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Scaeva selenitica (Meigen, 1822)

Identification

Identification difficulty = 2. magnifier_icon camera_filled_icon according to Ball & Morris, 20241

Biology

The larva feeds on aphids on Pine Pinus sp. and Spruce Picea sp. A puparium has been found under the bark of Spruce. Records that make reference to habitat most frequently specify woodland (including both deciduous and coniferous), although open habitats, such as chalk grassland, are also mentioned. In the south of England this species is mainly associated with pine plantations on heathland. Adults are often seen visiting flowers, such as white umbels, along woodland rides and edges and males hover in clearings.

Flight period

The following plots show the number of unique records per week excluding those reported to be of immature stages. Phenology plots for Scaeva selenitica

Distribution

Scarce but widely scattered. Whilst Stubbs & Falk (1983)2 state that it is at least a partial migrant, Falk (1991)3 argues that it is resident. There have been several very early spring records recently that suggest over-wintering by adults. It is quite possible that a resident population receives reinforcement by migration from the continent. Distribution map for Scaeva selenitica

Trends

The following plots show the Frescalo TFactor vs year and a map of the rescaled frequency (all records) for the species.Trend plots for Scaeva selenitica

  1. Ball, S., & Morris, R. (2024). Hoverflies of Britain and Ireland. WILDGuides (3rd ed.). Oxford: Princeton University Press. ↩

  2. Stubbs, A., & Falk, S. (1983). British Hoverflies: An Illustrated Identification Guide (1st ed.). Reading: BENHS. ↩

  3. Falk, S. (1991). A review of the scarce and threatened flies of Great Britain. ( No. 39). Research and Survey in Nature Conservation (pp. 1–194). Peterborough: NCC. ↩