Post by Joe Botting on Jun 23, 2005 5:20:43 GMT -5
I'm clearing my office out at the moment. As always, sorting and cataloguing means I have to have another look at specimens that might have been glossed over in the past, and once again, there are a couple of new discoveries, from a locality in the teretiusculus Zone shales a few miles from Llandrindod.
These are both firsts for the inlier as a whole, and quite surprising ones. (See www.asoldasthehills.org/Worms.html)
Firstly, there are three machaeridian sclerites. I've only personally found these before in Morocco and Scotland, but they're locally quite common. An articulated array of them, which form the skeleton of an armoured 'worm' (probably a primitive mollusc, actually) would be quite something; I happen to know that one of our members has a complete one from a similar age elsewhere in the Welsh Basin - any contribution, Mr. you-know-who-you are? ;-)
The other one is more bizarre. It is (I'm pretty certain, but not absolutely, categorically definite) the organic ('chitinous') tube of a priapulid worm. These things, characteristic of a Burgess Shale genus called Selkirkia, are extremely rare. They're effectively soft tissue, although not really soft, and I've not heard of any fossils of them from above the Cambrian. The preservation of this one is definitely helped by it being almost completely covered by encrusting bryozoans (another new species that I'll get round to drawing soon).
The surface itself is a shiny film with faint striations that are very characteristic of the genus. We were pretty sure it was a nautiloid when we found it... just goes to show, eh?
Joe
These are both firsts for the inlier as a whole, and quite surprising ones. (See www.asoldasthehills.org/Worms.html)
Firstly, there are three machaeridian sclerites. I've only personally found these before in Morocco and Scotland, but they're locally quite common. An articulated array of them, which form the skeleton of an armoured 'worm' (probably a primitive mollusc, actually) would be quite something; I happen to know that one of our members has a complete one from a similar age elsewhere in the Welsh Basin - any contribution, Mr. you-know-who-you are? ;-)
The other one is more bizarre. It is (I'm pretty certain, but not absolutely, categorically definite) the organic ('chitinous') tube of a priapulid worm. These things, characteristic of a Burgess Shale genus called Selkirkia, are extremely rare. They're effectively soft tissue, although not really soft, and I've not heard of any fossils of them from above the Cambrian. The preservation of this one is definitely helped by it being almost completely covered by encrusting bryozoans (another new species that I'll get round to drawing soon).
The surface itself is a shiny film with faint striations that are very characteristic of the genus. We were pretty sure it was a nautiloid when we found it... just goes to show, eh?
Joe