A very distinctive bumblebee with extensive red marking over the last quarter of the abdomen and no yellow bands on the thorax of the females; males have the red tail and (usually) extensive yellow markings on the face and thorax. Confusion with the much rarer B. ruderarius is possible as the basic colour pattern is similar. However, the abdomen of the female B. ruderarius is approximately circular in outline, whilst that of B. lapidarius is distinctly elongate. The corbicular hairs of female B. lapidarius are black, not orange as in B. ruderarius. The males of B. lapidarius are generally brighter in colour and the genitalia are very different.
Widely distributed throughout Britain and Ireland. This species has been extending its range into northern Scotland in recent decades (M Macdonald, pers. comm.)