Pheidologitonetes bursata, Assing, 2017

Assing, Volker, 2017, On the Lomechusini fauna of the East Palaearctic and Oriental regions, with a focus on the genera Orphnebius and Amaurodera (Coleoptera: Staphylinidae: Aleocharinae), Beiträge Zur Entomologie = Contributions to Entomology 67 (1), pp. 63-106 : 90

Pheidologitonetes bursata spec. nov.

urn:lsid:zoobank.org:act:77C109C7-DED4-4297-95B4-519B7E085212

( Figs 7 , 39–40 , 105–109)

Type material: Holotype ♂: “ India, Kerala, Periyar Sanctuary, Thekkady , 1000 m, moist broad-leaved forest, 2.–5.I.1997, leg. Schulz & Vock / Holotypus ♂ Pheidologitonetes bursata sp. n., det. V. Assing 2016” (cAss) . Paratype ♀: “ India, Goa , Canacona distr., Cortigao Sanctuary, 100 m, primary forest, 6.–10.I.1997, leg. Schulz & Vock” (cAss) .

Etymology: The specific epithet is an adjective derived from the Latin noun bursa (bag, pouch) and alludes to the shape of the median lobe of the aedeagus.

Description: Body length 3.9–4.9 mm; length of forebody 1.7–2.1 mm. Coloration ( Figs 7 , 39–40 ): head dark-brown; pronotum reddish-brown; elytra reddish with the postero-lateral portion extensively darker; abdomen: tergite III yellowish; tergites IV–VI yellowish with a more or less extensive transverse infuscate band posteriorly; tergite VII dark-brown with the anterior margin yellowish; tergite VIII brown; antennae with the basal 4–5 antennomeres brown to dark-brown and antennomeres of the apical half gradually becoming paler, XI pale-brown to yellowish-brown; maxillary palpi yellowish, with the preapical palpomere brown.

Head ( Fig. 39 ) strongly transverse, 1.25–1.30 times as broad as long, posteriorly tapering towards posterior constriction practically behind eyes, i.e., without appreciable posterior angles; punctation fine and rather dense; interstices with fine and shallow microreticulation. Eyes large and bulging, much longer than distance from posterior margin of eye to posterior constriction of head. Antenna ( Fig. 7 ) 1.7–2.0 mm long; antennomeres IV–X of sub-cylindrical shape, of gradually decreasing length and decreasingly oblong, IV distinctly oblong, X weakly oblong or as long as broad.

Pronotum ( Fig. 39 ) 1.08–1.17 times as broad as long and 1.02–1.09 times as broad as head; lateral margins distinctly sinuate in posterior two-thirds; dorsal surface with microsculpture composed of minute and extremely dense microgranules (somewhat resembling microsculpture of pronotum in Amaurodera ) rendering the pronotum matt; antero-laterally with two long black setae, the anterior one near anterior angles and the posterior one at anterior third of pronotum.

Elytra ( Fig. 39 ) 0.75–0.82 times as long as pronotum, suture gaping posteriorly; punctation fine and dense; interstices with shallow microreticulation. Hind wings fully developed. Legs slender; metatarsus very slender and nearly as long as metatibia; metatarsomere I nearly as long as the combined length of II–IV.

Abdomen ( Fig. 40 ) narrower than elytra; tergites III–IV with, tergites V–VI without very shallow anterior impressions; tergites III–VI with a lateral and a postero-lateral long black seta on either side and with a pair of setiferous micropunctures in the middle of posterior margins, otherwise impunctate; tergite VII with dense and coarse sculpture composed of non-setiferous punctures posteriorly and somewhat confluent longitudinal impressions anteriorly (similar to sculpture of tergite VII in Orphnebius species ), posterior margin with pronounced palisade fringe; tergite VIII with dense and coarse granules, these granules denser anteriorly than posteriorly, posterior margin broadly truncate and a transverse row of marginal granules rendering the posterior margin serrate.

♂: sternite VIII with broadly and weakly convex posterior margin; median lobe of aedeagus ( Figs 105–106 ) 0.9 mm long, with long and voluminous basal portion (similar to the condition in the species of the Orphnebius hauseri group); ventral process short, with broad and pronounced semitransparent lateral extension in ventral view ( Fig. 107 ); paramere ( Fig. 108 ) small in relation to median lobe, 0.53 mm long, and of derived shape.

♀: sternite VIII with broadly convex posterior margin; spermatheca ( Fig. 109 ) small and comma-shaped.

Intraspecific variation: The female paratype is distinguished from the holotype by distinctly smaller size and a relatively smaller pronotum. However, in other characters the specimens are highly similar, suggesting that they are conspecific and that the observed differences should be interpreted as intraspecific variation.

Comparative notes: Based on the similarly derived morphology of the aedeagus and of the spermatheca, P. bursata is closely allied to P. adesi from Hong Kong, but distinguished by the shape of the head ( P. adesi : postocular region between posterior margin of eye and posterior angle of head approximately half as long as eye), a shorter and less massive antennomere I, much less pronounced microsculpture on the head, much finer sculpture on the pronotum, much more extensive non-setiferous punctation on tergite VII ( P. adesi : non-setiferous punctation confined to posterior half), a more broadly truncate and much more finely serrate posterior margin of tergite VIII, and by the primary sexual characters. For illustrations of P. adesi see figures 264–267 in PACE (1998).

Distribution and natural history: The type specimens were collected in two localities in Kerala and Goa provinces, Southwest India, in a broad-leaved forest and a primary forest at altitudes of 1000 and 100 m, respectively.

Figures

Figs 1–30: Antenna (1–19), forebody (20, 23, 26), abdomen (21, 24, 27, 29), antero-lateral portion of abdomen in lateral-dorsal view (22, 25, 28), and abdominal segment VII (30) of Orphnebius triacuminatus (1, 20–22), O. gracilis (2, 23–25), O. protuberatus (3, 26–28), O. pertortus (4, 29–30), O. reticulipennis (5), Zyrastilbus almorensis (6), Pheidologitonetes bursata (7), Rabdotodrusilla vara (8), Amaurodera bicarinata (9), A. gilvicornis (10), A. latisulcata (11), A. brevipes (12), A. migritheca (13), A. longisetosa (14), A. calicitheca (15), Drusilla smetanai (16), D. nepalensis (17), D. lativentris (18), and Witteia tensa (19). Scale bars: 1–29: 1.0 mm; 30: 0.5 mm.

Figs 31–42:Orphnebius pertortus(31),O. migrus(32–33),O. reticulipennis(34–36),Zyrastilbusalmorensis(37–38),Pheidologitonetes bursata (39–40), and Rabdotodrusilla vara (41–42): forebody (31–32, 34, 37, 39, 41); elytra and abdomen (33); abdomen (35, 38, 40, 42); antero-lateral portion of abdomen in dorso-lateral view (36). Scale bars: 37–38: 1.0 mm; 31–36, 39–42: 0.5 mm.

Figs 101–123: Pheidologitonetes setifer (101–104), P. bursata (105–109), Drusilla obliqua (110–113), D. nepalensis (114–116), and D. lativentris (117–123): male tergite VIII (101, 117); male sternite VIII (102, 118); female tergite VIII (103, 110–111, 114, 121); female sternite VIII (104, 112, 115, 122); median lobe of aedeagus in lateral and in ventral view (105–106, 119–120); apical portion of median lobe of aedeagus in ventral view (107); paramere (108); spermatheca (109, 113, 116, 123). Scale bars: 101–104, 110–112, 114–115, 117–122: 0.5 mm; 105–108, 113, 116, 119–120: 0.2 mm; 109, 123: 0.1 mm.