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Bumblebees have been confused with many other insects. While an experienced observer distinguishes the most common bumblebee species by sight, beginners should try to identify a number of specimens using the guide. Simplified identification tables generally take up the colour patterns of queen and worker bumblebees. Since the colouring of male bumblebees sometimes varies, it is easy to make a mistake even here. The colours can also fade. Some species have dark forms, and also regional variations.

 

Bumblebees are generally larger than solitary bees and honey bees. Although some worn individuals may have bald patches on the thorax, bumblebees do not have totally hairless segments on the abdomen (rear body). The cuticle of bumblebees is always black. On closer examination we can also see differences in the wing vein pattern between bumblebees and other bees, particularly at  the forewing front area. To distinguish bumblebees from hoverflies (Syrphidae), bee flies (Bombyliidae) and hawkmoths (Hemaris), observe the behaviour and examine antennae and wings carefully.

 

The antennae of flies are short, three-segmented. The antennae of bumblebees have a knee-like joint, those of the hawkmoths (Hemaris) are straight. A reminder: flies have only one pair of wings, but butterflies and membrane-winged insects (Hymenoptera) have two pairs. Bumblebees visit flowers diligently; hoverflies (Syrphidae) and hawkmoths (Hemaris) characteristically have intermediate periods of hovering flight.

 

A feature that helps to distinguish bumblebees from cuckoo bumblebees is the pollen basket (corbicula) on the hind leg – an enlarged, shiny part of the rear shank bordered by long hairs along the edges. Cuckoo bumblebees characteristically have more sparse hairs through which the black cuticle is visible, often producing a V-shaped mark on the abdomen.

 

They can also be identified by sound and behaviour: cuckoo bumblebees, with a lazier and more mellow-sounding hum, like to gather on flowers rich in nectar towards the end of summer and have no hurry to leave. Cuckoo bumblebees have no workers. They can be present together with true bumblebee males who are longer than the workers, having  a 7-segmented body whereby they seem more slender and can be mistaken for cuckoo bumblebees. All males lack both sting and the pollen collecting basket.

 

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