Atheta (Dimetrota) mcalpinei Klimaszewski & Webster

Webster, Reginald P., Klimaszewski, Jan, Bourdon, Caroline, Sweeney, Jon D., Hughes, Cory C. & Labrecque, Myriam, 2016, Further contributions to the Aleocharinae (Coleoptera, Staphylinidae) fauna of New Brunswick and Canada including descriptions of 27 new species, ZooKeys 573, pp. 85-216 : 112-115

Taxon classification Animalia Coleoptera Staphylinidae

Atheta (Dimetrota) mcalpinei Klimaszewski & Webster sp. n. Figs 128-132

Holotype (male).

Canada, New Brunswick, Northumberland Co., ca. 2.5 km W of Sevogle, 47.0876°N, 65.8613°W, 27.VIII.2013, R.P. Webster // Old jack pine forest, in rotting gilled mushroom (LFC). Paratype. New Brunswick, Northumberland Co., ca. 2.5 km W of Sevogle, 47.0876°N, 65.8613°W, 27.VIII.2013, R.P. Webster // Old jack pine forest, in rotting gilled mushroom (1 ♂, RWC).

Etymology.

Named for Dr. Donald McAlpine, Curator and Head, Zoology Section of the New Brunswick Museum in recognition of his work studying and promoting research on the invertebrate and vertebrate fauna of NB.

Description.

Body length 2.9-3.0 mm, broadest at elytra; head, pronotum, and abdomen dark brown to nearly black, elytra yellowish brown mottled with dark brown, legs, bases of antennae, and maxillary palps yellowish brown (Fig. 128); integument moderately glossy with meshed microsculpture; forebody with fine and sparse punctation and pubescence except denser on elytra; head rounded and arcuate posterolaterally, with large eyes, each about as long as postocular area; antennae with articles V–X subquadrate to strongly transverse; pronotum transverse, rounded on sides, slightly wider than head and distinctly narrower than elytra, pubescence directed laterad from midline of disk; elytra transverse, with pubescence directed posterolaterad and forming waves posteriorly; abdomen gradually narrowed posteriad, narrower than elytra and arcuate laterally. Male. Median lobe of aedeagus with bulbus broad, narrowly oval, streamlined, tubus broad, triangular in dorsal view (Fig. 129), and slightly produced ventrally at apex, with apical part narrowly elongate in lateral view, venter approximately straight (Fig. 130); internal sac with distinct complex structures (Figs 129, 130); tergite VIII emarginate apically with sinuate margin and with two angular lateral processes (Fig. 131); sternite VIII elongate and rounded apically (Fig. 132). Female. Unknown.

Distribution.

Known only from NB, Canada.

Natural history.

Specimens were collected from rotting gilled mushrooms in a jack pine forest.

Comments.

This species bears some general resemblance to Atheta remulsa Casey from which it differs by less transverse antennal articles VII-X, darker elytra (Fig. 128), differently shaped median lobe of aedeagus with tubus straight and apex not strongly oriented ventrally (Fig. 130). For illustrations of Atheta remulsa , see Klimaszewski et al. (2011).