| Phragmoteuthida | |
|---|---|
| | |
| Comparation of hard parts of Phragmoteuthida, Belemnitida and Diplobelida | |
| Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Superorder: | † Belemnoidea |
| Order: | † Phragmoteuthida Jeletzky in Sweet, 1964 |
| Families | |
See text. | |
Phragmoteuthida is an order of extinct coleoid cephalopods [1] characterized by a fan-like teuthoid pro-ostracum attached to a belemnoid-like phragmocone.
Jeletzky [1] characterized phragmoteuthids as having a large tripartite, fanlike pro-ostracum forming the longest portion of the shell, attached to about three-quarters of the circumference of a comparatively small breviconic phragmocone with short camerae and superficially belemnitid-like siphuncle, an absent or much reduced rostrum at the apical part of the phragmocone, belemnite-like arm hooks, an ink sack, beaks resembling those of Recent teuthids, and a muscular mantle.
Donovan (2006), gives a similar description for Phragmoteuthis : Phragmocones as having an apical angle of between 20 and 30 degrees, and relatively few chambers compared with belemnoids; a multi-layered conotheca, thick-walled siphuncle, and a long, three-lobed pro-ostracum as in the Triassic species. Arms are short and bear pairs of slightly curved hooks. [2]