Revision of the willow catkin flies, genus Egle Robineau-Desvoidy (Diptera: Anthomyiidae), in Europe and neighbouring areas

Abstract

Egle Robineau-Desvoidy is a modest-sized genus of small blackish anthomyiids with a Holarctic and northern Oriental distribution. They are univoltine, interacting closely with the host plants of their seed-feeding larvae, mainly species of willow (Salix), but also poplar (Populus) and false tamarisk (Myricaria) support some species. Summaries are given of adult and larval habits based on published and new observations. Adult mouth part structure in relation to pollen feeding is treated in some detail. A taxonomic revision with illustrated descriptions and an identification key to males and females is given for all known West Palearctic species and a few more from Greenland and Central Asia. Seven new species are described: Egle anderssoni, E. ignobilis and E. suwai from Denmark and Sweden, E. inermoides from Spain, E. groenlandica from Greenland, E. setiapicoides from Uzbekistan, and E. subarcticoides from Israel. Egle polychaeta Griffiths, 2003 is considered identical with E. steini Schnabl, 1911 (syn. nov.). Egle groenlandica sp. nov. is only known from females and may be the first known case of a calyptrate fly reproducing parthenogenetically.