Orphnebius (Deroleptus) dispar, 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 : 73

Orphnebius (Deroleptus) dispar spec. nov.

( Figs 65 , 106, 110–111 , 354–358 )

Type material: Holotype ♂: “ NE India , Arunachal Pr. , Etalin vicinity, 700 m, 28°36'56"N, 95°53'21"E, FIT (flight interception trap), L. Dembický leg., 12.–25.v.2012 / Holotypus ♂ Orphnebius dispar sp. n., det. V. Assing 2015” ( ZFMK).

Paratypes: 5 ♀♀: same data as holotype ( ZFMK, cAss) ; 1 ♂: “ NE-India , Meghalaya, Tura Peak , 600–1000 m, 25°30'N 90°14'E, L. Dembický leg., 12.–22.vi.2007 ” ( NHMB) .

Etymology: The specific epithet (Latin, adjective: disparate, dissimilar) alludes to the pronounced sexual dimorphism of the abdominal sternite III.

Description: Body length 3.0– 3.5 mm; length of forebody 1.2–1.5 mm. Coloration: body black; legs brown with dark-brown femora; antennae blackish-brown with antennomeres I–III yellowish-red; maxillary palpi reddish-yellow with the apical palpomere yellowish.

Head ( Fig. 106 ) strongly transverse, approximately 1.4 times as broad as long; posterior angles moderately marked; punctation very fine and sparse; median dorsal portion impunctate; interstices without microsculpture. Eyes very large, approximately three times as long as postocular region from posterior margin of eye to posterior angle. Antenna ( Fig. 65 ) 0.9–1.0 mm long and slender; antennomere IV weakly transverse; antennomeres V–X of gradually increasing width and increasingly transverse; X slightly more than 1.5 times as broad as long; XI approximately as long as the combined length of IX and X.

Pronotum ( Fig. 106 ) approximately 1.4 times as broad as long and as broad as head, moderately convex in crosssection; lateral margins each with three long and black erect setae; disc with fine and sparse punctation.

Elytra ( Fig. 106 ) 1.10–1.15 times as long as, and much broader than pronotum; punctation sparse and distinct, partly somewhat granulose. Hind wings fully developed. Metatarsomere I approximately as long as the combined length of II–IV.

Abdomen ( Figs 110–111 ) narrower than elytra; sternite III with pronounced sexual dimorphism; tergites III–VI practically impunctate; tergite VII with dense non-setiferous punctation in posterior three-fifths, near anterior margin with a transverse row of four to six granules, posterior margin with distinct palisade fringe; tergite VIII ( Fig. 357 ) with a pair of median and approximately six setiferous granules at posterior margin, posterior margin with four blunt tooth-like processes.

♂: sternite III postero-laterally with pronounced spineshaped process; median lobe of aedeagus ( Figs 354–355 ) small, 0.28 mm long and of simple shape; paramere ( Fig. 356 ) nearly 0.3 mm long, with long paramerite and very short spine-shaped condylite.

♀: sternite III postero-laterally slightly produced, but not spine-shaped; spermatheca ( Fig. 358 ) small and of simple, but distinctive morphology.

Comparative notes: Among congeners of similarly small size and dark coloration, this species is characterized particularly by the sparse and partly somewhat granulose punctation, the sexual dimorphism of sternite III, the modifications of the tergites VII and VIII, and by the shapes of the aedeagus and the spermatheca. Species with similar external and sexual characters are unknown to me. Distribution and natural history: Orphnebius dispar is currently known from two localities in Arunachal Pradesh and Meghalaya, northeastern India. The specimens from the type locality were collected with a flight interception trap at an altitude of 700 m, together with O. spinans and an unnamed Orphnebius species. The paratype from Meghalaya was found at an altitude between 600 and 1000 m, together with O. niger .

Figures

Figs 54–83. Antenna (54–69), forebody (70–73), abdomen (74–76), abdominal segments III–V (77, 81), lateral portion of abdominal segments III–V (78, 82), tergites VI–VII (79, 83), and hind leg (80) of Orphnebius spp. of the subgenus Deroleptus: discrepans (54, 73, 75), triapicalis (55, 71, 76), gracilior (56, 72, 77–80), sexcarinatus (57, 81–83), spoliatus (58), cultellatus (59), septemcuspis (60), vates (61), tortus (62), baccillatus (63), carinatus (64), dispar (65), laticeps (66), biimpressus (67), ulcerosus (68), falagrioides (69), siamensis (70, 74). Scale bars: 70–83: 1.0 mm; 54–69: 0.5 mm.

Figs 102–118. Forebody (102–108), abdomen (109–110, 112–113, 115), lateral portion of abdominal segments III–V/ VII (111, 117–118), and tergites VII(–VIII) (114, 116) of Orphnebius spp. of the subgenus Deroleptus: carinatus (102, 117), laticeps (103, 112), biimpressus (104, 108, 113–114), ulcerosus (105, 115–116), dispar (106, 110–111), falagrioides (107, 118), baccillatus (109). Scale bars: 102–110, 112–113, 115, 117–118: 1.0 mm; 111, 114, 116: 0.5 mm

Figs 340–358. Orphnebius vates (340–344), O. tortus (345–347), O. baccillatus (348–350), O. carinatus (351–353), and O. dispar (354–358): median lobe of aedeagus in lateral and in ventral view (340–341, 354–355); paramere (342, 356); tergite VIII (343, 345, 348, 351, 357); male sternite VIII (344); female sternite VIII (346, 349, 352); spermatheca (347, 350, 353, 358). Scale bars: 0.2 mm.