Leafcutter Bees - Megachile

A genus of bulky looking bees, all of which make nest chambers for their young using bits of leaf cut from plants. Roses are a particular favourite, and a rose bush with semicircular pieces missing from the edges of its leaves is a good sign that one of these bees is around. The pollen basket is carried on the underside of the abdomen, and the pattern of colour is a key identification characteristic. Males lack the pollen basket, and can be very difficult to identify. Three species (maritima, willughbiella and circumcincta) have distinctive expanded front tarsi which help distinguish them from the other species. There are 7 extant UK species.

Megachile ligniseca - large, dark, uncommon species. Females with tricolored scopae and adpressed black hair on tergite 6. Males with normal fore basitarsi

Megachile centuncularis Common and widespread species, females with all red scopae, males indistinguishable in the field from versicolor. Small

Megachile versicolor - Small species, common and widespread. Females have red scopae with black tip and adpressed black hairs on tergite 6. Males indistinguishable from centuncularis in the field.

Megachile willughbiella - Common and widespread large species. Females with red scopae black at tip and erect black hairs on tergite 6. Males have expanded fore basitarsi with hair fringe at least as broad as basitarsi

Megachile maritima - Large species found on coasts and inland heaths. Females have tricoloured scopae and erect black hairs on tergite 6, as well as long hairs on the fore basitarsi. Males have fore basitarsi expanded, hair fringe no more than half thickness of basitarsi, flattened final antennal segment and diagnostic circular incision in rear of fore tibia where it joins the tarsus.

Megachile leachella - Large species with restricted coastal distribution. Females silvery-white, with diagnostic pair of silver spots on last tergite. Males with normal fore basitarsi and distinctive green eyes.

Megachile circumcincta - Widespread but scarce coastal species. Erect black hairs on tergite 6 and no terminal bands on tergites 4 and 5. Sides of face with brownish or brownish-black hairs