Oegopsida
Richard E. Young and Michael VecchioneThis tree diagram shows the relationships between several groups of organisms.
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close boxIntroduction
Among cephalopods, oegopsid squids dominate the pelagic, oceanic environment. Diversity at the family and generic levels is very high with 24 families and 69 genera. Although pelagic, some species are consistently associated with and some occasionally sit on the ocean floor.
Diagnosis
Decapodiforms ...
- without cornea covering eyes.
- with a gladius.
Characteristics
- Arms
- Suckers without circularis muscles.
- Tentacles
- Tentacular club usually with carpal (= proximal) locking-apparatus.
- Suckers without circularis muscles (see Sepioidea page).
- Buccal crown
- Buccal supports lack suckers.
- Head
- Head without tentacle pockets.
- Eyes without corneal membranes covering lenses.
- Funnel
- Funnel without lateral adductor muscles. [The more superficial lateral-adductor muscles of sepioids should not to be confused with the external-adductor muscles of the Ommastrephidae.]
- Mantle
- Mantle locking-apparatus, with rare exceptions, reaches anterior mantle margin.
- Fins
- Fins usually joined posteriorly and usually without posterior lobes.
- Shell
- Shell a gladius.
- Viscera
- Gills with branchial canal.
- Oviducts paired.
- Females without accessory nidamental glands.
- Eggs
- Eggs, where known, in pelagic egg masses or egg strings.
Figure. Oral view of the club base of Cycloteuthis serventyi. The red line encircles the suckers and knobs of the carpal locking-apparatus. Drawing modified from Young and Roper (1969).
Comments
Comparisons of the major groups of the Oegopsida CHARACTER TAXA | Buccal connective attachment to arms IV | Funnel-mantle lock; reaches anterior mantle margin | Carpal locking-apparatus present | Gladius conus type |
Architeuthid families | Dorsal | Straight; yes | Yes | Primary |
Brachioteuthidae | Ventral | Straight; yes | Yes/No | Secondary |
Chiroteuthid families | Ventral | Variable, usually oval, often with knobs; yes?? | No | Secondary |
Cranchiidae | Ventral | Fused; yes | Yes | Secondary/ pseudoconus/ no conus |
Cycloteuthidae | Ventral | Triangular; no | Yes | Secondary/no conus |
Enoploteuthid families | Dorsal | Straight; yes | Yes | Primary |
Gonatidae | Ventral | Straight; yes | Yes | Primary |
Histioteuthidae families | Dorsal | Straight; yes | Yes | No conus; cupped coil |
Lepidoteuthidae families | Ventral | Straight; yes | NA/No | Secondary |
Ommastrephidae | Dorsal | Inverted-T; yes | Yes/No | Primary |
Onychoteuthidae | Ventral | Straight; yes | Yes | Primary |
Thysanoteuthidae | Ventral | Lazy-T; yes | Yes | Primary in very young only; no conus |
About This Page
University of Hawaii, Honolulu, HI, USA
National Museum of Natural History, Washington, D. C. , USA
Page copyright © 2019 and
Page: Tree of Life Oegopsida Authored by . Richard E. Young and Michael Vecchione. The TEXT of this page is licensed under the Creative Commons Attribution-NonCommercial License - Version 3.0. Note that images and other media featured on this page are each governed by their own license, and they may or may not be available for reuse. Click on an image or a media link to access the media data window, which provides the relevant licensing information. For the general terms and conditions of ToL material reuse and redistribution, please see the Tree of Life Copyright Policies.
- First online 18 August 2004
- Content changed 26 March 2019
Citing this page:
Young, Richard E. and Michael Vecchione. 2019. Oegopsida http://tolweb.org/Oegopsida/19407/2019.03.26 in The Tree of Life Web Project, http://tolweb.org/
. Version 26 March 2019 (under construction).