conulariids

[tqb]

After finding a few rare Carboniferous conulariids in County Durham, I've been lured into buying a few specimens from around the world.

This beautifully preserved Ordovician one is from the Verulam Formation, Brechin, Ontario but I can't find much information on them.

Does anyone have a generic name or reference for it? - the publications I've found seem to just call them conulariids.

Thanks for looking!

[ryanc]

I didn't realise they had chalk in the Ordovician? I guess it's a limestone produced far from land sediments?

It really is amazingly well preserved - the limestone buffering the calcite from chemical weathering perhaps.

Their offsetting and lack of real symmetry must really upset the systematic palaeontologists

A trawl turned up Eoconularia from the Lower Verulam Formation of Ontario as a good suspect.

Regards,

Ryan

[Joe Botting]

I've called in the cavalry on this one, folks... Heyo Van Iten in a friend of ours, so hopefully (no guarantees - he may be off adventuring somewhere, or just really busy) he'll drop in and lend us his expertise on this one. If so, I'd recommend posting some pictures of any other ones you happen to have as well...

It's a beautiful specimen, anyhow. These are really lovely things when they're well preserved.

[Joe Botting]

Response from Heyo:

The conulariid in question is Conularia trentonensis Hall (very widespread in the Upper Ordovician of cratonic North America). A very similar close relative occurs in Scotland (our territory on temporary loan to Europe).

[tqb]

Thanks very much to you and him, Joe, I'm very grateful you could rustle up a specialist!


Just a couple more specimens for now:

First, I think you once told me about huge specimens from Morocco - here's a large bottom end of one with very fine ornament, sold as from the Ordovician, Hamar Laghad, Erfoud.
Do you know if these have been described?

[tqb]

And a Middle Devonian one, sold as Conularia quichua, from Sica sica, La Paz, Bolivia. Pretty common around there but this looked better than most.

It seems to be a radial cluster showing four converging specimens - I'm tempted to prep it out.

Opened nodule, positive on right:

[tqb]

Closeup of the last one: