• Welcome to TONMO, the premier cephalopod interest community, and birthplace of #WorldOctopusDay and #CephalopodAwarenessDays. Founded in 2000, we are 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. You can also become a Supporter for just $50/year to remove all ads and enjoy other perks. Follow us on Twitter for more cephy goodness.

Peroniceras

Architeuthoceras

Architeuthis
Staff member
Moderator
Joined
Nov 19, 2002
Messages
2,445
Peroniceras haasi? from the Mancos Shale in Utah. Late Cretaceous (Coniacian) Scaphites preventricosus Zone. The inner whorls are broken and shifted so I dont think any more prep would help. Just something to post until some of this snow melts and I can get out and look for more. :boohoo:
 

Attachments

  • conv_302500.jpg
    conv_302500.jpg
    55.8 KB · Views: 63

Phil

TONMO Supporter
Supporter
Joined
Nov 19, 2002
Messages
3,033
Nice find Kevin, as ever!

That ammonite has a strongly defined keel. I wonder if that feature helped maintain directional stability in the water and acted as streamlining to a limited extent?
 

Architeuthoceras

Architeuthis
Staff member
Moderator
Joined
Nov 19, 2002
Messages
2,445
Thanks Phil. This genus actually had 3 keels (tricarinate), the shell on this specimen is gone but the internal mold shows remnants. Although there was probably not spines on the nodes they still probably offset any advantage the keels would provide.
 

Latest Posts

Forum statistics

Threads
20,984
Messages
207,027
Members
8,492
Latest member
DHF8

Monty Awards

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


Top