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Octopoda Leach, 1818

Octopods or devilfishes

Katharina M. Mangold (1922-2003), Richard E. Young, and Michael Vecchione
The Octopoda contains about 200 species placed in two very different groups.
Containing group: Octopodiformes


Octopods have rather short, compact bodies and only eight arms; no trace of the missing second arm pair remains even during embryonic development. Many species are benthic (bottom-living) and crawl over the ocean floor with the mouth facing the substratum. Others alternate between a benthic and a pelagic (free-swimming) habitat and some species are completely pelagic. The two suborders of Octopoda are very different in appearance but there is little doubt that it is a natural group as the monophyly of the Octopoda is supported by a large variety of characters. The Cirrata is a group of deep-sea octopods commonly known as the "finned octopods" due to their large, wing-like fins. The Incirrata contain the common (benthic), shallow-water octopods as well as many deep-sea benthic and pelagic species.


  1. Head
    1. Head and mantle fused in nuchal region.
  2. Viscera
    1. Visceropericardial coelom reduced.
    2. Oviducal glands act, in part, as spermathecae.
    3. Oviducts with oviducal glands subterminally located on oviducts.
    4. Dorsal mantle cavity present.
    5. Nuchal cartilage absent.
  3. Arms
    1. Sucker stalks are broad, muscular cylinders.
  4. Photosensitive vesicles
    1. Located on stellate ganglia.
  5. Funnel valve
    1. Absent.
  6. Central nervous system
    1. Inferior frontal lobe system present.
    2. Superior buccal and posterior buccal lobes fused.
    3. Suprabrachial commissure separate from brain (absent in Japetella).

Discussion of Phylogenetic Relationships

The monophyly of both suborders is well established. Young and Vecchione (1996) found two apomorphic character states that defined the monophyly of the Incirrata:

Another character can probably be added to the list of apomorphies although it hasn't been included in a cladistic study:

Young and Vecchione (1996) found three character states that defined the monophyly of the Cirrata:

Voight (1997) also found morphological, cladistic support for the Cirrata and Incirrata but her study is controversial. Carlini (1998) found molecular analyses supported the monophyly of both groups.


Carlini, D. B. 1998. The phylogeny of coleoid cephalopods inferred from molecular evolutionary analyses of the cytochrome oxidase I, muscle actin, and cytoplasmic actin genes. Ph.D. diss. Coll. William and Mary, 273 pp.

Young, R. E. and M. Vecchione. 1996. Analysis of morphology to determine primary sister taxon relationships within coleoid cephalopods. Amer. Malac. Bull. 12: 91-112.

Young, R. E., M. Vecchione and D. Donovan. 1999. The evolution of coleoid cephalopods and their present biodiversity and ecology. South African Jour. Mar. Sci. (in press).

Voight, J. R. 1997. Cladistic analysis of the octopods based on anatomical characters. J. Moll. Stud., 63: 311-325.

Title Illustrations
Scientific Name Octopus
Location Hawaii
Life Cycle Stage young
Copyright © 1996 R. E. Young
About This Page

Katharina M. Mangold (1922-2003)

Richard E. Young

Dept of Oceanography
University of Hawaii
Honolulu, Hawaii 96822

National Marine Fisheries Service
Systematics Laboratory
National Museum of Natural History
Washington, D. C. 20560

Citing this page:

Mangold (1922-2003), Katharina M., Young, Richard E., and Vecchione, Michael. 1996. Octopoda Leach, 1818. Octopods or devilfishes. Version 01 January 1996 (under construction). http://tolweb.org/Octopoda/20083/1996.01.01 in The Tree of Life Web Project, http://tolweb.org/

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