Phragmoteuthida

Phragmoteuthida Temporal range: Permian - Jurassic
File:Phragmoteuthis conocauda 1.JPG
Phragmoteuthis conocauda
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Cohort:	†Belemnoidea
Order:	†Phragmoteuthida Jeletzky in Sweet, 1964
Families
See text.

Phragmoteuthida is an order of coleoid cephalopods characterized by a fan-like teuthoid pro-ostracum attached to a belemnoid-like phragmocone.

Diagnosis

Jeletzky characerized 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.

Classification

• Order Phragmoteuthida
  • Family Phragmoteuthididae
    • Genus Permoteuthis
    • Genus Phragmoteuthis
    • "unnamed form"
  • Family Rhiphaeoteuthidae
    • Genus Rhiphaeoteuthis

References

• D.T. Donovan 2006. Phragmoteuthida (Cephalopoda: coleoidea) from the Jurassic of Dorset, England. Palaeontology Vp; 49 Issue 3 pp 673 -684 May 2006. [1]