• Welcome to TONMO, the premier cephalopod interest community. Founded in 2000, we have built a large community of experts, hobbyists and enthusiasts, some of whom come together when we host our biennial conference. To join in on the fun, sign up - it's free! You can also become a Supporter for just $50/year to remove all ads and gain access to our Supporters forum. Follow us on Twitter and Facebook for more cephy goodness.

Quantoxhead Ammonite

Roy

Hatchling
Registered
Joined
Mar 26, 2004
Messages
3
Hi,

I'm new to this discussion board, but I'm hoping to direct some discussion trafic from my own fossil website 'Discovering Fossils'.

For those with an interest in Ammonites, we visited a location in North Somerset last weekend called Quantoxhead. The site is undergoing rapid erosion and conseuqntly the Jurassic cliffs are revealing a large volume of excellent fossils.

I'm attaching a picture of the best find of the day.

Later in the year we'll be returning to the site to film a BBC documentary, so watch this space, as we'll be asking for volunteers to accompany us on the day.

Roy
 

Phil

TONMO Supporter
Supporter
Joined
Nov 19, 2002
Messages
3,033
Wow! What a beauty! That's a great specimen.

Now I think, but am by no means certain, that the ammonite is an example of the unpronounceable Psilocertaceae, though I doubt it is Psiloceras itself (need to find a few more comparison pictures, Psiloceras seems to be generally smoother).

The Psilocertaceae were a very early group of the true ammonites (Ammonitina), appearing at the base of the Jurassic about 205 million years ago, becoming a successful flourishing group before disappearing about 190 mya. Psiloceras itself is used as a boundary fossil in UK stratigraphy in the early Jurassic.

These forms of ammonite often display differences in structure betwen the males and females, and well preserved examples sometimes have an enigmatic structure known as the anaptychus within the large body chamber. This is a semi-circular structure that has been variously interpreted as a form of door with which the ammonite could have closed off its living chamber, or possibly part of a jaw structure.

Thats a great location, Roy. That ammonite is twice as old as the stuff I find!

Phil

:ammonite:

PS. Volunteer!!!!!!!
 

Forum statistics

Threads
20,869
Messages
206,775
Members
8,458
Latest member
AuroraVK

Monty Awards

TONMOCON IV (2011): Terri
TONMOCON V (2013): Jean
TONMOCON VI (2015): Taollan
TONMOCON VII (2018): ekocak


Top