Botria (=Bothria) subalpina is a Spring species previously thought to be found in northern & eastern Europe – I have specimens from Finland and Bavaria. But recently Murdo Macdonald sent some flies to the National Museum of Scotland and David Horsfield spotted a fly that keyed out to Bothria subalpina in the Central European key. He sent the specimen to Hans-Peter Tschorsnig in Germany who confirmed the identification!
Apparently the name has changed from Bothria to Botria due to a Rondani misspelling that has only recently come to light. Also Villeneuve wrote in his 1910 type description for subalpina that he had been sent a specimen taken near Birmingham by Wainwright. It would be interesting to track down this specimen and confirm the identification and locality.
Here is a photo of a specimen from Finland and a very bad photo of one from Germany:
Currently, in Belshaw, this species would get lost around couplet #27 because it looks like it should go to #28 (Phorocera/Parasetigena) but the basals are between 2-3x as long as the scutellum so it is weak here and of course if you go to #28 it isn’t Parasetigena because Botria has median discals and it isn’t Phorocera because the male genitalia are all wrong (smaller than Phorocera) and it has pale tibiae. I think the pale tibiae are probably the best way to split Botria out but I need to double-check all of the other alternatives from #27 onwards.