Paleocirroteuthis

Paleocirroteuthis is an extinct genus of octopuses that lived in the Santonian and Campanian ages of the Late Cretaceous Epoch.^[1][2][3] It is known from fossilized jaws discovered in Japan and Canada.^[3][5][4]

Paleocirroteuthis Temporal range: Late Cretaceous (Santonian - Campanian)[1] PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Order:	Octopoda
Suborder:	Cirrina
Genus:	†Paleocirroteuthis Tanabe et al., 2008[1][2][3]
Type species
†Paleocirroteuthis haggarti[1] Tanabe et al., 2008[3][4]
Other species[1][3][5]
†Paleocirroteuthis pacifica Tanabe et al., 2008

It contains two species, P. haggarti (the type species^[1][2]), and P. pacifica.^[1] Both species, along with the genus, were described by Kazushige Tanabe in 2008.^[1][2][5][4]

Etymology

The genus name consists of the Latin word cirrus (meaning "curl") which is prefixed and suffixed by the Ancient Greek words παλαιός (palaios, meaning "ancient") and τευθίς (teuthis, meaning "squid") respectively. When combined, they roughly translate to "ancient curly-haired squid".^[2]

P. haggarti is named after W. J. Haggart, a contributor to the Cretaceous Nanaimo Group's biostratigraphy, and P. pacifica is named after the Pacific Ocean, where the species was distributed.^[2]

Description

Paleocirroteuthis was large, comparable in size to a humboldt squid (Dosidicus gigas), as the lower jaw of specimen MCM-A872 (Paleocirroteuthis sp. nov. (?)) had a crest length of 54.9 millimetres (2.16 in)^[3], while the lower jaw of a humboldt squid caught off of Baja California, Mexico (UMUT 31004) measures in at a crest length of only 50.2 millimetres (1.98 in).^[6]

Classification

Paleocirroteuthis is placed in the suborder Cirrina, although its placement within Cirrina is unknown.^[1][2]

• Class Cephalopoda
  • Subclass Nautiloidea: nautilus
  • Subclass †Ammonoidea: ammonites
  • Subclass Coleoidea
    • Superorder Decapodiformes: squid, cuttlefish
    • Superorder Octopodiformes
      • Family †Trachyteuthididae (incertae sedis)
      • Order Vampyromorphida: vampire squid
      • Order Octopoda
        • Genus †Keuppia (incertae sedis)
        • Genus †Palaeoctopus (incertae sedis)
        • Genus †Proteroctopus (incertae sedis)
        • Genus †Styletoctopus (incertae sedis)
        • Suborder Cirrina: finned deep-sea octopus
          • Superfamily Opisthoteuthoidea
            • Family Opisthoteuthidae (containing Opisthoteuthis, Exsuperoteuthis & Insigniteuthis)
            • Family Grimpoteuthidae (containing Grimpoteuthis, Cryptoteuthis, & Luteuthis)
            • Family Cirroctopodidae (containing Cirroctopus)
          • Superfamily Cirroteuthoidea
            • Family Cirroteuthidae (containing Cirroteuthis, Cirrothauma, & Inopinoteuthis)
            • Family Stauroteuthidae (containing Stauroteuthis)
          • Family & Superfamily uncertain: †Paleocirroteuthis^[2]
        • Suborder Incirrina: octopus without mantle fins or cirri.