Drusilla bispinosa, Assing, 2019

Assing, Volker, 2019, On the Lomechusini fauna of the Palaearctic and Oriental regions. XXVI. New species, a new synonymy, and additional records (Coleoptera: Staphylinidae: Aleocharinae), Beiträge Zur Entomologie = Contributions to Entomology 69 (1), pp. 33-70 : 57

Drusilla bispinosa spec. nov.

urn:lsid:zoobank.org:act:A3E4F51F-809D-407F-9DE0-5655A67106AC

( Figs 35–43 , 129–131)

Type material: Holotype: “ MALAYSIA 2011 PAHANG, Cameron Highlands, Tanah Rata vill. env., 1500–1600 m, FIT, R. Hergovits leg. 4.iv.2011 / Holotypus Drusilla bispinosa sp. n., det. V. Assing 2017” ( MMB) . Paratypes: 27 exs.: same data as holotype (MMB, cAss).

Etymology: The specific epithet (Latin, adjective) alludes to the presence of two pronounced spines on the male abdominal tergite III.

Description: Large species; body length 6.7–9.3 mm; length of forebody 3.3–4.0 mm. Coloration: forebody blackish-brown to blackish; abdomen blackish-brown, with segments II–V often reddish to reddish-brown; legs yellow; antennae blackish-brown to black with antennomere II usually reddish to reddish-brown; maxillary palpi pale-brown to brown with the apical palpomere yellow.

Head ( Fig. 35 ) transverse, 1.15–1.20 times as broad as long; punctation fine and rather dense; interstices with fine microreticulation. Eyes large, much longer than distance from posterior margin of eye to posterior constriction in dorsal view. Antenna ( Fig. 36 ) elongate and slender, approximately 3.5 mm long; antennomeres IV–X all approximately twice as long as broad.

Pronotum ( Fig. 35 ) slender, 1.05–1.16 times as long as broad and 1.01–1.10 times as broad as head, broadest in anterior half; sexual dimorphism weakly pronounced; along midline with sharp and narrow sulcus; lateral margins strongly sinuate in dorsal view; posterior angles pronounced; punctation dense and distinct, regularly distributed; interstices on average slightly narrower than diameter of punctures and with shallow microreticulation visible only at high magnification.

Elytra ( Fig. 35 ) 0.80–0.85 times as long as pronotum; laterally with a sharp carina on either side; punctation and microsculpture similar to that of pronotum. Hind wings fully developed. Legs slender; metatarsomere I nearly as long as the combined length of II–IV.

Abdomen ( Fig. 37 ) narrower than elytra; tergite III with pronounced sexual dimorphism; tergites II–III with numerous punctures; tergites IV–VII with few scattered punctures anteriorly, on discs, and at posterior margins, as well as with scattered micropunctation, otherwise impunctate; all tergites with shallow and fine transverse microsculpture; tergite VII sexually dimorphic, posterior margin with palisade fringe; tergite VIII sexually dimorphic.

: pronotum somewhat depressed on either side of the median sulcus and near posterior angles; abdominal tergite III ( Figs 38–39 ) with a pronounced spine of variable shape on either side; tergite VII ( Figs 40–42 ) with a median tubercle or a median carinae posteriorly; tergite VIII ( Figs 40–42 ) with a pronounced median tubercle posteriorly, posterior margin concave and conspicuously angled laterally; median lobe of aedeagus approximately 0.9 mm long and shaped as in Figs 129–130.

: tergites III and VII unmodified; posterior margin of tergite VIII produced and with three tooth-like projections ( Fig. 43 ); spermatheca as in Fig. 131.

Comparative notes: This distinctive species is characterized particularly by the slender habitus and large body size, by the distinctive modifications of the male tergites III and VII, by the shapes of the male and female tergite VIII, and by the primary sexual characters.

Distribution and natural history: The type locality is situated in Pahang Province, Peninsular Malaysia. The specimens were collected with a flight interception trap at an altitude of 1500–1600 m.

Figures

Figs 35–52: Drusilla bispinosa (35–43), D. shavrini (44–47), and D. penicillata (48–52): male forebody (35, 45, 49); antenna (36, 46, 51); male abdomen (37, 47, 52); anterior portion of male abdomen (38–39); posterior portion of male abdomen in dorsal and in lateral view (40–42); posterior portion of female abdomen (43); habitus (44, 48); head in dorso-lateral view (50). Scale bars: 35–49, 51–52: 1.0 mm; 50: 0.5 mm.