Myllaena infuscata Kraatz, 1853

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

Myllaena infuscata Kraatz, 1853 Figure 8

Distribution.

Native to the western Palaearctic region, widely distributed in Europe but rare in the north ( Palm 1968) and also reported from India (Kashmir) ( Schülke and Smetana 2015), though many of these records need confirmation ( Assing 2018). It has previously been reported as occurring in the Nearctic region by Schülke and Smetana (2015) but this is probably based on an erroneous synonymy of North American M. immunda Casey with this species in older literature. Klimaszewski (1982) corrected the synonymy, and M. immunda is now considered a synonym of M. arcana Casey, 1911. The true M. infuscata is reported here as adventive in the Nearctic region (Ontario, Canada).

Canadian records.

Ontario: Rouge National Urban Park, 15-Sep-2013 (1 ex, CBG).

Diagnostic information.

Body length 1.2-1.5 mm. Habitus as in Fig. 8A . Aedeagus as in Fig. 8B, C . Spermatheca as in Fig. 8D .

Bionomic notes.

Myllaena infuscata occurs in both exposed and shaded microhabitats along the margins of still and running water ( Reid 1991). The Canadian specimen was extracted from soil and leaf litter collected near the mouth of Rouge River.

Comments.

Myllaena infuscata is distinctive in the Nearctic fauna for its spermathecal shape, which forms concentric circular coils ( Fig. 8D ). The median lobe of the aedeagus in lateral view is also distinctive among species in North America ( Fig. 8B, C ). Within the western Palaearctic fauna, only M. minuta has similar genitalia but differs in the shape of the median lobe in lateral view. The single female from Ontario bears the characteristic spermatheca and its corresponding barcode sequence falls within the BIN associated with M. infuscata , rather than M. minuta , its similar sister species. It is unknown whether this is a recent introduction to North America or if its small size has impeded its detection.

Figures

Figures 7, 8. 7 A Atheta vaga (Heer), habitus 7 B Atheta vaga, aedeagus, lateral view 7 C Atheta fanatica Casey, aedeagus, lateral view 7 D Atheta fanatica, spermatheca 8 Myllaena infuscata Kraatz 8 A habitus 8 B aedeagus, ventral view 8 C aedeagus, lateral view 8 D spermatheca 8 B-D V. Assing. Scale bars: 1.0 mm (7 A), 0.2 mm (7 B-D), 0.5 mm (8 A), 0.1 mm (8 B-D).