Cordilura rufimana
The fore- and mid- tibia are clear yellow, whilst the hind tibia is dark brownish with the base narrowly, and the apex more broadly yellow, although I have seen specimens with very dark hind tibia. The darker colouration is most noticeable on the dorsal surface and the colour difference, compared to the anterior four legs, is not all that striking in some specimens in the collection of the Natural History Museum. Hackman's key (1956)[1] places this in the group of species with dark hind tibia, which leads me to think that this material perhaps needs re-examination! The setulae above vein R1 are quite variable, being dark and readily visible in some specimens (although always fine) but pale and far from conspicuous in others whilst C. pubera not infrequently does have 1-2 distinct setulae on this vein. Consequently, extreme care is necessary in separating this species and the male genitalia should be examined. Wing length: ♂ 4.4 - 5.1 - 5.9 mm (31); ♀ 4.9 - 5.2 - 5.5 mm (11).
References
An uncommon northern species found in marshes and fens besides rivers and standing water in upland situations. Hackman (1956)[1] describes it as "Especially abundant on wet, treeless Sphagnum bogs".
References
Mostly recorded from Scotland, especially from the Speyside area although extending northwards to Sutherland, but also from northern England (Yorkshire, Lancashire, Cheshire, Cumbria) and North Wales (Flint). Irwin (1974)[1] records it from Londonderry, Ireland. There is also a dubious record from Oxfordshire. Most records are for May and June (but extending to 19.vii).
World distribution: Palaearctic: European Alps, Czech Republic, Denmark, Estonia, Finland, France, Germany, Ireland, Netherlands, Norway, Poland, Slovakia, Sweden; Russia: northern European regions, eastern Palaearctic; Nearctic: Canada, USA.