Amaurodera disparicollis, Assing, 2016

Assing, Volker, 2016, On some Lomechusini of the Palaearctic and Oriental regions (Coleoptera: Staphylinidae: Aleocharinae), Beiträge Zur Entomologie = Contributions to Entomology 66 (1), pp. 13-111 : 90-91

Amaurodera disparicollis spec. nov.

( Figs 141 , 150–151 , 423–429 )

Type material: Holotype ♂: “ Sumatra: Jambi, km 15 Sungaipenuh to Tapan, 1450 m, 9.XI.1989, Agosti, Löbl, Burckh. #10 / Holotypus ♂ Amaurodera disparicollis sp. n., det. V. Assing 2015” ( MHNG).

Paratype ♀: same data as holotype (cAss) .

Etymology: The specific epithet (Latin, adjective: with different pronotum) alludes to the pronounced sexual dimorphism of the pronotum.

Description: Body length 5.5–5.8 mm; length of forebody 2.6–2.7 mm. Coloration: forebody brown to dark-brown; abdomen reddish-brown to brown, with segments VI– VII slightly darker; legs yellowish, with the profemora pale-brown, the mesofemora brown with yellowish bases, and the metafemora brown with the basal third yellowish; antennae uniformly yellowish or pale-brown with the apical antennomeres yellowish; maxillary palpi yellowish-brown with the terminal palpomere yellowish.

Head ( Figs 150–151 ) oblong, 1.06–1.10 times as long as broad, broadest across eyes, with moderate sexual dimorphism; punctation sparse and extremely fine; interstices without microreticulation. Eyes of moderate size, 0.6–0.7 times as long as distance from posterior margin of eye to posterior constriction of head. Antenna ( Fig. 141 ) 3.1–3.2 mm long; antennomere IX twice as long as broad.

Pronotum ( Figs 150–151 ) 1.04–1.06 mm long, 1.36– 1.41 times as long as broad, and 1.06–1.09 times as broad as head, with rather pronounced sexual dimorphism; dorsal and lateral surface meeting at an obtuse angle posteriorly; anterior one-sixth to one-fifth of dorsal surface with very shallow microreticulation and glossy; microreticulation reaching lateral margins neither anteriorly nor posteriorly; narrow median furrow anteriorly terminating at some distance from anterior margin of pronotum.

Elytra ( Figs 150–151 ) 0.55–0.56 times as long as pronotum; punctation extremely fine and moderately sparse; interstices with nearly obsolete microreticulation, traces of which may be visible at high magnification (100 x); pubescence moderately long and semi-erect. Hind wings present. Metatarsomere I approximately as long as the combined length of II and III.

Abdomen narrower than elytra; punctation fine and very sparse on all tergites; tergites III–V with shallow, nearly obsolete microsculpture composed of transverse meshes, tergites VI–VIII without appreciable microreticulation (except near anterior margins); posterior margin of tergite VII with palisade fringe; posterior margin of tergite VIII distinctly serrate.

♂: head shallowly impressed along the middle; pronotum ( Figs 423–424 ) antero-laterally with an oblique elevation on either side, antero-median portion impressed and extensively glossy; median lobe of aedeagus ( Figs 427–428 ) large, 1.0 mm long; ventral process rather broad in ventral view; paramere 0.93 mm long, with rather short, broad, and flattened apical lobe.

♀: head with shallow median impression, this impression somewhat shorter than in male; pronotum ( Figs 425-426 ) without antero-lateral elevations, in antero-median portion not impressed and much less extensively glossy; spermathecal capsule ( Fig. 429 ) with weakly dilated distal portion and with large and proximally distinctly dilated proximal portion.

Comparative notes: This species is characterized particularly by relatively large size, long antennae, the secondary sexually dimorphic head and pronotum, and a large median lobe of the aedeagus. Previously, the sole representative of the genus known from Sumatra was A. nigra CAMERON, 1925 , which is distinguished from A. disparicollis by smaller size and darker coloration alone.

Distribution and natural history: The type locality (approximately 2°02'S, 101°18'E) is situated in the southwest of Sumatra ( Indonesia), near the border between Jambi and Sumatera Barat. The specimens were collected at an altitude of 1450 m, together with the following species and a male of an unnamed species.

Figures

Figs 119–143. Drusilla bifida (119–122), Rabdotodrusilla pectinata (123–125), Amaurodera arunica (126–127, 132), A. gilvios (128, 133), A. reticulata (129, 134), A. dentata (130, 135), A. parvoculata (131, 136), A. thailandensis (137–138), A. fasciata (139), A. meorum(140),A. disparicollis (141), A. spinans (142),andA. varicollis(143):forebody (119, 123, 126, 128–131); head and pronotum (120); antenna (121, 124, 132–143); abdomen (122, 125, 127). Scale bars: 1.0 mm.

Figs 144–159. Amaurodera thailandensis (144–145), A. fasciata (146), A. meorum (147), A. spinans (148), A. varicollis (149), A. disparicollis, male (150), A. disparicollis, female (151), Tetrabothrus nilgiricus (152–153), T. pubescens, syntype (154–156), T. collucatus (157–158), and T. neoguineensis, holotype (159): forebody (144–152, 154, 157, 159); abdomen (153, 156); antenna (155, 158). Scale bars: 144–154, 156–157, 159: 1.0 mm; 155, 158: 0.5 mm.

Figs 420–441. Amaurodera meorum (420–422), A. disparicollis (423–429), A. spinans (430–431), A. varicollis (432–434), Tetrabothrus nilgiricus (435–436), T. indicus (437–439; 439: lectotype), andT. inflexus fromLaos (440–441): spermatheca (420–422, 429, 434); male pronotum (423–424); female pronotum (425–426); median lobe of aedeagus in lateral and in ventral view (427–428, 430–433, 435–437, 440); ventral process of aedeagus (438–439, 441). Scale bars: 423–426: 1.0 mm; 420–422, 427–441: 0.2 mm.