This is our largest Lasioglossum (7-10mm) and a relatively common species. Females are black in colour with pale narrow bands on the abdomen, sometimes with a slight brownish translucent hue. Males are slimmer with orange-red patches on the abdomen. It is similar to Lasioglossum albipes but the females have a rounder head, a more rugged propodeum (rear section of the thorax) and lack the greyish bloom effect on the abdomen. The males possess black mandibles rather than cream-yellow ones as seen in L. albipes. Identification is often only possible under a microscope.

Distribution in Ireland: Widespread and fairly common, although due to its similarity to other species and small size it is likely under-recorded and overlooked.

Flight period: Females can be seen from late March-late September. Males generally emerge in late June and fly until August.

Habitat: A wide variety of flowery areas with little preference, although it is less frequent in upland areas and areas over acidic soils when compared to Lasioglossum albipes. It can be common in parks, brownfield land and scrubby areas.

Flowers visited: Dandelions, hawkweeds, hawkbits, thistles, knapweeds, buttercups, willow blossom, geraniums and many other wild plants. Females are widely polylectic.

Personal records: I have recorded this species widely in Cos. Down, Antrim, Wicklow, Carlow, Armagh and Roscommon. Females are more conspicuous earlier in the year and are often found on composite flowers, whilst the males can be common in late summer, often on thistles, knapweeds and Ragwort. Nests are constructed in a wide variety of settings, such as clay and sandy banks, gravelly slopes and soft-rock cliffs, often in aggregations. It is one of the hosts of Sphecodes monilicornis and a possible host of S. ephippius.