Amaurodera bulbosa PACE, 2008

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 : 98

Amaurodera bulbosa PACE, 2008

( Figs 164–165 )

Amaurodera bulbosa PACE, 2008a: 119 f.

Amaurodera discoidea PACE, 2008a: 121 f., partim.

Type material examined: A. bulbosa : Holotype ♀: “♀ / SABAH: Poring Hot Springs , 500 m, 11.V.1987, Burckhardt - Löbl / Holotypus Amaurodera bulbosa mihi, det. R. Pace 2000 / Amaurodera bulbosa n. sp., det. R. Pace 2000” ( MHNG) . Paratype ♀: same data as holotype ( MHNG).

A. discoidea : Paratypes: 2 ♂♂: “♂ / SABAH: Poring Hot Springs , 500 m, 13.V.1987, Burckhardt - Löbl / Paratypus Amaurodera disoidea mihi, det. R. Pace 2000 / Amaurodera discoidea n. sp., det. R. Pace 2000 / Amaurodera bulbosa Pace , det. V. Assing 2016” ( MHNG, cAss); 1 ♂: same data, but “ 7.V.1987 ” ( MHNG).

Comment: The original description of A. bulbosa is based on two females from “ Sabah, Poring Host Springs, 500 m ” ( PACE 2008a). The male paratypes of A. discoidea , which were collected in the type locality of A. bulbosa , belong to this species, too.

Redescription: Body length 3.8–4.4 mm; length of forebody 1.9–2.2 mm. Other measurements: head width: 0.54–0.62 mm; length of pronotum: 0.78–0.85 mm; width of pronotum: 0.57–0.63 mm; elytral length at suture: 0.45–0.48 mm; elytral width: 0.80–0.85 mm. Coloration: head and pronotum reddish-brown to blackish-brown; elytra pale-reddish to reddish-brown with the posterolateral portions more or less extensively, diffusely darker; abdomen with segments III–IV, or III–V, and VIII–X and the posterior portion of VII reddish to brown, and the remainder dark-brown to blackish-brown; legs yellowish; antennae pale-brown to brown with the basal three antennomeres yellowish-red and the apical antennomeres more or less extensively dark-yellowish; uniformly yellowish or with all or some of antennomeres IV–VIII darker; maxillary palpi yellowish-red with the terminal palpomere yellowish.

Head 1.08–1.14 times as long as broad; postero-lateral outline between eyes and posterior constriction convex in dorsal view; median dorsal portion not impressed; punctation sparse and vey fine; interstices without microreticulation.Eyes small, one-third to half as long as distance from posterior margin of eye to posterior constriction in dorsal view. Antenna long and slender, 2.2–2.4 mm long; antennomere IX twice as long as broad and antennomere X more than 1.5 times as long as broad.

Pronotum slender, 1.44–1.48 times as long as broad, probably without sexual dimorphism; dorsal surface with very dense microgranules and opaque; midline with deep and narrow median sulcus reaching neither anterior nor posterior margins; antero-lateral portions with three long and rather stout setae on either side and with scattered very short and fine setae.

Elytra 0.56–0.58 times as long as pronotum; punctation extremely fine (barely noticeable even at high magnification) and moderately dense; microreticulation absent. Hind wings fully developed. Legs including tarsi long and slender; metatarsomere I approximately as long as the combined length of II and III.

Abdomen narrower than elytra; tergites III–V with moderately deep anterior impressions; punctation and pubescence very sparse; tergal surfaces without distinct microsculpture, indistinct shallow traces of microsculpture composed of transverse meshes may be visible only on anterior tergites at high magnification (100 x); posterior margin of tergite VII with palisade fringe; posterior margin of tergite VIII weakly convex and serrate.

♂: median lobe of aedeagus ( Figs 164–165 ) small, 0.38– 0.44 mm long; ventral process short and sinuate in lateral view, broad and apically rounded in ventral view.

♀: spermatheca of similar shape as in A. kraepelini , with the proximal portion of the capsule distinctly dilated (see figure 27 in PACE 2008a).

Comparative notes: Amaurodera bulbosa differs from A. discoidea , with which it was confounded by PACE (2008a), by numerous characters, particularly much smaller eyes ( A. discoidea : eyes large and strongly bulging, at least as long as postocular region from posterior margin of eye to posterior constriction of head), smaller body size ( A. discoidea : body length 5.0 mm; length of forebody 2.4 mm; length of pronotum 0.90 mm), the chaetotaxy of the pronotum (antero-lateral portions with only two long setae on either side, these setae finer and shorter than in A. bulbosa , and with numerous short setae), uniformly yellowish legs ( A. discoidea : meso- and metafemora apically infuscate), a less distinctly bicoloured abdomen, the morphology of the aedeagus, and the completely different shape of the spermatheca.

Distribution and natural history: This species is currently known only from the type locality in Sabah (altitude: 500 m). Amaurodera frondium and A. calicitheca were found in the same locality.

Figures

Figs 150–172: Amaurodera frondium (150–151), A calicitheca (152–158), A. discoidea, paratype (159), A. longisetosa (160–163), A. bulbosa (paratypes of A. discoidea from Sabah) (164–165), Rabdotodrusilla vara (166–169), and Witteia tensa (170–172): median lobe of aedeagus in lateral and in ventral view (150–155, 160–162, 164–165, 168–169, 170–171); apical portion of median lobe in ventral view (156); spermatheca (157–159, 163, 172); male tergite VIII (166); male sternite VIII (167). Scale bars: 150–155, 157–165: 0.5 mm; 166–172: 0.2 mm; 156: 0.1 mm.