Aplysia

gastropod genus

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June 18, 2026

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The genus Aplysia refers to marine gastropod mollusks commonly known as sea hares. These animals are characterized by a reduced shell, prominent tentacles resembling rabbit ears, and a smooth or warty body. Sea hares primarily consume large seaweeds and are simultaneous hermaphrodites. When threatened, they can discharge a purple ink. Species within this genus, such as Aplysia dactylomela, are found in various marine environments. Research on Aplysia has significantly contributed to the scientific understanding of the biochemical basis of learning.12

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mollusk
Features of defense
…from the sea hare (Aplysia; a gastropod of the subclass Opisthobranchia) distract and confuse the predator and conceal the prey. Camouflage or frightening coloration are effective in protecting cuttlefishes, octopuses, and sea slugs, as well as other gastropods.
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…from the sea hare (Aplysia; a gastropod of the subclass Opisthobranchia) distract and confuse the predator and conceal the prey. Camouflage or frightening coloration are effective in protecting cuttlefishes, octopuses, and sea slugs, as well as other gastropods.
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gastropod
Food and feeding
Besides the algae-sucking sacoglossans, Aplysia cuts up strips of seaweed for swallowing, and a number of the more primitive species feed on algae encrusted on rocks. Perhaps the majority of opisthobranchs, including the sea slugs, are predators on sessile animals, ascidians and coelenterates being especially favoured. Pyramidellids are ectoparasites…
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Besides the algae-sucking sacoglossans, Aplysia cuts up strips of seaweed for swallowing, and a number of the more primitive species feed on algae encrusted on rocks. Perhaps the majority of opisthobranchs, including the sea slugs, are predators on sessile animals, ascidians and coelenterates being especially favoured. Pyramidellids are ectoparasites…
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animal learning
Habituation
…example, in the sea snail Aplysia—has confirmed that habituation need not depend on changes in the activity of sensory or motor neurons. In the case of Aplysia, researchers have studied the gill withdrawal reflex, a response that rapidly habituates to repeated stimulation of the snail’s siphon or mantle shelf. But…
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…example, in the sea snail Aplysia—has confirmed that habituation need not depend on changes in the activity of sensory or motor neurons. In the case of Aplysia, researchers have studied the gill withdrawal reflex, a response that rapidly habituates to repeated stimulation of the snail’s siphon or mantle shelf. But…
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