Creepy crawlies from the pit

[neuropteris]

Hi Folks

As a companion piece to the plants from the pit thread here are a few beasties from the same place. Although by no means as common finds as the plants there was still a diverse variety.

Firstly what is arguably the best find from the site (there are a few other contenders in different collections), a wing of the Palaeodictyopteran Anglopterum magnificum

i80.photobucket.com/albums/j178/neuropteris/Anglopterummagnificum1a.jpg

Next, a trigonotarbid arachnid Maiocercus celticus

i80.photobucket.com/albums/j178/neuropteris/Miaocercus10.jpg

Next an as yet unidentified insect found on one of my last visits to the place before it was filled in.

i80.photobucket.com/albums/j178/neuropteris/Insect3.jpg

Another insect but this time its a nymph, Rochdalia named after the town I was born in - Rochdale (some people say Gracie Fields is Rochdales greatest claim to fame - I say its Rochdalia)

i80.photobucket.com/albums/j178/neuropteris/Rochdalia1.jpg

And lastly another arachnid, this time a scorpion. Got quite a surprise when this nodule split to reveal its tiny but perfectly formed occupant, from the size and shape of the nodule I was only expecting a neuropteris pinnule. Needless to sayI was more pleased with the scorp.

i80.photobucket.com/albums/j178/neuropteris/Scorp5c.jpg

All the best

Andy

[Joe Botting]

Gorgeous again, Andy! I'm especially intrigued by the unknown insect, which I think you'll find is a cockroach. The pattern of venation in the wings is remarkably similar to modern ones (e.g. Periplanata americana). I know there are Carboniferous cockroaches known, but this is a lovely specimen...

Many thanks for posting them.

[neuropteris]

Hi Joe

I'd noticed a resemblance to the thingyroach aswell but it doesn't look quite like the 'classic' nodule roaches from Cosely or Mazon Creek. May well be one though (I was racking my brain as to why you'd termed it a thingyroach until I remembered the story of the problems suffered by the town of S***thorpe when they added a filter to stop suspect emails reaching them)

[Joe Botting]

Groan... yep, that's what it was. Should be sorted now, though. It's probably worth trying this with a fossil Blattoidea specialist (should such a thing exist...) - might be very interesting indeed.

[neuropteris]

I sent a latex mould off to Dr Nel at the French Museum of Natural History together with the photos last year but no id has come back so far. The photo is of the negative, the positive flaked when split and doesn't show anything like the same detail. But, these are preserved in 3d - both sets of wings are present superimposed one on the other so it could be that the body of the beastie is still buried in the other half of the nodule.

[reighan]

Thanks, Andy for the photos, and to you and Joe for the discussion. I learn all sorts of things here. ;D

If you don't mind some beginner's questions, I'm curious about the nodules, since I never know what I may find in the local tills. (Just as my collecting excursions began to wind down, I'd found some Coal Measures plant bits.) I don't think I see any iron in any of the nodules in the photos you've posted so far. Would the sandstone with iron or limonite nodules I find be worth a whack? (So far I've had no luck with the limonites I've opened, though one had a solid fat-almond-shaped core.) If there is something in a nodule, is it usually in the centre? Or if it splits and shows a clear central area, might something be showing more peripherally?

Reighan

[neuropteris]

Hi Reighan

The nodules are made of siderite - iron carbonate and while they are a grey colour when fresh they do oxidise over time to a reddish purple. In my experience, while ironstone nodules and bands are common in carboniferous sediments, well preserved fossils within are rare and tend to be found in relatively thin horizons - many of the nodules found at the locality those in the pics are from were barren so you'll have to be lucky to find them in a till. If the nodule has formed around something organic the fossil generally but not always lies in the middle and forms a plane of weakness in the nodule so, in theory, it should split along the this plane and reveal the contents. Keep on whacking them and good luck.

Andy

[reighan]

Thanks, Andy.

Reighan

[Joe Botting]

Just to broaden the question a bit, there are of course lots of other types of nodules. Many, unlike the carboniferous siderite ones, generally don't grow around fossils in particular, and any that are included are there by accident. This includes some spectacular things like the Herefordshire Lagerstatte, with its calcite nodules in a volcanic ash bed. On the other hand, we've seen nodules of pyrite with fossils right in the centre, and there are lots of other examples each way. There are also, of course, loads of complete abiological nodules that are no use to anyone except as cannonballs.

Speaking of which, if it's exceptional fossils you're after, look for spherical rather than flattened ones. This normally means that the nodule grew before compaction of the sediment, and therefore has a chance of preserving the fossils in a state before too much degradation has set in.