Oegopsida

cephalopod suborder

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July 1, 2026

Quick Summary

The Oegopsida are a suborder of squid, which are marine cephalopods with ten arms. These squid are characterized by their open eyes, which are not covered by a transparent membrane, and they inhabit open ocean environments from the surface down to at least 3,000 meters.12

Squid have streamlined bodies and complex eyes. They possess eight arms and two longer tentacles, which are used for capturing prey. Internally, most squid have a flexible shell called a gladius. They are a significant food source for many marine animals, including sperm whales and fish.1

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cephalopod
Annotated classification
Suborder Oegopsida Eye open to water, completely surrounded by free eyelid; open-ocean animals living from the surface down to at least 3,000 m. Order Vampyromorpha Purplish-black gelatinous animals with 1 or 2 pairs of paddle-shaped fins at various stages of growth; 8 arms and 2 small…
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Suborder Oegopsida Eye open to water, completely surrounded by free eyelid; open-ocean animals living from the surface down to at least 3,000 m. Order Vampyromorpha Purplish-black gelatinous animals with 1 or 2 pairs of paddle-shaped fins at various stages of growth; 8 arms and 2 small…
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bioluminescence
The range and variety of bioluminescent organisms
Of the open-ocean squids (oegopsids) such as Lycoteuthis, Histioteuthis, and Enoploteuthis, as many as 75 percent are self-luminous; i.e., light results not from symbiotic luminous bacteria but from an internal biochemical reaction. In deep-sea squids, the light organ is often found on the eyelid or on the eyeball itself.…
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Of the open-ocean squids (oegopsids) such as Lycoteuthis, Histioteuthis, and Enoploteuthis, as many as 75 percent are self-luminous; i.e., light results not from symbiotic luminous bacteria but from an internal biochemical reaction. In deep-sea squids, the light organ is often found on the eyelid or on the eyeball itself.…
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mollusk
Reproduction and life cycles
Squids of the suborder Oegopsida and some gastropods have eggs that are suspended in the water. Fertilized eggs commonly undergo spiral cleavage, as in annelids and a number of other “protostome” phyla. The eggs of cephalopods, on the other hand, possess a large amount of yolk, which displaces the…
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Squids of the suborder Oegopsida and some gastropods have eggs that are suspended in the water. Fertilized eggs commonly undergo spiral cleavage, as in annelids and a number of other “protostome” phyla. The eggs of cephalopods, on the other hand, possess a large amount of yolk, which displaces the…
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