Hydrosmecta minutissimoides Webster and Klimaszewski, 2017

Klimaszewski, Jan, Webster, Reginald P. & Davies, Anthony, 2017, Genus Hydrosmecta C. G. Thomson: a review of species occurring in eastern Canada (Coleoptera, Staphylinidae, Aleocharinae), Insecta Mundi 2017 (593), pp. 1-17 : 8

Hydrosmecta minutissimoides Webster and Klimaszewski , new species

( Fig. 32–38 )

Holotype (male): Canada, New Brunswick, Queens Co., Bayard, at Nerepis River , 45.4426°N, 66.3280°W, 25.V.2008, R. P. Webster // river margin, in moist gravel ( CNCI) . Paratype (female): Canada, New Brunswick, New Maryland, Charters Settlement, 45.8395°N, 66.7391°W, 20. VII.2006, R.P. Webster // mixed forest, MV light ( RWC).

Etymology. The species name minutissimoides is derived from a Latin adjective meaning ‘the smallest’, referring to the fact that this is the smallest species of Hydrosmecta .

Diagnosis. Body length 1.5–1.6 mm; subparallel, flattened, light brown with head and abdomen dark brown, legs and basal antennomeres yellow ( Fig. 32 ); moderately glossy, with fine and dense punctation and pubescence; faint meshed microsculpture present on forebody; head large, as wide as pronotum, postocular area about twice as long as eye in dorsal view, posterior angles rounded; eyes moderately large; antennae moderately long, reaching two-thirds of length of elytra, antennomeres I–II distinctly elongate, III moderately elongate, IV subquadrate, V–X slightly transverse, XI clearly shorter than two preceding antennomeres combined; pronotum transverse, widest in apical third, as wide as head and elytra, slightly depressed medially; elytra elongate and flattened, at suture about one-fourth longer than pronotum; abdomen subparallel, slightly narrowed apically. Male: tergite VIII broadly truncate apically ( Fig. 34 ); sternite VIII longer than wide, with apical margin truncate in middle third, rounded laterally, antecostal suture widely separated from basal margin ( Fig. 35 ); median lobe of aedeagus with large bulbus, tubus strongly narrowly produced, triangular, arcuate ventrally in lateral view ( Fig. 33 ). Female: tergite VIII slightly, very broadly emarginate apically ( Fig. 36 ); sternite VIII with apical margin broadly truncate, laterally rounded ( Fig. 37 ); spermatheca S-shaped, capsule short, spherical, with large apical invagination, stem sinuate and broadly looped and twisted posteriorly ( Fig. 38 ).

Distribution. Origin: Nearctic. Canada: NB. USA: not recorded.

Collection and habitat data. Habitat: One specimen collected at MV light in a mixed forest; the other was found in moist gravel on a river margin ( Fig. 48 ). Collecting period: V, VII. Collecting method: examining moist gravel and collecting at a MV light.

Figures

Figure 48. Gravel bar habitat at Nerepis River, Queens Co., Bayard, NB, habitat for Hydrosmecta caduca Casey, H. canadensis Webster and Klimaszewski, sp. nov. (type locality),H. dulcis Casey, andH. minutissimoides Webster and Klimaszewski, sp. nov. (type locality).

Figures 32–38. Hydrosmecta minutissimoides Webster and Klimaszewski, sp. nov.32) Habitus in dorsal view.33) Median lobe of aedeagus in lateral view. 34) Male tergite VIII. 35) Male sternite VIII. 36) Female tergite VIII. 37) Female sternite VIII. 38) Spermatheca. Scale line for habitus = 1 mm, remaining scale bars = 0.2 mm.