Orthonevra geniculata (Meigen, 1830)
Biology & ecology:
The larva of this species remains unknown, but is presumed to be aquatic like others of the genus. Generally found in mildly acid, boggy areas in Scotland, but also in fens in East Anglia and on heathland with base influences in southern Britain. Adults are usually found close to water where they will visit flowers, but also settle on bare patches and dead vegetation in the sun.
A scarce species that is found most frequently in the southern uplands and the highlands of Scotland, but with scattered records in England and Wales. Within England the main centres of occurrence are in East Anglia and the heathlands of Surrey, Hampshire and Dorset.
Status & conservation:
All trends suggest a decline in occurrence, although field experience suggests that northern populations are more widespread than maps currently suggest.