that it does not belong to Lithocharis .

R e d e s c r i p t i o n: Body length 4.2 mm; length of forebody 2.2 mm. Head, pronotum, and abdomen black; elytra bicoloured, blackish, with the posterior margin broadly yellowish; legs with the femora dark-brown, the tibiae yellowish-brown, and the tarsi yellowish; antennae reddish.

Head ( Fig. 31 ) large in relation to body ( Fig. 30 ) and distinctly transverse, approximately 1.3 times as broad as long, broadest across eyes, with distinctly marked posterior angles, and posteriorly weakly concave; dorsal surface with dense, rather coarse, and granulosely umbilicate punctation ( Fig. 33 ); interstices narrow, but noticeable, and without microsculpture. Ventral aspect of head as in Fig. 32 . Eyes large and bulging, much longer than postocular region in dorsal view ( Fig. 31 ). Antenna 1.05 mm long and shaped as in Fig. 34 .

Pronotum ( Fig. 31 ) strongly transverse, 1.35 times as broad as long and 0.95 times as broad as head, widest at anterior angles; anterior angles sharply marked, posterior angles very indistinct, broadly rounded; lateral margins weakly concave in dorsal view, with two long and stout black setae, one of them at anterior angles and the other a short distance behind anterior angles, these setae inserting in denticle-shaped lateral projections; punctation dense and coarsely granulose ( Fig. 36 ); interstices narrow, but noticeable, and without microsculpture; midline without impunctate band.

Elytra ( Fig. 30 ) approximately 1.3 times as long as pronotum; punctation dense and moderately fine. Hind wings fully developed. All tarsi slender with oblong tarsomeres. Metatarsomere I longer than II, but shorter than the combined length of II and III.

Abdomen narrower than elytra; tergites III-VI and sternites III-VI with distinct anterior impressions; punctation denser and moderately coarse on anterior, sparser and finer on posterior tergites; microsculpture very shallow and composed of scale-shaped meshes; posterior margin of tergite VII with palisade fringe; tergite VIII distinctly oblong and with weakly convex posterior margin.

3: sternite VII with truncate posterior margin and with unmodified pubescence; sternite VIII ( Fig. 42 ) oblong, longer than tergite VIII, and with weakly convex posterior margin, without posterior excision; aedeagus ( Figs 37-38 ) 0.7 mm long, weakly sclerotized, with apically acute ventral process; internal sac with two long series of dark spines and membranous structures.

D i s t r i b u t i o n a n d n a t u r a l h i s t o r y: The type locality is situated in Kyushu, South Japan. According to the original description, the holotype was collected from a "rubbish heap".

Figures

Figs 30-38: Coimedon dissimilis (SHARP): (30) forebody; (31) head and pronotum in dorsal view; (32) head and prothorax in ventral view; (33) median portion of head; (34) antenna; (35) labrum; (36) median portion of pronotum; (37-38) aedeagus in lateral and in ventral view. Scale bars: 30- 32, 34: 0.5 mm; 33, 36-38: 0.2 mm; 35: 0.1 mm.

Figs 39-42: Coimedon dissimilis (SHARP): (39) maxilla; (40) labium; (41) ligula; (42) male sternite VIII. Scale bars: 42: 0.2 mm; 39-40: 0.1 mm; 41: 0.05 mm.