Conularid

Silurian

Rochester Formation

Middleport NY USA.

Big 102mm conularid on 195mm slab.

Conulariid.

Conularids (aka conulariids) make up a group of cone or pyramid-shaped invertebrates that have been classified within the Phylum Cnidaria with which they share fourfold symmetry but their exoskeleton is quite different from any cnidarian.  Some paleontologists suggest the known genera should be assigned to their own phylum.  In outward appearance they might have resembled crinoids from a distance as they were also attached to a stalk anchored to hard objects on the seafloor.

Conularids were quite long-lived as a group, appearing in the Ordovician and dying out sometime in the Triassic.