Red-shanked carder (Bombus ruderarius)
A small, scarce bumblebee species which appears to be declining. Confined to the south of England and Wales with the exception of a strong population on Coll and Tiree. Generally, but not always, found in association with large areas of open grassland.
Queens and workers are very similar to the common Red-tailed bumblebee (Bombus lapidarius), but have red tibial hairs around the pollen baskets, long faces, and a generally smaller and rounder abdomen. Males have greyish-yellow bands, much less bright than males of the Red-tailed bumblebee and similar to the larger Red-tailed cuckoo bumblebee (Bombus rupestris).
The banding pattern is similar to that of the Shrill carder bumblebee (Bombus sylvarum) but the yellow bands of the Red-shanked carder are much darker, almost blending with the black background (obviously straw-coloured in the Shrill carder), and the red tail of Red-shanked carders is a much brighter red than the washed-out orange of the Shrill carder bumblebee. The male genital capsule is useful to check the ID, particularly of worn specimens.
For more photos visit: https://www.flickr.com/photos/63075200@N07/sets/72157631568914765/
For more detailed information visit: http://www.bwars.com/index.php?q=bee/apidae/bombus-ruderarius