Phragmoteuthida Temporal range: Permian - Jurassic |
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Phragmoteuthis conocauda | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Clade: | †Belemnoidea |
Order: |
†Phragmoteuthida Jeletzky in Sweet, 1964 |
Families | |
See text. |
See text.
Phragmoteuthida is an order of coleoid cephalopods characterized by a fan-like teuthoid pro-ostracum attached to a belemnoid-like phragmocone.
Jeletzky 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 from the Jurassic of Dorset, England. Notes 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.