Is hortorum pratorum-sized with white tail pls?

[Dillybythesea]

I've been looking for a guide to the size of the various common bees but have failed miserably. Am I right in thinking that the pratorum-sized bees but with yellow shoulders, a bit of yellow split at the waist and white tails are B. hortorum? Like so, please?

[Matt Smith]

Originally Posted by Dillybythesea

I've been looking for a guide to the size of the various common bees but have failed miserably. Am I right in thinking that the pratorum-sized bees but with yellow shoulders, a bit of yellow split at the waist and white tails are B. hortorum? Like so, please

Unfortunately no. Bumblebee workers vary in size depending on how much food they got as larvae, the first brood of workers reared by the queen on her own can be tiny compared to later broods reared by a large number of workers.

Best way with bumbles is to look at the stripes of colour. B. hortorum has a yellow collar, yellow on the back of the thorax, yellow at the top of the abdomen and a white tail - yellow - yellow - yellow - white.

As far as I can tell from your picture and description your bee is yellow only on the collar and the top of the abdomen - this would suggest a B.lucorum or B.terrestris worker, the faint ginger stripe between the black abdomen and the white tail in B.terrestris is not apparent on very small workers.

[Dillybythesea]

Thanks Matt. It's interesting and helpful to know about the potential variation in size (I shall stop trying to find a guide!) and helpful re the bands too. I do stare at the nhm.ac diagrams, but still can't interpret. The shot I included was the only one in focus as they're on the go the whole time - but if you can bear to look at these - is there enough yellow at the back of the thorax as well as top of abdomen to make them hortorum?