First British record of Megatoma undata (Linnaeus) (Dermestidae) from nests of the red mason bee, Osmia rufa (Linnaeus), with observations on larval behaviour

摘要

A large nesting population of the red mason bee, Osmia rufa (Linnaeus) (Hymenoptera: Apidae: Megachilinae) was maintained in a Leicestershire garden for five years. The dermestid, Megatoma undata (Linnaeus), was discovered in a few nests in Year 2 of the project and in all subsequent years. The Megatoma larvae fed on larval exuviae of the bee, their faecal pellets and on the silk cocoons spun by the pre-pupal bees (= post-defaecating larvae). The beetle larvae also fed on dead adult bees in their cocoons. The association of Megatoma undata is opportunistic but may have negative effects on populations of the bee. The functional significance of the long cuticular spines in the moulting process of Megatoma larvae was inferred by direct observation of the behaviour of moulting and may well apply to other species of Dermestidae.