About the Chocolate Mining Bee
Andrena trimmerana, Trimmer's mining bee, is a species of mining bee from the family Andrenidae. It occurs in the western Palearctic but its true status in some areas is muddled due to issues of taxonomy and misidentification.
Andrena trimmerana is bivoltine and the broods differ from each other in morphology, especially the male bees. They are difficult to separate from the closely related and partially sympatric A. scotica. The females of A. trimmerana can be separated from females of A. scotica by the red patches of colour on the sides of tergite 1 and the reddish colour of the basal sternites. This reddish colour on the basal sternites is similar to A. bimaculata but A. trimmerana is larger and is rougher on the top of the propodeum. The later, summer generation of A. rosae also resembles A. trimmerana but it has shorter hairs all over its body. They measure 13-15mm in length.
The early brood or spring generation males possess a spine on their genae which is of variable size, this is also present in the males of the spring generation of A. rosae but they have an all dark abdomen and lack an apical tooth on their mandibles, while the males of A. ferox also have... Wikipedia →