Orphnebius fodens, 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 : 61

Orphnebius fodens spec. nov.

( Figs 13 , 48 , 283–286 )

Type material: Holotype ♂ [antennomeres XI of both antennae missing]: “ Malaysia, Sabah, Sandakan, S. Lokan (LF), Sept. 96 AYC Chung / FIT 3/2/2 / BMNH {E} 2002-113, A. Y. C. Chung, LF = Logged Forest / Holotypus ♂ Orphnebius fodens sp. n., det. V. Assing 2016 ” ( BMNH).

Etymology: The specific epithet is the present participle of the Latin verb fodere (to sting) and alludes to the conspicuously acute ventral process of the aedeagus.

Description: Body length 3.2 mm; length of forebody 1.4 mm. Coloration: head and pronotum brown; elytra and abdomen pale-reddish; legs reddish-yellow; antennae reddish; maxillary palpi yellowish.

Head ( Fig. 48 ) strongly transverse, 1.3 times as broad as long, and of transversely oval shape; posterior angles completely obsolete; dorsal surface practically impunctate, except for some fine punctures in lateral portions. Eyes large and bulging, approximately twice as long as distance from posterior margin of eye to posterior constriction of head. Antenna ( Fig. 13 ) strongly incrassate and not distinctly asymmetric; antennomeres IV–X strongly transverse, of increasing width, and increasingly transverse, X nearly three times as broad as long.

Pronotum ( Fig. 48 ) strongly transverse, 1.35 times as broad as long and 1.17 times as broad as head; lateral and posterior margins nearly forming a semi-circle, posterior angles practically obsolete; disc with a median pair of punctures, otherwise impunctate; lateral margins each with three very long and erect black setae.

Elytra ( Fig. 48 ) approximately 0.85 times as long as pronotum; disc with moderately sparse and moderately fine punctation; pubescence fine, pale, and sub-erect. Hind wings fully developed. Tarsi relatively short; metatarsomere I approximately as long as the combined length of II and III.

Abdomen: tergites IV–VI each with 5–6 setiferous tubercles at posterior margins, these tubercles bearing long dark setae; tergite VII with pronounced, dense and long striae, posterior margin with palisade fringe; tergite VIII ( Fig. 286 ) anteriorly with short pubescence, in posterior half with two transverse rows of eight long black setae, posterior margin broadly truncate; posterior margin of sternite VIII weakly convex in the middle.

♂: hemi-tergites IX of moderate length; hemi-tergites IX and tergite X with dense and long pubescence; median lobe of aedeagus ( Figs 283–284 ) 0.5 mm long, with very slender and acute ventral process; internal structures small and moderately sclerotized; paramere ( Fig. 285 ) barely 0.35 mm long, paramerite and condylite basally broad and apically tapering, of subequal length.

♀: unknown.

Comparative notes: Based on the similar sculpture of tergite VII, similarly small size, similar head shape and large eyes, and particularly on the similar morphology of the median lobe of the aedeagus, O. fodens is closely allied to O. retunsus , from which it differs by a less transverse head, a broader pronotum (in relation to head), shorter elytra, the sculpture of tergite VII (striae longer, posteriorly without non-setiferous punctation), as well as by the different male primary sexual characters.

Distribution and natural history: The type locality is situated near Sandakan in Sabah, Borneo. The holotype was collected with a flight interception trap.

Figures

Figs 1–26. Antenna (1–21) and forebody (22–26) of Orphnebius spp. of the O. hauseri group: spinans (1, 23), cernens (2, 24), lunatus (3, 25), bakeri (4, 26), breviceps (5), extensus (6), serratus (7), integer (8), bicuspis, Laos (9), bicuspis, NE India (10), fusicollis (11), retunsus (12), fodens (13), opticus (14), dilatatus (15), fuscapicalis (16), grandicollis (17, 22), reductus (18), biformis, male (19), biformis, female (20), effeminatus (21). Scale bars: 22–26: 1.0 mm; 1–21: 0.5 mm.

Figs 40–53. Forebody (40–50), abdomen (51), and antenna (52–53) of Orphnebius spp. of the O. hauseri group (40–49) and of the subgenus Deroleptus (50–53): opticus (40), effeminatus (41), biformis, male (42), biformis, female (43), bicuspis, NE India (44), retunsus (45), fusicollis (46–47), fodens (48), reductus (49), niger (50–52), siamensis (53). Scale bars: 1.0 mm.

Figs 277–295. Orphnebius biformis (277–278), O. retunsus (279–282), O. fodens (283–286), O. effeminatus (287–292), and O. multimpressus (293–295): median lobe of aedeagus in lateral and in ventral view (277–280, 283–284, 287–288, 293–294); paramere (281, 285, 289, 295); tergite VIII (282, 286, 290); median portion of tergite VIII (291); male tergites IX-X (292). Scale bars: 0.2 mm.