Megachile sculpturalis

Females are large, 22 to 27 mm long, while males are smaller at 14 to 19 mm.

The body is typically black and yellow-brown, with a dark head bearing yellow-brown hairs and smoky wings with dark marks near the edges.

The species is native to China, Japan and a few other places in eastern Asia.

It was first collected in North America in North Carolina in 1994 and then spread rapidly, reaching Alabama by 1999 and Canada by 2002.

Later records extended its known US range southwest through Arkansas, Louisiana, Mississippi, Missouri and Texas.

In Europe it was first found in 2008 near Marseille in France, most likely arriving by ship, and by 2020 there were many records from Switzerland, Liechtenstein and Austria.

Each brood cell receives a ball of pollen and resin, a female can build as many as 10 cells per nest, and larvae pupate in spring with adults emerging in early summer.

In Europe the flight season starts in late June to early July and generally ends in mid-September.

Females prefer to nest in existing cavities because they cannot bore their own holes in wood, and they will occupy abandoned nests of similar-sized bees.

In Europe females use existing holes in dead wood or reed; the cavity walls and entrance are sealed with resin and the partitions between cells are covered with a layer of mud.

The bee is polylectic, with 43 plant species in 21 families recorded as floral hosts.

It shows a preference for pollen of the Japanese pagoda tree, Sophora (Styphnolobium) japonica.

Females have been seen aggressively evicting carpenter bee females from their nest tunnels in order to nest there themselves.

Females can sting but are not aggressive and usually fly away from people; the species is thought to have travelled along maritime trade routes as a stowaway.