Angustanillus Baehr & Main, 2016

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 Baehr & Main, 2016 Figs 49-51

Type species.

Angustanillus striatipennis Baehr & Main, 2016

Diagnosis.

Included species strongly characterised by: body very elongated, posterior supraorbital seta and longitudinal elytral grooves absent, pronotum with basal border narrower than anterior border, and sides posteriorly distinctly crenelated, basal seta of pronotum present, one or two elytral discal seta present, 8th pore of the umbilicate series located after the 9th pore (sensu Giachino and Vailati 2011), metafemora dentate in males (state unknown in females), labial tooth absent, median lobe of the aedeagus long, slender and curved, parameres long and slender.

Note.

Describing Angustanillus Baehr and Main (2016) mention the presence of two setae on the elytral disc, one located in the fifth basal section, and one in the fourth apical section. The species we describe here has only one seta, situated in the posterior one. Considering the taxonomic importance of the number of setae in establishing the systematics of a taxon in Anillini ( Giachino 2005; Giachno and Vailati 2011), together with the difficulties in identifying these setae without a proper preparation and observation with a microscope at high magnification, we consider the presence of one seta as the most probable character in this genus. However, in the genus diagnosis we account for the possible presence of one or two discal setae.

Additionally, in the genus diagnosis we indicate the presence of a large metafemoral tooth, at least in the male. The female of A. armatus sp. nov. is unknown to date, and the female holotype is known only for A. striatipennis Baehr and Main (2016), therefore still it is not possible to confirm the presence of this character state in both sexes of the two species. We hence re-describe the genus Angustanillus integrating the new characters presented by A. armatus sp. nov.

Redescription.

Included large size species (TL> mm 2.40), anophthalmous. Depigmented and sclerified integument, with strong microsculpture (sometimes formed by distinct, deep, large punctures) and covered with dense pubescence.

Head wider than the pronotum base; mandibles short and simple, without hyperplasias. Maxillary palps ovoidal, swollen. Labium transverse, articulated; mentum not fused with submentum. Labial tooth absent. Antennae not strictly moniliform (with relatively elongated antennomeres).

Pronotum elongated, with sides distinctly crenelated in the basal fourth, not sinuate in the basal third. Pronotum basal border slightly narrower than the anterior border; basal angles sharp and squared; basal seta present, placed before basal angles.

Elytra subrectangular and elongated, separately rounded, not or distinctly emarginated apically; convex, without longitudinal grooves. Elytral striae present (4 striae) or missing (except for the sutural stria). Lateral margin, starting from the humeral area, hardly serrulate up to the level of 8th pore of the umbilicate series.

Scutellar pore present, large and umbilicate; umbilicate series of type B (sensu Jeannel 1963; Giachino and Vailati 2011), 8th pore placed after the 9th pore; disc bearing one (posterior) or two setae in the central area of the disc.

Legs relatively long and slender. Male metafemora distally armed with a long, internal spur; metatrochanters normal; two protarsomeres dilated and without adhesive phanerae in males.

Aedeagus relatively large; median lobe long, curved, not restricted before the basal bulb that is of normal size. Parameres relatively long and robust, bearing two setae: one apical and one subapical. Endophallus without sclerified phanerae.

Species included.

The following two species belong to this genus:

Angustanillus striatipennis Baehr & Main, 2016

Angustanillus armatus sp. nov.

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.