Andrena nigrospina Thomson,1872
Description and notes
This species is the rarer of the two formerly known as A. pilipes or A. carbonaria. It has a single flight period which occurs in May and June between the two broods of A. pilipes sens. str. Andrena nigrospina has shown a very marked decline in distribution since the mid 20th century, although quantifying this is very difficult as many of the records do not now have specimens to back them up and so cannot be re-examined. Examination of male genitalia is necessary for determination, and specimens flying in June are thought most likely to be this species,
Distribution
Central and southern England, with modern records coming from Surrey, Staffordshire and Worcestershire.
It is widely distributed in Central Europe.
Status (in Britain only)
As the split in the two species post-dates both the Red Data Book (Shirt, 1987) and the Review (Falk, 1991) this species is not currently listed. It is clear, however, that its status should be reviewed.
Habitat
There is possibly some association with sandy areas.
Flight period
May to June.
Pollen collected
Chambers (1968) gives Brassicaceae as a pollen source, although the identification of A. nigrospina is an inference from the flight period. G Trevis (pers. comm.) has observed the bee collecting pollen and nectar from wild radish.
Nesting biology
Nests in aggregations in bare soil at the Staffordshire locality (G Trevis, pers. comm.). Elsewhere in Europe it has been reported as nesting singly.
Flowers visited
In Surrey this species has been found visiting flowers of hoary mustard, rape and groundelder (Baldock, 2008) and G Knight (pers. comm.) found males flying around flowering broom in Staffordshire.
Parasites
A very dark and structurally distinct form of what otherwise appears to be Nomada fulvicornis Fabricius has been identified as being associated with this species in the Staffordshire area (Falk, 2005).
Year profile last updated
2012