Early Waspgrabber Leopoldius brevirostris

This came to light and initially I had no idea what it was. It had what looks like a vena spuria which caused me to think it must be a hoverfly (Syrphidae), although this was not as long as the vena spuria of hoverflies. Having failed to find anything similar among the hoverflies I came across some images of very similar-looking Conops flies and looked for a Conopidae key. Mike Hackston's key seemed to lead to Leopoldius brevirostris, especially because of the pair of thick black lines down the frons, but the dark dorsal patches on some of the femora were potentially problematic as brevirostris usually lacks these (unlike the commoner signatus). Moreover all accounts seemed to suggest this was quite a rare species, so the chances of me having made a mistake seemed high, although the date (July) did support the ID as being brevirostris as signatus flies later in the year. I wasn't entirely sure which bit of the fly was the epandrium, or how this was best viewed, so I contacted Mike for clarification.

Although Mike responded promptly, I didn't actually look at it again unitl 2025 after I'd found three more Leopoldius flies, all of which proved to be the commoner Ivy Waspgrabber Leopoldius signatus. I found that not only was the epandrium easier to view after clearing the abdomen in potassium hydroxide solution, but to get a strong match to the diagrams in the key you had to view this from the front, i.e. more-or-less along the axis of the insect. Having secured an ID of these, I thought it would be a good time to revisit this one from 2020. Hackston's key was still the best resource I could find, and I was reassured after clearing the abdomen and viewing the epandrium the correct way (and comparing it to those of the signatus) that this was indeed brevirostris.

male Early Waspgrabber Leopoldius brevirostris showing proboscis, frons (2 angles), femora, abdomen from side, epandrium in context and epandrium viewed from front, Bintree Wood (Norfolk, UK), 24th July 2020