Atheta (Hydrosmectomorpha) newfoundlandica (Klimaszewski and Langor)

Klimaszewski, Jan, Webster, Reginald P., Davies, Anthony & Bourdon, Caroline, 2018, Description of Hydrosmectomorpha Klimaszewski and Webster, a new subgenus of Atheta C. G. Thomson, with three new Canadian species (Coleoptera: Staphylinidae: Aleocharinae), Insecta Mundi 648, pp. 1-12 : 4

Atheta (Hydrosmectomorpha) newfoundlandica (Klimaszewski and Langor)

( Fig. 8–15 )

Hydrosmecta newfoundlandica Klimaszewski and Langor, in Klimaszewski et al. 2011. Webster et al. 2012, Klimaszewski et al. (in press).

Diagnosis. Body subparallel, flattened ( Fig. 8 ), length 2.8–3.4 mm; colour dark brown with antennae, legs and elytra paler, reddish- or yellowish-brown ( Fig. 8 ); integument moderately glossy, forebody with fine, moderately dense punctation and faint meshed microsculpture; head slightly narrower than pronotum, eyes large but not protruding ( Fig. 8 ); antennae moderately robust, all antennomeres slightly to distinctly elongate ( Fig. 8 ); pronotum widest at apical third (0.52 mm) ( Fig. 8 ); elytra flattened, dis- tinctly elongate, at suture about as long as pronotum, broader than pronotum (0.61 mm at shoulders) ( Fig. 8 ); abdomen subparallel, slightly widening apicad. Male. Apical margin of tergite VIII sinuate with two small lateral denticles, and variable number of minute denticles near middle ( Fig. 11 ); sternite VIII deeply emarginate basally and parabolically rounded from base to apex ( Fig. 12 ); median lobe of aedeagus in lateral view with tubus wide, ventral margin straight, apex abruptly bent ventrad ( Fig. 9 ); in dorsal view bulbus large, ovoid, tubus broad, moderately long, triangular apically ( Fig.10 ). Female. Apical margin of tergite VIII with broad, shallow emargination medially ( Fig. 13 ); sternite VIII broadly rounded apically ( Fig. 14 ); spermatheca short, capsule broad, tubular and elbowed, apical invagination wide and deep, stem highly sinuate ( Fig. 15 ).

Distribution. Origin: Nearctic. CANADA: NF, NB. USA: TN.

New record from Tennessee: USA, Tennessee, Fentress Co., Fallen Entrance Cave, 4 mi SSW Jamestown , 26.IX.03, J. Lewis ( LFC) 1 female .

Habitat and collection data. Habitat. NB specimens were collected from among cobblestones along clear, rocky, river margins near the outflow of brooks. One individual was collected from the margin of a spring-fed brook among gravel on firm sand/clay/gravel mix near the outflow of the brook into a clear, rocky river. Others were collected on a partially shaded cobblestone island in a clear, fast flowing river. Specimens were usually found among cobblestones and gravel at water’s edge. Klimaszewski et al. (2011) did not specify the habitat of NF specimens. Collecting period. V-VIII. Collecting method. Hand collecting from among cobblestones near water.

Comments. Externally, A. newfoundlandica somewhat superficially agrees with some characteristics of the genus Hydrosmecta , within which it was originally classified ( Klimaszewski et al. 2011), but it has the median lobe of the aedeagus and the spermatheca of the Atheta type.

Figures

Figures 8–15. Atheta (H.) newfoundlandica (Klimaszewski and Langor). 8) Habitus in dorsal view. 9) Median lobe of aedeagus in lateral view. 10) Median lobe of aedeagus in dorsal view. 11) Male tergite VIII. 12) Male sternite VIII. 13) Female tergite VIII. 14) Female sternite VIII. 15) Spermatheca. Scale line for habitus = 1 mm, remaining scale lines = 0.2 mm. Arrows indicate important diagnostic features.