The Highland Biological Recording Group

Solitary Aculeates

The solitary aculeates are so-called because they generally have no castes (like the social bees, wasps and ants), and establish nests with just one female who lays eggs. Confusingly, though, they may live in large dense colonies or aggregations. There are 12 families and around 550 species in the UK (69 species in genus Andrena alone).

They are generally much less obvious and scarcer than the social species, and are more dependent on warm sunny weather for their activity. They may best be found at the south-facing clay or sandy banks which are good nesting sites. It is possible to find several species of bee and wasp together at one place, and possibly also Beeflies Bombylius major which live in the bee nests

Life histories much more varied than those of the social bees and wasps, but they have no well-developed worker caste (hence 'solitary'), though some species are eusocial with some sterile females acting as workers for the breeding female in the nest.

Some solitary bees are reliant on a single species or small group of forage species to provide pollen (oligolectic), while others are polylectic. Some of the solitary wasps have specific prey, such as caterpillars, aphids or spiders. A number of genera are host-specific parasites or kleptoparasites on other solitaries.

The knowledge of solitary aculeates in Highland is sketchy to say the least, so all specimens are valuable.

The table lists some Highland species (K = kleptoparasite, BAP = UK BAP species).

Ancistrocerus parietinus	Andrena haemorrhoa *	Arachnospila anceps	Megachile centuncularis *
Andrena barbilabris *	Andrena helvola	Argogorytes mystaceus	Nomada marshamella (K) *
Andrena cineraria *	Andrena marginata *	Hylaeus confusus *	Mimumesa dahlbomi *
Andrena clarkella *	Andrena scotica *	Evagetes crassicornis (K)
Andrena coitana	Andrena tarsata (BAP) *	Lasioglossum leucopus

Solitary aculeates cannot be identified without technical keys and a microscope, so specimens are required. These may be killed by freezing, and then air-dried. If being sent by post, an old film canister with a piece of tissue is sufficient.

Records can be reported initially by email giving date, place, six-figure grid reference and any other relevant details. Directions for sending specimens (which will always be required for confirmation) will then be provided.