Bombus citrinus

Bombus citrinus

Bombus (Psithyrus) citrinus (the lemon cuckoo bumble bee)

Status in Illinois

Rare.

Technical description (from Medler and Carney 1963)

Queen: Face and vertex with hairs entirely black. Dorsum of thorax mostly with yellow hairs, but interalar area and scutellum bearing an admixture of yellow and black hairs; pleura yellow above, but with black hairs below. Abdominal tergites 1 and 2 black, hind corner of tergite 3, all of tergite 4, and sides of tergite 5 clothed with yellow-white hairs. Venter of abdomen with a sprinkling of yellow hairs, legs largely with black hairs.
Male: Face with black hairs, vertex with yellow hairs. Dorsum of thorax covered with yellow hairs except for a scattering of black hairs in the interalar area which results in a poorly defined black band; pleura largely yellow, but black hairs at bases of the legs. Abdominal tergite 1 all yellow, tergite 3 yellow at the sides, 4 and 5 mostly yellow, and 6 with yellow hairs at the sides; remainder of the tergites with black hairs. Venter of abdomen with fringes of yellow hairs, legs largely black.

Diagnosis

Habits

Flight periods

Queens: . Males: .

Main flower preferences

Host species

Among Bombus species that occur in Illinois, B. (P.) citrinus is known to parasitize B. impatiens and B. vagans.

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