Brachyusa saskatchewanae Klimaszewski & Larson

Klimaszewski, Jan, Larson, David J., Labrecque, Myriam & Bourdon, Caroline, 2016, Twelve new species and fifty-three new provincial distribution records of Aleocharinae rove beetles of Saskatchewan, Canada (Coleoptera, Staphylinidae), ZooKeys 610, pp. 45-112 : 91-92

Taxon classification Animalia Coleoptera Staphylinidae

Brachyusa saskatchewanae Klimaszewski & Larson sp. n. Figs 99-105

Holotype (male).

Canada, Saskatchewan, Bear Creek at Crane Lake, near Piapot, 18-VIII-2011, D. Larson (LFC). Paratypes. Canada, Saskatchewan, Grasslands National Park, Frenchman River at Ecotour Rd., 26-VII-2004, sandy-clay river bank, D. Larson (DLC) 1 male; Bigstick Lake, 16 km E Golden Prairie, 21-IX-2011, D. Larson (DLC, LFC) 4 females.

Etymology.

The name of this species, saskatchewanae -, is a feminine adjective derived from the name of the province of Saskatchewan, where the type series was found.

Diagnosis.

Body narrowly oval, length 2.3-2.5 mm, slightly flattened; uniformly black with light brown tarsi (Fig. 99); integument moderately glossy with short and silky pubescence (Fig. 99); antenna with articles I-VII elongate, VIII-IX subquadrate to slightly transverse (Fig. 99); head distinctly narrower than elytra and with large eyes, postocular region very short and abruptly narrowed basally (Fig. 99); pronotum wider than head but narrower than elytra, sinuate baso-laterally and strongly converging apically in apical third, pubescence directed straight and obliquely posteriad (Fig. 99); elytra at suture about as long as pronotum, pubescence directed straight posteriad, basal margin concave (Fig. 99); abdomen strongly narrowed posteriad, three basal tergites with deep transverse impressions (Fig. 99); metatarsus with basal article less than twice as long as second (Fig. 99). MALE. Tergite VIII transverse with broad apical emargination (Fig. 101); sternite VIII strongly elongate, with wide space between base of disc and antecostal suture, apical margin rounded (Fig. 102); median lobe of aedeagus with very long and narrow tubus in lateral view, bulbus large with large crista apicalis (Fig. 100). FEMALE. Tergite VIII slightly triangularly produced at apex (Fig. 103); sternite VIII with shallow apical emargination (Fig. 104); spermatheca L-shaped, with sac-shaped capsule angularly connected to club-shaped stem (Fig. 105).

Brachyusa saskatchewanae may be distinguished from other Brachyusa species by its uniformly black and narrow body, sinuate lateral margins of pronotum, and the genitalic features described above (Figs 99, 100, 105).

Distribution.

Known only from SK.

Natural history.

All SK specimens were captured near water with some on sandy-clay river bank. They were mainly collected by splashing water onto the bank, which caused the beetles to run up the bank.