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Portevinia maculata (Fallén, 1817)

Identification

Identification difficulty = 1. eyeball_icon camera_filled_icon according to Ball & Morris, 20241

Synonymy

Cheilosia maculata Fallén in Coe(1953)2.

Biology

The larva tunnels in the bulbs of Ramsons Allium ursinum. During its short flight period, males are often abundant around stands of the larval food plant, where they can be seen visiting the flowers and resting on the foliage. Females generally fly low down amongst the plants and are more difficult to find.

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

Distribution

Although very widely distributed, this species is most frequently found in more heavily wooded regions. Current data suggest that cooler regions are preferred and the comparative lack of records from the south and east where recorder effort is highest may be indicative of this. Woodlands in the Pennines and southern Scotland are exceptionally suitable. 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. Coe, R. (1953). Diptera: Syrphidae. Handbooks for the Identification of British Insects, 10(1), 1–98. ↩