Cirrina

Cirrina
Oral view of Cirrothauma murrayi showing single row of suckers and paired cirri
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Order:	Octopoda
Suborder:	Cirrina Grimpe, 1916 sensu Felley et al., 2001
Families
Opisthoteuthidae Cirroteuthidae Stauroteuthidae
Synonyms
Cirrata Grimpe, 1916 Cirroctopoda Young, 1989

Cirrina or Cirrata is a suborder and one of the two main divisions of octopuses. Cirrate octopuses have a small, internal shell and two fins on their head, while their sister suborder Incirrina has neither.

The suborder is named for small, cilia-like strands (cirri) on the arms of the octopus, a pair for each sucker. These are thought to play some role in feeding, perhaps by creating currents of water that help bring food closer to the beak. Cirrate octopuses are noteworthy for lacking ink sacs.

Classification

• 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 †Paleocirroteuthis (incertae sedis)
        • Genus †Pohlsepia (incertae sedis)
        • Genus †Proteroctopus (incertae sedis)
        • Genus †Styletoctopus (incertae sedis)
        • Suborder Cirrina: finned deep-sea octopus
          • Family Opisthoteuthidae: umbrella octopus
          • Family Cirroteuthidae
          • Family Stauroteuthidae
        • Suborder Incirrina

External links

• Cirrata at the Tree of Life Web Project
• Cirrate male reproductive tract at the Tree of Life Web Project