Trichiusa pilosa Casey

Klimaszewski, Jan, Godin, Benoit, Langor, David, Bourdon, Caroline, Lee, Seung-Il & Horwood, Denise, 2015, New distribution records for Canadian Aleocharinae (Coleoptera, Staphylinidae), and new synonymies for Trichiusa, ZooKeys 498, pp. 51-91 : 70-73

Taxon classification Animalia Coleoptera Staphylinidae

Trichiusa pilosa Casey Figs 16-23

Trichiusa pilosa Casey 1894: 341, 343; Moore and Legner 1975: 504. LECTOTYPE (female): USA: RI [Rhode Island; in orig. descrip. Boston Neck]; Casey determ. pilosa -3; Casey bequest 1925; Trichiusa pilosa Casey, Gusarov V.I. det. 2010; our lectotype designation label, present designation (USNM). PARALECTOTYPES: labelled as the lectotype except: Casey determ. pilosa -4(USNM)1 male; Casey determ. pilosa -5(USNM)1 female; Type USNM 39424(USNM)1 male.

Trichiusa atra Casey 1906: 330; Moore and Legner 1975: 504. New Synonymy. LECTOTYPE (male): USA: McPherson, W. Kansas; atra Casey; Type USNM 39426; Casey bequest 1925; Lectotypus Trichiusa atra Casey, Gusarov V.I. det. 2011 [unpublished designation]; our lectotype designation label, present designation (USNM).

Trichiusa monticola Casey 1906: 328; Moore and Legner 1975: 504. New Synonymy. LECTOTYPE (male): USA: Coeur d’Alene, Idaho [in orig. descrip. H.F. Wickham]; monticola Casey; Type USNM 39421; Lectotypus Trichiusa monticola Casey, Gusarov, V.I. des. 2011[unpublished designation]; our lectotype designation label, present designation (USNM).

Trichiusa parviceps Casey 1906: 328; Moore and Legner 1975: 504. New Synonymy. LECTOTYPE (female): USA: Cin. [in orig. descript.: Ohio, Cincinnati, Chas. Dury]; parviceps Casey; Casey bequest 1925; Lectotypus Trichiusa parviceps , Gusarov V.I. des. 2011 [unpublished designation]; our lectotype designation label, present designation (USNM).

Trichiusa postica Casey 1906: 330; Moore and Legner 1975: 504. New synonymy. LECTOTYPE (male): W.H.H. [W.H. Harrington], Ottawa, Canada; Type USNM 39427; Casey bequest 1925; Trichiusa pilosa Casey, Gusarov, V.I. det. 2010; our lectotype designation label, present designation (USNM).

Diagnosis.

Body broadly oval (Fig. 16), length 1.5-1.8 mm, dark brown with reddish tinge and slightly paler base of abdomen or uniformly black, appendages usually lighter than rest of body (Fig. 16); sparsely punctate and pubescent; setae straight and erect, particularly on pronotum; integument strongly glossy; head slightly narrower than pronotum; pronotum moderately transverse, rounded laterally and basally, distinctly narrower than elytra; elytra broad at suture about as long as pronotum; abdomen arcuate laterally and broadest at middle of its length. MALE. Median lobe of aedeagus with oval bulbus and triangularly shaped tubus in dorsal view (Fig. 18), in lateral view tubus slightly sinuate and narrow apically with apex narrowly rounded (Fig. 17); internal sac structures not pronounced; tergite VIII short and truncate apically (Fig. 19); sternite VIII slightly produced apically and rounded at apex and with narrow distance between base of disc and antecostal suture (Fig. 20). FEMALE. Tergite VIII short and truncate apically (Fig. 22); sternite VIII broadly arcuate apically (Fig. 23); spermatheca with broad and sac-shaped capsule with minute apical invagination, stem narrow, sinuate and narrowly twisted apically (Fig. 21).

Distribution.

Natural history.

In Alberta, one female was collected using a window trap deployed in a 10-year-old regenerating white spruce stand. The British Columbia specimens were found on bison scat. The adults were collected from June to September.

Comments.

The two specimens from British Columbia agree with the type series in external morphology and shape of genitalia except for the entirely black body. It is well known that many aleocharine species exhibit darker colour at higher latitudes compared with more southern populations.