Volucella inanis

[stuart]

Volucella inanis (Linnaeus, 1758)

Identification ease/difficulty: 2

Status

• Notable in Falk (1991)

Sources of information

• Page 216, Pl. 8, fig 4 in Stubbs & Falk (1983)
• Larval plate Pl. 4a in Rotheray (1993)
• Map here and page 144 in Ball & Morris (2000)
• Page 323, Pl. 8, fig. 4 in Stubbs & Falk (2002)

Pictures:

[stuart]

Species account from Provisional atlas of British hoverflies, Ball & Morris, 2000.

Volucella inanis (Linnaeus, 1758)

Biology: The larvae are ectoparasites of social wasp larvae, and have been found in association with Vespula germanica and Vespa crabro. They are, unlike any other member of the genus, very flattened so that they fit into the larval cells beside the wasp larvae on which they feed. Found in open areas in woodland and scrub and, most frequently, in suburban areas, in parks and gardens. Adults are usually seen visiting flowers, especially white umbels and Buddleja

Distribution: Locally abundant in the outer suburbs of London and the surrounding countryside. There are a few records away from this area, including scattered localities along the south coast from Kent to Cornwall, the Bristol area, South Wales and Oxfordshire

[stuart]

Datasheet from the Review of Scarce and Threatened Diptera, Falk (1991).

VOLUCELLA INANIS (Linnaeus) NOTABLE

DISTRIBUTION Southern England from Kent to Cornwall and north to Oxfordshire. Records most frequent in south east England, in particular Kent, Sussex, Surrey, Middlesex and Essex.

HABITAT Preferences unclear, though records include scrub, heaths, chalk grassland and ruderal sites well into urban areas including London, where it can be particularly numerous.

ECOLOGY The larvae develop as commensals in nests of wasps including Vespula germanica, V. vulgaris and Vespa crabro. The larvae probably feed on organic debris accumulating in the nest cavity below the nest itself. Adults recorded from July to September and visit a range of flowers especially favouring thistles Carduus and Cirsium.

STATUS Regular and locally frequent in the Greater London area, less so elsewhere in the south east. About 30 known post 1960 sites.

THREAT This species does not seem to be unduly threatened by mans activities and actually seems to thrive in suburbs perhaps due to enhanced populations of certain wasps. The restricted range seems to be purely a response to climatic factors.

MANAGEMENT Maintain a range of conditions at sites including open rides and clearings within woodland, some limited scrub or bushes on grassland and heathland, but prevent excessive scrub invasion through rotational cutting or grazing where necessary.