Learn about flies

I think I'm right in putting this pair in Cetema, beyond that I need help. As I understand it the Fennoscandia Frit-flies volume lists four species, three of which have long hairs on the anterior and mid tibiae of the male. I don't see those here which would suggest C. elongata. However, the UK checklist has 6 species in the genera and I don't know whether there is a publicly available key to the genus in the UK.

(Photo only, 11.vii.2020, marshy fields, VC55. Hopefully I'll be able to get a a specimen this year.)

Any help or comments appreciated.

Swept from flowering willow at same time as Egle ciliata, this is a much smaller fly. I think it is another species. Comparing with Michael Ackland's drawings and using his key I keep coming back to Egle parva except that the cercal plate does not seem to be narrowed basally. Almost fits E. minuta better but epandrium not hairy laterally. Now confused and stuck. Wrong Genus? Herts. 16 March 2021.

I found a phorid earlier in March, in my North Essex garden and, following advice, bought the RES handbook for the family (excluding Megaselia). Have keyed it out to Anevrina urbana but is anyone able to confirm?

My reasoning: no bristles or hairs seen on the mesopleuron (see 4th pic); tibia have isolated bristles in upper two-thirds (see 6th, 7th, 8th pics); hind tibia simply haired (see 6th pic); vein 3 forked (see 5th pic) and has over 10 hairs on dorsal face (not visible in any of my photos).

28.ii.2021, Leics, VC55. Scale is mm. Off pond sedge in a marshy field.

Confirmation / correction appreciated. Is there a UK key to the family?

From a marshy field just south of Leicester. I can take more images if required.

For a very brief instant, I detected some movement inside the pupa and saw the hoverfly pushing its head out first.

@ noon: pupa is still very dark but no changes yet.

It remained grey without any apparent changes for at least 5 more days. But on the morning of the 16^th July, the grey had turned black and I was worried that the fly would emerge during the night but when I checked it the next morning (17^th July), I saw that the pupa was still intact. I decided to keep a watch over it all day. @ 8.14 am: the pupa has now turned very dark and looks like it is just about to break up.