A first fly for London… nearly

Look at this lovely fly!

You could almost dive into that swimming pool of aquamarine/turquoise, its colour is so deep and inviting. Long legs, great markings. Just all round stunner!

And, I found it on my garden shed.

As flies go, it wasn’t too tricky to identify. It is a pretty big member of the Dolichopodidae family as a start and I believe the biggest in the UK.

An expert informed me that it can be found inland near “algal dominated leaks”. I’m kind of hoping there are no algal dominated leaks near my house and shed, but hey.

I checked NBN Atlas and there were a lot of records, mostly around the coast, but none in London. I love the idea of finding a London first record on my shed. In reality, it probably isn’t a first for London and iRecord shows that there are a couple of other records, but it clearly isn’t really a common find locally.

Apparently this poor fly species came close to losing its name due to some scientific mix-up. I hope it gets to keep it as I think Liancalus virens is pretty cool and suits it.

A turquoise metallic jewel and another highlight for my lockdown list.

Liancalus virens

Nature diary of a Nascent Pan-species Lister: 6 June 2020 (Fishers Green)

Got up very early on Saturday morning with a target of Nightingale, but was not successful. This is now multiple years in a row where I have tried, unsuccessfully, to hear Nightingale sing in London.

Highlights were my first calling Cuckoo for the year, views of singing Garden Warbler (one of six warbler species) and seeing the very young Black-headed Gull chicks on the Tern rafts (along with Common Tern also on nests).

Fishers Green is a lovely part of the Lee Valley water and woodland complex. I walked all around the Electricity Sub-station and some of the adjacent water bodies. A general observation was the amount of Dogwood (Cornus sanguinea) present; it really was everywhere.

I had a few plant galls of interest including my first ‘Sputnik gall’ for the year on Rose caused by the wasp, Diplolepis nervosa; they really are fantastic galls.

Sputnik gall (Diplolepis nervosa)

I recorded my first Italian Alder (Alnus cordata) – a non-native tree with noticeably more pointed leaves than our native alder – and the galls on it caused by mites, Acalitus brevitarsus and, seemingly, the angle gall Aceria nalepai (although the underside was a little confusing). This latter find is of real interest as A. nalepai is not recognised as causing galls on this particular host and I may return to collect some specimens for further examination.

Possibly two different mite galls on Italian Alder (Alnus cordata)

Other finds of note included:

Psyllopsis fraxini (agg) – an hemipteran causer of galls on Ash

A caddisfly (Athripsodes cinereus)

The Vapourer moth being its ridiculously showy self (Orgyia antiqua)