Angustanillus armatus, Giachino & Eberhard & Perina, 2021

Giachino, Pier Mauro, Eberhard, Stefan & Perina, Giulia, 2021, A rich fauna of subterranean short-range endemic Anillini (Coleoptera, Carabidae, Trechinae) from semi-arid regions of Western Australia, ZooKeys 1044, pp. 269-337 : 269

Angustanillus armatus sp. nov. Figs 49-51

Type locality.

WA, Pilbara, 38 km W of Pannawonica, Mesa B, 21°39'36"S, 115°57'20"E.

Type series.

HT ♂, WA, Pilbara, 38 km W of Pannawonica, Mesa B (bore hole MEBRC0021), 21°39'36"S, 115°57'20"E (GPS WGS84), March-May 2005; M. Greenham, D. Kamien, L. Mould, Western Australian Entomology Reg. no. 64217 (WAM).

Differential diagnosis.

Large sized species (TL mm 2.66), easily distinguishable from A. striatipennis by: elytra without distinct striae, but with a series of short and longitudinally aligned setae; only one discal seta; pronotum and elytra surface without distinct punctures; and more elongated pronotum.

Description of the HT ♂.

TL mm 2.66. Body elongated, depigmented, yellow-testaceous; integument shiny, with evident microsculpture, covered with very short pubescence.

Head large, slightly wider than the base of the pronotum. Labium without tooth. Antennae short, just exceeding the base of the pronotum when stretched backwards. Fronto-clypeal furrow of frontal clypeo slightly distinct; anterior margin of the epistome subrectilinear.

Pronotum elongated (max. width / max. length ratio = 0.90), maximum width at the middle, basal border slightly narrower than the anterior border, pronotum sides poorly arcuate, distinctly crenelated at the posterior fourth, emarginated before the base. Anterior angles rounded, not prominent; posterior angles sharp, squared, not protruding. Disc slightly convex, with very sparse and short pubescence; median groove very shallow, slightly marked. Marginal groove wide and flat, enlarged near the base; anterior marginal setae inserted inside the marginal groove, approximately on the anterior fifth; basal setae inserted before the posterior angles.

Legs long and slender, with metatrochanters normal and metafemora (Fig. 50 ) armed with a long, internal spur; two protarsomeres dilated and without adhesive phanerae in male.

Elytra subrectangular, very elongated (max. length/max. width ratio = 2.28), with parallel sides, slightly emarginated before apex. Disc convex; integument shiny, with evident microsculpture and short, longitudinally aligned and upright pubescence. Humeri very marked, squared; post-humeral margin denticulate, with a distinct crenulation up to the 8th pore of the umbilicate series; elytral apices separately rounded. Marginal groove narrow and evident up to the 8th pore of the umbilicate series.

Chaetotaxy: scutellar pore large, foveate. Umbilicate series with 1st, 2nd, and 3rd pores of the humeral group almost equidistant; 4th pore clearly farther from the 3rd one and placed at the end of the basal third of the elytron; 5th pore placed at the end of median third of the elytron; 5th and 6th pores spaced out ca. 1/4 of the distance from 6th and 7th pores; 7th, 8th, and 9th pores not displaced onto the disc and not equidistant, 8th pore placed after the 9th one. One single discal seta in the central area of the disc and placed approximately at the level of the 9th pore.

Aedeagus (Fig. 51 ) relatively large, median lobe, in lateral view, long and restricted at apex, regularly curved and not restricted before the basal bulb, basal bulb of normal size. Ventral margin curved from basal bulb to apex, gently emarginated just before the apex; apical blade evident, but short. Endophallus without sclerified phanerae. Parameres relatively long and robust, bearing two setae: one apical and one subapical; right paramere shorter than the left one.

Etymology.

The name comes from the Latin word armato (which means armed) to highlight the presence of a large spur on metafemora.

Distribution.

Angustanillus armatus sp. nov. is known only from the type locality Mesa B, 38 km W of Pannawonica, Pilbara, WA.

Figures

Figures 49 - 51. Angustanillus armatus sp. nov., HT ♂ 49 habitus 50 left metafemur and metatrochanter in dorsal view 51 aedeagus in lateral view. Scale bars: 0.1 mm.