Orthoperus corticalis (Redtenbacher, 1845)

Pentinsaari, Mikko, Anderson, Robert, Borowiec, Lech, Bouchard, Patrice, Brunke, Adam, Douglas, Hume, Smith, Andrew B. T. & Hebert, Paul D. N., 2019, DNA barcodes reveal 63 overlooked species of Canadian beetles (Insecta, Coleoptera), ZooKeys 894, pp. 53-150 : 53

Orthoperus corticalis (Redtenbacher, 1845) Figure 36

Distribution.

Native to the Palaearctic region. Widely distributed from Western Europe to Siberia ( Bowestead 1999, 2007). Adventive in the Nearctic region (Ontario, Canada).

Canadian records.

Ontario: Cambridge, 29-Apr-2015 to 07-May-2015 (1 ex, CBG); Cambridge, 07-May-2015 to 14-May-2015 (1 ex, CBG); Cambridge, 21-May-2015 to 27-May-2015 (1 ex, CBG).

Diagnostic information

(based on Bowestead 1999). Body length 0.8-1.0 mm. Habitus slightly elongate oval, strongly convex ( Fig. 36A ). Dark brown to black, antennal base and legs pale, five apical antennomeres dark brown. Pronotum finely punctate, often with a transverse row of larger punctures medioposteriorly, with isodiametric microsculpture throughout. Elytral punctation fine, punctures larger basally, interspaces with similar microsculpture as the pronotum, the microsculpture forming wavy transverse rows of cells especially basally. Sutural striae of elytra present only at the apex. Male metaventrite with an elongate depression medially, and a short median keel behind the depression, distance of the keel from hind edge of metaventrite ca. 1/12 of the length of the metaventrite ( Fig. 36B ). Aedeagus as in Fig. 36C, D .

Bionomic notes.

This species is mainly known from deciduous forests. It has been collected from a variety of fungus species growing on dead logs, and under the bark of fungus-infested logs ( Bowestead 1999, Rutanen 2015). The Canadian specimens were collected with a Malaise trap at the edge of a forest.

Comments.

This is the second species of Orthoperus recorded as adventive in Canada: the Palaearctic O. atomus (Gyllenhal, 1808) is known from British Columbia in Canada, and Washington and Oregon in the United States ( Klimaszewski et al. 2015). Orthoperus corticalis is darker and slightly larger than O. atomus , with stronger punctation on the pronotum and elytral base and denser and more strongly impressed microsculpture ( Bowestead 1999). Two native North American species are currently known from Canada: O. scutellaris LeConte, 1878 has small V-shaped scratches on the elytra instead of punctures, and O. suturalis LeConte, 1878 has fine but distinctly impressed sutural striae (only faintly visible close to the elytral apex in O. corticalis ) ( LeConte 1878, Downie and Arnett 1996).

Figures

Figures 36, 37. 36 Orthoperus corticalis (Redtenbacher) 36 A habitus, L. Borowiec 36 B male metaventrite 36 C aedeagus, ventral view 36 D aedeagus, lateral view 37 Litargus connexus (Geoffroy) 37 A habitus, L. Borowiec 37 B antenna. Scale bars: 0.25 mm (36 A), 0.2 mm (36 B-D), 0.5 mm (37 A), 0.2 mm (37 B).