Endocerida

Endocerida
Temporal range: Floian–Hirnantian[1][2]
The massive endocerid Cameroceras (middle) alongside other nautiloids
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Nautiloidea
Superorder: †Endoceratoidea
Order: †Endocerida
Teichert, 1933
Families

† Cyrtendoceratidae
† Endoceratidae
† Proterocameroceratidae
† Yorkoceratidae

Endocerida is an extinct nautiloid order, a group of cephalopods from the Lower Paleozoic with cone-like deposits in their siphuncle. Endocerida was a diverse group of cephalopods that lived from the Early Ordovician possibly to the Late Silurian. Their shells were variable in form. Some were straight (orthoconic), others curved (cyrtoconic); some were long (longiconic), others short (breviconic). Some long-shelled forms like Endoceras attained shell lengths close to 6 metres (20 ft). The related Cameroceras is anecdotally reported to have reached lengths approaching 9 metres (30 ft), but these claims are problematic. The overwhelming majority of endocerids and nautiloids in general are much smaller, usually less than a meter long when fully grown.

  1. ^ Cite error: The named reference Kroger2009 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference Barskov2008 was invoked but never defined (see the help page).