At the time of year when many bee populations are declining, M. tricincta appears to be increasing, although it is generally only to be encountered around the inconspicuous flowers of red bartsia (Odontites vernus). In such situations it can be locally abundant and, as with other Melitta species, the males are usually more in evidence than the females.

The female of this species is one of the more attractive and distinctive bees which occur in Britain, the extremely long, golden pollen-collecting hairs on the hind tibiae being particularly notable. D. hirtipes is the only member of its genus which occurs in Britain.

Of the three species of Macropis which occur in western Europe, only one, M. europaea, is found in Britain. This species is unique in this country for having females which provision their nests with fatty floral oils, in addition to pollen.

A relatively recent addition to the British bee list, the first specimen having been found in West Sussex in 1984.

A rare cleptoparasitic bee which can sometimes be reared in small numbers from the stem-nests of its host, the megachiline bee Hoplitis claviventris.

Since recording began this has always been considered a rare cleptoparasitic bee, but during this century it has decreased alarmingly.

A few British bees, all megachilines, habitually nest in empty snail shells; one of these is O. aurulenta (the others being O. bicolor and O. spinulosa)

The males of this species are among the first of the solitary bees to appear in the spring, with one exceptional record as early as late February. They are shortly followed by the distinctive females.

This species is very closely related to M. tricincta and care is necessary to distinguish the two in collections. However, in the field, each species is usually readily identified by the flowers the bees visit. In addition, the present species is more widely distributed in Britain than its congener, being found in northern and western localities from which the other is absent.

Until recently this species was known as Psithyrus rupestris but Psithyrus has now been reduced to a subgenus within Bombus. This is a large cuckoo-bee which is a social parasite on the common and widespread red-tailed bumble bee, Bombus lapidarius. Both species are all black with a red tail, but the female parasite has darker wings. Identification keys and general biology are found in Sladen (1912), Free & Butler (1959), Alford (1975) and Prŷs-Jones & Corbet (1991).