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Platycheirus perpallidus Verrall, 1901

Identification

Identification difficulty = 3. microscope_icon camera_icon_cross according to Ball & Morris, 20241

Biology

This is a wetland species that occurs along the margins of ditches, ponds and mires, especially where sedges Carex sp. occur in poor fen. The larva is predaceous upon the sedge aphid Trichocallis cyperi; there are also records of associations with the aphids Hyalopterus pruni on Lesser Reedmace Typha angustifolia and Subsaltusaphis rosseri on the sedge Carex rostrata. Adults seem to prefer the water-side edge of wetland vegetation.

Flight period

The following plots show the number of unique records per week that were not reported to be of eggs, larvae or pupae. phenology

Status

Lower Risk (Nationally scarce) - Ball & Moris, 20142. Notable - Falk, 19913.

Distribution

This is mainly a northern and upland species that is widely distributed across Scotland and northern England, extending into Wales down to the Severn Estuary. There are no recent records south of the West Midlands, so the reduction in range appears to represent a retreat northwards. The single record from South Wiltshire in 1949 needs to be treated with caution! dotmap

Trends

The following plots show the Frescalo TFactor vs year and a map of the rescaled frequency (all records) for the species. For an explanation see here. trend

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

  2. Ball, S., & Morris, R. (2014). A review of the scarce and threatened flies of Great Britain. Part 6: Syrphidae. ( No. 9). Species status (pp. 1–130). Peterborough: JNCC. ↩

  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. ↩