Coremacera halensis Loew, 1847

Coremacera halensis Loew, 1847 View in CoL

Fig. 10 View Fig

Material: France, Provence-Alpes-Côte d'Azur region, Greolieres [43.795 ° N, 6.943 ° E], 24.08.1979, Heitmans, 1♂ ( ZMUM) GoogleMaps .

Discussion. Both Rozkosny (1987: 45–47) and Vala (1989: 147–154) characterized C. halensis as species similar to C. fabricii . According to the authors these species differ as follows:

— Anterior wing margin mainly dark brown, at most with 3–5 small pale spots. Mesonotum densely grey dusted; with large and distinct dark spots around bases of setulae (as in C. marginata ) and with some larger brown spots in addition. Postpedicel of equilateral triangle shape, shorter. Femora bicolour, with dark bases........... halensis Loew. — Anterior wing margin mainly pale, with more numerous pale spots. Mesonotum thinly dusted, brownish; with small dark spots around bases of setulae and with larger brown spots absent or indistinct. Postpedicel of trapezoid shape, elongated. Femora unicolour..... fabricii Rozkosny. I have a single male from France which entirely fits C. halensis criteria ( Fig. 10 View Fig ). All 20 specimens from Central European Russia listed here entirely fit C. fabricii criteria. This is an argument for the validity of C. halensis . However, there are serious arguments against it as well. (1) Genitalia of the male identified as C. halensis was examined and found the same as in C. fabricii . (2) To fill the lack of Western European material I examined images of C. fabricii at https://diptera.info/ photogallery.php site. I found interesting images from Germany, Wernigerode [51.8 ° N, 10.8 ° E], 8.05.2009 ( Figs 11, 12 View Figs 11–12 ). Both specimens were photographed at the same place and time, they look as typical C. fabricii except for the wing pattern. A female has the wings of C. halensis , while male has those of C. fabricii . Thus, the wing pattern can’t be used as reliable diagnostic character.

Comparing this case with C. m. pontica, I believe that most probably there are two subspecies: C. halensis halensis in the very west of Europe and C. halensis fabricii in the rest of the territory, with a contact zone in Germany. More European material is required for final conclusion.