Leaf Litter Lovelies

Just two days ago I heard about the existence of the UK Hoverflies Larval Group on Facebook. I'm not at all sure quite how this Group managed to slip beneath my radar, but I immediately requested to join up and was quickly welcomed into the (admittedly rather niche) world of  hoverfly larva. What have I let myself in for? Or maybe it's better to ask, what have they let themselves in for...

Today I spent a rather pleasant hour or so grubbing about in the mostly Sycamore leaf litter in search of early stage hoverflies. I found lots of slugs, more Arion intermedius in an hour than I usually find in a year, plus lots of these slender annelids (?) 

I don't know if this is an annelid or not, but it seems to be segmented and has what could be a clitellum

Edit - I think this may be a Potworm (Enchytraeidae), about which I know nothing!

In terms of abundance, the next commonest creatures I encountered were these larvae. I think they are Tipulidae because they have weirdly enlarged projections around the spiracles. Despite finding loads of these today, all of my pics are crap. A selection follows

Craneflies have silly faces on their bums - who knew?!?

Presumably different species have different faces. I wonder if anybody's done a photo gallery of them all yet?

But I wasn't here for worms and cranefly larvae, I was after hoverfly larvae. Luckily for me, I found one

This green beauty is a hoverfly larva from the genus Melanostoma. As far as anyone seems to know, these have to be reared through to adulthood before they can be identified to species. At this time of year most other hoverfly larvae are probably fully fed and ready to overwinter, but Melanostoma are winter active. Not that it's very wintery here at the moment, it's decidedly mild in fact. A short while later I came across the first of several Melanostoma snacks 

A bizarre fly larva from the genus Lonchoptera

I see these tiny trilobite things quite often, they really are fascinating little creatures. I managed to make a short video clip of this one as it scuttled around the leaf surface

There are only six species of Lonchoptera on the British list, but again they are only identifiable by rearing through to adulthood. There's an old RES Key to the adults (KGV Smith, 1969) but the eternally amazing Mike Hackston updated the fifty year old key just last year. The link to his reworked key is here.

Melanostoma larva flip these delightful lonchopterids onto their back, stab down into the belly and suck out the body fluids. They also feed on Lauxaniid larvae, but I didn't knowingly see any of those. 

I did however see another dipteran larva that will happily predate Melanostoma (it's a fly eat fly world out there!) I owe this identification to Geoff Wilkinson on the UK Hoverflies Larval Group FB page

Phaonia sp (Muscidae) - a fierce predator and quite capable of killing the Melanostoma larva I found earlier

Once again it's a case of rearing it through to adulthood before being able to identify it to species. I didn't bring any larvae back with me, today. There's a very long way to go before it's springtime and they'd surely peg it if I tried to keep them alive.

So, my Diptera list remains at just one species for the year, but I really don't mind that. Today's enjoyment came through discovering all of these fly larvae, in all of their various guises, merrily doing their stuff, feeding, hunting and being hunted, all buried away from casual sight deep in the wet leaf litter. My little jolly through the woods has been a real eye-opener for me, it really has added a whole new dimension to my understanding and knowledge of the behaviour for some of the early stages of our fly families. It's not always just about pinning and keying, ticking and recording. Sometimes the bigger picture is far more colourful than expected. 

And craneflies have crazy faces on their arses - amazing!