Lemon cuckoo bumble bee

Lemon cuckoo bumble bee is a common, small, cuckoo bumble bee. The female has a black spot on the thorax and an entirely black abdomen. The male also has a black spot on the thorax but the first three abdominal segments are yellow.

The female (worker) bee is ⅝″ to 13 ⁄16″ in total length and ¼″ to ⅜″ wide at the abdomen. The head is covered with copious long, erect, black hairs. In the area between the large compound eyes (vertex) these are interspersed with short yellowish hairs. The hairs on the back of the head are yellow. The space between the lateral simple eyes (ocelli) and the margin of the vertex is two times that between the ocelli and the compound eyes. The first and third antennal segments are considerably longer than the second, which is slightly shorter than wide. The thorax is covered with dense, copious, yellow hairs except for a black spot in the center. The black spot is more or less bare and does not reach the base of the wings. The abdomen is entirely black, and is densely covered with short, erect, black hairs. The legs are mostly covered with black hairs except for pale hairs on the last foot (tarsal) segments, which have pale hairs. There is no pollen basket (corbicula).

The male bee is smaller, ½″ to ⅝″ in total length and 3 ⁄16″ to ½″ wide at the abdomen. The first three segments of the abdomen are yellow, covered with dense, erect, yellow hairs.

Male: ½″ to ⅝″

Female: ⅝″ to 13 ⁄16″

May to October

The lemon cuckoo bumble bee has no pollen baskets and does not collect pollen. It invades the nests of mostly common eastern bumble bee but also half-black bumble bee and two-spotted bumble bee. It kills the queen and usurps the colony and its worker bees.

Larvae are fed both nectar for carbohydrates and pollen for protein.

Adults feed mostly on nectar but also on some pollen.