Mimogonellus dreybrodti, Steiner, 2017

Steiner, Helmut, 2017, Mimogonellus dreybrodti sp. n., a new cave-inhabiting Osoriinae from Laos (Coleoptera: Staphylinidae), Zootaxa 4337 (1) : -

Mimogonellus dreybrodti , new species ( Figs 1–2 )

Type material. Holotype: LAOS: ♂: ‘111/09-, 13.01.2009, N20°14'56.2", E103°23'47", (Tham Nam Lot, S. Ban Boumfart Village ), Vieng Thong, H (o)uaphan(h) Prov. , Laos, Col : H. Steiner, Northern Laos-European Cave Project 2009’ ( SNUC) . Paratypes: LAOS: 2 ♂♂, same collecting data as the holotype ( SNUC) .

Comparative diagnosis. Mimogonellus dreybrodti can be readily separated from the two Asian congeners, i.e., M. japonicus Naomi , and M. yasutoshii Naomi , by the much larger body size (4.96–5.13 mm vs. 3.0– 3.2 mm), more strongly curved aedeagal median lobe, and much longer parameres each exceeding the apex of the median lobe.

Description. Male. Body ( Fig. 1A ) elongate, cylindrical; length 4.96–5.13 mm; forebody length 2.40–2.42 mm; reddish brown to dark reddish brown, tarsi and mouthparts lighter in color.

Head ( Fig. 1B ) longer than wide, length 0.76–0.81 mm, width 0.72–0.74 mm; dorsum sparsely covered with large and shallow punctures, with long and yellow setae directed posteriorly, surface of disc between punctures polished and lacking microsculpture; mediobasal portion, area posterior to eyes, genae, and gular area with dense reticulate microsculpture; gular suture divergent for short distance at base, fused anteriorly; eyes slightly prominent, reniform in lateral view, each eye composed of about 130 ommatidia. Antennae ( Fig. 1C ) reaching 1/3 elytral length when stretched posteriorly; antennomeres I–III distinctly elongate, III longer than II and IV, IV–X successively stouter, moniliform, XI longer than X, narrowed apically.

Pronotum ( Fig. 1B ) about as broad as elytra, transverse, widest at middle, strongly constricted at base; length 0.69– 0.73 mm, width 0.89–0.96 mm; with punctures and setae similar to those on head, with reticulate microsculpture along posterolateral and posterior margins. Mesoscutellum roundly triangular, with reticulate microsculpture.

Elytra ( Fig. 1B ) about as long as wide, length 0.88–0.95 mm, width 0.92–0.93 mm; parallel sided; sparsely punctate, punctures shallower than those of pronotum; basal area lateral to mesoscutellum with reticulate microsculpture.

Legs short; profemora projected ventrally at basal half; protibiae ( Fig. 2A ) curved at basal 1/3, with seven external and two apical spines, with well-developed ctenidium along mesal margin; mesotibia ( Fig. 2B ) with lateral row of macrosetae, with two external and two apical spines; metatibia with apicolateral row of macrosetae, and two apical spines.

Abdomen slightly broadened posteriorly; punctation and setation similar to those on elytra, but sparser and finer, also with dense reticulate microsculpture. Paired tergite IX ( Fig. 2C ) with several exceptionally elongate lateral setae; tergite X ( Fig. 2C ) strongly protruding posterolaterally, with two small denticles at posterior margin. Sternites VII–VIII lacking median impression; sternite VIII ( Fig. 2D ) subtriangular, each side with few long setae and two small, acute denticles; sternite IX ( Fig. 2E ) elongate, weakly sclerotized, apex rounded and finely denticulate.

Aedeagus ( Fig. 2F–G ) elongate, length of median lobe 0.56 mm, length including parameres 0.64 mm; median lobe weakly sclerotized at basal half, apical half strongly curved dorsally and narrowed apically; parameres long, exceeding apex of median lobe, each paramere with two long macrosetae at apex; endophallus with three sclerites, elongate, twisted, and spiral-like.

Female. Unknown.

Distribution. Northern Laos: Houaphanh.

Etymology. We dedicate this new species to Dr. Joerg Dreybrodt ( Germany), a specialist in survey and mapping, and the coordinator of the 2009–2010 survey team.

Figures

FIGURE 1. Mimogonellus dreybrodti, male. A. Dorsal habitus. B. Forebody. C. Left antenna. Scale bars: 2 mm in A; 0.5 mm in B – C.

FIGURE 2. Mimogonellus dreybrodti, male. A. Protibia. B. Mesotibia. C. Tergites IX – X. D. Sternite VIII. E. Sternite IX. F – G. Aedeagus, in lateral (F), and dorsal (G) views. Scale bars: 0.3 mm in A – D; 0.2 mm in E – G.