Tetrabothrus sulawesicus, 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 : 102-103

Tetrabothrus sulawesicus spec. nov.

( Figs 167–169 , 342–454 )

Type material: Holotype ♂: “ Indonesia: Sulawesi-Utara , Dumoga-Bone N.P ., November 1985 / Plot A, ca 200 m, Lowland forest / Flight interception trap / R. Ent. Soc. Lond., Project Wallace, B.M. 1985-17 / Holotypus ♂ Tetrabothrus sulawesicus sp. n., det. V. Assing 2016 ” ( BMNH).

Paratypes: 1 ♀: same data as holotype (cAss) ; 1 ♂: same data, but “ October 1985 ” ( BMNH) ; 1 ♀: same data, but “ 24 Februar 1985 ” ( BMNH) ; 1 ♂, 1 ♀: same data, but “ April 1985 / Plot B, ca 300 m ” ( BMNH, cAss) .

Comment: The specific epithet (adjective) is derived from Sulawesi, the Indonesian island where the species was discovered.

Description: Body length 4.5–6.0 mm; length of forebody 1.9–2.5 mm. Coloration: head and pronotum variable, bright-reddish to blackish-brown; elytra blackish-brown; abdomen variable, reddish to black; legs bicoloured: femora pale yellowish with the apices – especially those of the metafemora rather broadly – brown to blackishbrown, tibiae and tarsi brown; antennae black with antennomeres I–III and at least the apex of XI reddish; maxillary palpi yellowish.

Head ( Fig. 167 ) strongly transverse, 1.25–1.30 times as broad as long; posterior angles obsolete; punctation extremely fine and moderately dense, except along the impunctate middle of the dorsal surface; pubescence long and pale. Eyes large, approximately as long as distance from posterior margin of eye to posterior constriction of head. Antenna ( Fig. 168 ) 1.2–1.3 mm long.

Pronotum ( Fig. 167 ) weakly transverse, 1.06–1.15 times as broad as long and 1.02–1.08 times as broad as head, strongly convex in cross-section; punctation fine and moderately dense; pubescence pale, long, and suberect.

Elytra ( Fig. 167 ) 0.85–0.90 times as long as pronotum; punctation denser and less fine than that of pronotum; pubescence very long and suberect. Hind wings fully developed. Metatarsomere as long as the combined length of metatarsomeres II and III.

Abdomen ( Fig. 169 ) narrower than elytra and with moderately deep anterior impressions on tergites III– VI; tergites III–VII each with four setiferous punctures at posterior margins; tergite VII without non-setiferous punctation, posterior margin with palisade fringe; tergite VIII with dense fine setiferous punctures near anterior margin, otherwise impunctate.

♂: posterior margin of sternite VIII strongly produced, convexly pointed in the middle ( Fig. 454 ); median lobe of aedeagus ( Figs 452–453 ) 0.53–0.58 mm long; ventral process subapically weakly curved in lateral view and rather narrow in ventral view; paramere nearly 0.6 mm long, its apical lobe of moderate length and slender.

Comparative notes: Tetrabothrus sulawesicus is reliably distinguished from other congeners with bicoloured legs and without non-setiferous punctation on tergite VII (and VIII) only by the shape of the median lobe of the aedeagus, from most species also by the more strongly pointed posterior margin of the male sternite VIII. It additionally differs from T. clavatus , the only other representative of the genus recorded from Sulawesi, by smaller and less bulging eyes, bicoloured legs, and darker antennomeres IV–IX.

Distribution and natural history: The type locality, today Bogani Nani Wartabone National Park, is situated on Minahassa Peninsula in the north of Sulawesi, Indonesia. The specimens were collected with flight interception traps in lowland forests at altitudes of 200 and 300 m.

Figures

Figs 160–180. Tetrabothrus borneensis, holotype (160–162), T. punctiventris (163–166), T. sulawesicus (167–169), Zyras illecebrosus, paratype (170–172), Z. gibbus, holotype (173–177), and Z. quasar, holotype (178–180): forebody (160, 163, 167, 170, 173, 178); antenna (161, 164, 168, 171, 174, 179); abdomen (162, 165, 169, 172, 175, 180); tergite VIII (166); tergite III (176); tergites VII– VIII (177). Scale bars: 160–165, 167–175, 178–180: 1.0 mm; 166, 176–177: 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.

Figs 359–378. Orphnebius laticeps (359–361), O. biimpressus (362–364), O. ulcerosus (365–369), O. falagrioides (370–372), and Drusilla bifida (373–378): tergite VIII (359, 362, 368, 370, 374); female sternite VIII (360, 363, 371); spermatheca (361, 364, 372); median lobe of aedeagus in lateral and in ventral view (365–366, 376–377); paramere (367); male sternite VIII (369, 375); posteromedian portion or head (373); apex of ventral process of aedeagus (378). Scale bars: 359–372, 374–377: 0.2 mm; 373, 378: 0.1 mm.

Figs 379–395. Drusilla bifida (379), Rabdotodrusilla pectinata (380–383), Amaurodera arunica (384–388), A. gilvios (389–390, 395), and A. reticulata (391–394): sutural portion of left elytron (379); median lobe of aedeagus in lateral and in ventral view (380– 381, 385–386, 389–392); male tergite VIII (382); male sternite VIII (383); male pronotum (384); spermatheca (387–388, 395); subapical portion of median lobe of aedeagus in dry preparation (393); subapical portion of median lobe of aedeagus in transparent light (394). Scale bars: 384: 0.5 mm; 379–383, 385–392, 395: 0.2 mm; 393–394: 0.1 mm.

Figs 396–419. Amaurodera dentata (396–399), A. parvoculata (400–404), A. thailandensis (405–410), A. fasciata (411–414), and A. meorum (415–419: 415–416, 419:Khao Yai Nat.Park):median lobe of aedeagus in lateral and in ventral view (396–397, 400–402, 405–409, 411–412, 415–418); spermatheca (398–399, 403–404, 410, 413–414, 419). Scale bars: 0.2 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.

Figs 442–458. Tetrabothrus collucatus (442–443), T. borneensis (444–449), T. punctiventris (450–451), T. sulawesicus (452–454), Zyras illecebrosus, paratype (455–456), and Z. quasar, holotype (457–458): median lobe of aedeagus in lateral and in ventral view (442–445, 450–453, 455–458); apico-ventral portion of median lobe in lateral view (446–448); male sternite VIII (449, 454). Scale bars: 0.2 mm.