Dichotomous Key/Octopoda

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Dichotomous Key: Octopoda
Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Subclass: Coleoidea Superorder: Octopodiformes Order: Octopoda

[edit] 1

• Cornea
  • Present - 2
  • Not present - 3

[edit] 2: Incirrata

• Detachable hectocotylus
  • Present - 5
  • Not present - 6

[edit] 3: Cirrata

• Secondary web
  • Present - 4
  • Not present - Opisthoteuthidae

[edit] 4

• Shell shape
  • Saddle-shaped - Cirroteuthidae
  • U-shaped - Stauroteuthidae

[edit] 5: Argonautoida

• Tissue consistency
  • Gelatinous - 10
  • Muscular - 9

[edit] 6

• Eye shape
  • Tubular - Amphitretidae
  • Other - 7

[edit] 7

• Eye shape
  • Laterally compressed - Bolitaenidae
  • Other - 8

[edit] 8

• Eye shape
  • Rectangular - Vitreledonella richardi
  • Other - Octopodidae

[edit] 9

• Web
  • Absent or greatly reduced except in four dorsal arms - Tremoctopodidae
  • Consistent - 11

[edit] 10

• Web
  • Absent or greatly reduced except in four dorsal arms - Tremoctopus gelatus
  • Consistent - Haliphron atlanticus

[edit] 11

• Funnel locking-apparatus
  • Contains circular pit - Argonautidae
  • Does not contain circular pit - Ocythoe tuberculata