Atheta (Microdota) riparia Klimaszewski & Godin

Klimaszewski, Jan, Godin, Benoit & Bourdon, Caroline, 2012, Further contributions to the aleocharine fauna of the Yukon Territory, Canada (Coleoptera, Staphylinidae), ZooKeys 186, pp. 207-237 : 213

Atheta (Microdota) riparia Klimaszewski & Godin sp. n. Figs 824, 2548-51

Holotype

(male). Canada, Yukon, Whitehorse, Paddy’s Pond, 60.7067, -135.0917, 16.IX.2007, 649 m, litter sifting, mixed aspen and white spruce forest, B. Godin (LFC).

Paratype.

Same data as the holotype (ECW) 1 male.

Non-type.

Canada, Yukon, Watson Lake, Watson Creek, 60.12723, -128.8053, 16.VIII.2007, 697 m, mushrooms, B. Godin (LFC) 1 female.

Etymology.

The name of this species derives from the Latin adjective riparius, -a, -um,in allusion to the wet litter where the types were found.

Diagnosis.

Body small and narrow, subparallel; black, with tarsi reddish-brown; moderately glossy, with fine, dense punctation and meshed microsculpture on forebody (Fig. 8); head approximately as wide as pronotum, depressed medially, eyes slightly protruding; antennae slender, slightly incrassate apicad, articles 4-10 slightly to strongly transverse; pronotum emarginate laterally; elytra broader and longer at suture than pronotum; head, pronotum and base of abdomen of the same width; sides of abdomen subparallel; length 1.9-2.0 mm (Fig. 8). MALE: tergite 8 truncate apically and with smooth margin (Fig. 48); sternite 8 widely rounded apically (Fig. 49); median lobe of aedeagus with apex narrow and ventrally produced (Fig. 24). FEMALE (non-paratype): tergite 8 truncate apically (Fig. 50); sternite 8 broadly rounded apically (Fig. 51); spermatheca slightly distorted but with club-shaped capsule and posteriorly-twisted stem (Fig. 25).

This species differs from other Nearctic Microdota by the combination of body shape, strongly punctate surface and the shape of the median lobe of the aedeagus and spermatheca.

Distribution. This native Nearctic species is known only from the Yukon Territory but it is probably more widely distributed in northern Canada.

Bionomics. The two males were captured in September in wet, organic litter and the female was found in mushrooms in mid-August.