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Didea intermedia Loew, 1854

Identification

Identification difficulty = 4. microscope_icon camera_icon_cross according to Ball & Morris, 20241

Biology

The larva is strongly associated with Pinus. Adults are almost always associated with coniferous forest, including conifers planted on sand dunes. A few records from deciduous woodland in southern Britain are suspect, and may well be misidentifications of D. fasciata. Adults are flower visitors and can be found at yellow composites. In Scottish pinewoods they can often be found visiting White Bedstraw Galium saxatile, sometimes in considerable numbers.

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 & Morris, 20142. Notable - Falk, 19913.

Distribution

A northern species, with most records from Scotland and north-west England. It occurs on coniferised heathland on the Surrey/Hampshire border, and on the heathlands of Dorset and Hampshire. 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. ↩