Cleigastra apicalis
An easily recognised species usually with a distinctive black mark on the outer face of the fore femora and, on closer examination, a combination of three sternopleural bristles and setulae on the upper surface of vein R1. Wing length: ♂ 4.0 - 5.2 - 6.1 mm (13); ♀ 4.5 - 5.5 - 6.3 mm (11).
A predatory fly which is locally abundant in reed beds, especially, but not exclusively, where Phragmites grows (I have found it in abundance in water traps placed in a Typha bed). The larvae have been found associated with Lipara galls and a puparium has been found in an empty gall. According to Smith (1989) (citing Groth, 1969) they are also claimed to be associated with the stem boring caterpillars of twin-spotted wainscot, Archanara geminipuncta and fen wainscot, Arenostola phragmitidis.
World distribution: Palaearctic: Belgium, Czech Republic, Denmark, Estonia, Finland, France, Germany, Hungary, Ireland, Italy, Lithuania, Netherlands, Norway, Poland, Slovakia, Sweden, Switzerland, Russia: north European region.