
1) Cretaceous ammonite
Found on
https://www.crosswordclues.com/clue/argonauticeras

Argonauticeras is an extinct ammonoid cephalopod genus that lived during the latter part of the Early Cretaceous, included in the Lytoceratida and found in lower and possibly middle Aptian marine sediments. It has been thought of as a subgenus of Ammonoceratites. Argonauticeras produced an evolute shell with a trapezoidal whorl section, slightly i...
Found on
http://en.wikipedia.org/wiki/Argonauticeras
No exact match found.