Phragmoteuthida

Phragmoteuthida is an order of extinct coleoid cephalopods[1] characterized by a fan-like teuthoid pro-ostracum attached to a belemnoid-like phragmocone.

Phragmoteuthida
Temporal range: Permian - Jurassic
Phragmoteuthis conocauda
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Superorder: †Belemnoidea
Order: †Phragmoteuthida
Jeletzky in Sweet, 1964
Families

See text.

Diagnosis

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]

Classification
  • Order †Phragmoteuthida
    • Family †Phragmoteuthididae
    • Family †Rhiphaeoteuthidae
      • Genus †Rhiphaeoteuthis

References
  1. Doguzhaeva, L. (2002). "Adolescent bactritoid, orthoceroid, ammonoid and coleoid shells from the Upper Carboniferous and Lower Permian of the South Urals" (PDF). Abhandlungen der Geologischen Bundesanstalt. 57: 9–55.
  2. Donovan, D.T. (May 2006). "Phragmoteuthida (Cephalopoda: coleoidea) from the Jurassic of Dorset, England". Palaeontology. 49 (3): 673–684. doi:10.1111/j.1475-4983.2006.00552.x.CS1 maint: date and year (link)
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