This is a quick identification guide to British worker bumblebees relying mainly on hair colour. It will work, but with less accuracy, for queens and males.
The worker caste of British bumblebees can be roughly divided into three groups, white tailed, red tailed and ginger haired.
Ginger haired bumblebees illustrated below (Bombus pascuorum, B. humilis, B. muscorum, B. hypnorum, B. distinguendus.)
Bombus pascuorum - there are always some black hairs mixed with the ginger hairs on the abdomen.
Bombus humilis - all ginger except for three black hairs around the base of each wing, and there is often a darker band of ginger on the abdomen.
Bombus muscorum - the thorax is always bright ginger, there are no black hairs, the abdomen is a lighter ginger colour.
Bombus hypnorum - ginger thorax, black/ginger mixed abdomen with a white tail.
Bombus distinguendus - has a wide black band on the middle of her thorax, the rest of her hair is a light ginger.
The white tailed species illustrated (not to scale) below (Bombus lucorum, B. terrestris, B. soroeensis, B. hortorum, B. ruderatus, B. jonellus, and also Bombus hypnorum from the ginger section above.)
Bombus lucorum - the yellow tends to be lemon coloured and bright.
Bombus terrestris - the yellow tends to be orangey and can look a little dirty. Queens have a buff to light brown tail.
Bombus soroeensis - the yellow band on the abdomen is broken and curves up towards the thorax.
Bombus hortorum - has two yellow bands on the thorax.
Bombus ruderatus - also has two yellow bands on her thorax, but they tend to be more orangey than B. hortorum. This bumblebee is rare, and has been recorded in Eastern England, from Wiltshire to Gloucestershire and Cambridgeshire to Essex.
Bombus jonellus - similar to hortorum but it has a short face; B. hortorum has a long face.
Red tailed species illustrated below (Bombus pratorum, B. lapidarius, B. ruderarius, B. monticola, B. sylvarum).
Bombus pratorum - small, the yellow band on the abdomen is broken or absent.
Bombus lapidarius - all black except for the tail, the hairs fringing the pollen basket are black.
Bombus ruderarius same as B. lapidarius, but has a longer face and the hairs fringing the pollen basket are red.
Bombus monticola - two yellow bands on the thorax, most of the abdomen is red.
Bombus sylvarum - two yellow bands on the thorax, most of the abdomen is yellowish.
Related pages, Cuckoo bumblebees
North American species
N. American cuckoos
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