Eupeodes luniger-ish?

Dillybythesea · #1 (**permalink**) 23-09-2011, 05:16 PM

Looking back at previous threads, it seems that comma-shaped marks not reaching sides, Y-shaped extension to female frons, shld be Eupeodes luniger? Except scutellum hairs in luniger are predominantly black, and I'm not sure these are? First individual...

And this was another indvidual, but seemed pretty similar, and I'll include muzzy shots but where the scutellum is showing?

Thanks for any help!

Geoff F · #2 (**permalink**) 23-09-2011, 07:19 PM

The potential problem with Eupeodes is that there are now a number of extra species which may have to be considered. But they are mostly rather uncommon or restricted in range so shouldn't cause any problems.

For example, there are Eupeodes species A and species B/C, plus bucculatus, nitens, nielseni and lundbecki which could potentially occur. But most people would never find any of them. However, they are always worth considering when using identification keys as most can be easily eliminated.

I think the crucial point concerning scuttellum colour is in the way you read the text.

The scuttellum of luniger is 'usually more than half black hairs'. But in reality this can often be difficult to see from photos.

So if we ignore this and return to the full keys.

Wing vein R 4+5 isn't excessively dipped - so not lapposyrphus species.

No apparent evidence of black hair on rear of front femur - so probably not nitens or nielseni (unlikely to be these anyway).

Black area of frons less than half (around one third black) - so not latifasciatus (which is at least half black).

Tergites 3 and 4 with spots not bands - so not bucculatus or Eupeodes species B. Spots don't reach the sides - so probably not corollae. And the spots aren't excessively pinched in the middle - so not lundbecki.

Which leaves luniger. Or possible Eupeodes species C if the forward extension to the frons is particularly wide and the side dusting is narrow. But an unlikely species to find.

I said, probably not corollae. If the spots just touched the sides then the mixture of scuttellum hair colour would be important in separating them.

So there it is - easy.