Gnathymenus multiplicus, Assing, 2015

Assing, Volker, 2015, New species and additional records of Dolicaonina from Ecuador (Coleoptera: Staphylinidae: Paederinae), Linzer biologische Beiträge 47 (2), pp. 1119-1132 : 1129-1130

Gnathymenus multiplicus nov.sp. ( Figs 32-37 )

T y p e m a t e r i a l: Holotype 3: " Ecuador - Esmeraldas, San Francisco , 1°06.5'N, 78°41.7'W, 11.XI.2013, Brachat / Holotypus 3 Gnathymenus multiplicus sp. n. det. V. Assing 2015" (cAss).

E t y m o l o g y: The specific epithet (Latin, adjective: ramified, intricate) alludes to the shape of the aedeagus.

D e s c r i p t i o n: Very small species; body length 2.4 mm; length of forebody 1.2 mm. Coloration: body bicoloured; body pale-reddish with the posterior third of the elytra and the posterior half of abdominal segment VII infuscate; legs, antennae, and maxillary palpi yellowish.

Head ( Fig. 32 ) 1.05 times as broad as long, widest across eyes, lateral margins behind eyes subparallel; dorsal surface with very sparse punctation, median dorsal portion nearly impunctate; interstices without microsculpture. Eyes rather small, approximately as long as postocular region in dorsal view. Antenna approximately 0.5 mm long.

Pronotum ( Fig. 32 ) 1.08 times as long as broad and 1.04 times as broad as head, widest in anterior half and distinctly tapering posteriad; midline broadly impunctate, laterally not delimited by distinct series of punctures; lateral portions with conspicuously sparse punctation; interstices without microsculpture.

Elytra ( Fig. 32 ) moderately long, 0.9 times as long as pronotum and with marked humeral angles; punctation fine and sparse; interstices without distinct microsculpture. Hind wings not examined. Metatarsomere I longer than II.

Abdomen slightly narrower than elytra; segments III-VI with distinct paratergites; punctation moderately fine and moderately sparse; interstices with shallow microsculpture composed of transverse meshes; posterior margin of tergite VII with palisade fringe; posterior margin of tergite VIII strongly convex.

3: sternites III-V unmodified; sternite VI with shallow median impression; sternite VII ( Fig. 33 ) strongly transverse, in the middle with a pair of oblong clusters of long dark setae, posterior margin weakly concave; sternite VIII ( Fig. 34 ) weakly transverse and with conspicuously deep median incision, this incision nearly reaching anterior margin of sternite; aedeagus ( Figs 35-37 ) strongly asymmetric and slender, 0.45 mm long (0.35 mm exclusive of the long lateral appendix), with a conspicuously long and a short and apically hooked lateral process on the right (ventral view); parameres completely reduced.

C o m p a r a t i v e n o t e s: Regarding both its external (small size, coloration, moderately long elytra) and its male sexual characters (shapes and chaetotaxy of sternite VII and VIII; aedaeagus strongly asymmetric and with conspicuous processes), G. multiplicus is highly similar to G. ramosus HERMAN, 1981 from Panama, from which it is reliably distinguished only by the shape of the aedaegus. For illustrations of G. ramosus see figures 345-350 in HERMAN (1981).

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 the northeast of Esmeraldas Province, northwestern Ecuador. The holotype was collected by sifting relatively dry leaf litter in a forest remnant at an altitude of approximately 100 m (BRACHAT pers. comm.).

Figures

Figs 32-37: Gnathymenus multiplicus nov.sp.: (32) forebody; (33) male sternite VII; (34) male sternite VIII; (35-37) aedeagus in lateral and in ventral view. Scale bars: 32: 0.5 mm; 33-37: 0.2 mm.