Source: Wikipedia, the free encyclopedia.
(Redirected from

Aplysia californica
, a typical sea hare displaying inking behavior
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Subclass: Heterobranchia
Infraclass: Euthyneura
Cohort: Tectipleura
Order: Aplysiida
P. Fischer
, 1883
  • Anaspidea
  • Aplysiomorpha


molluscs in the superfamilies Aplysioidea and Akeroidea


rhinophores that project upward from their heads and that somewhat resemble the ears of a hare


Many older textbooks and websites refer to this suborder as "Aplysiida". The original author Paul Henri Fischer described the taxon Aplysiida at unspecified rank above family.[1] In 1925 Johannes Thiele established the taxon Aplysiida as a suborder.

2005 taxonomy

Since the taxon Aplysiida was not based on an existing genus, this name is no longer available according to the rules of the ICZN.[citation needed] Aplysiida has been replaced in the new Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005) by the clade Aplysiomorpha.

The scientific name for the order in which they used to be classified, the Aplysiida, is derived from the Greek for "without a shield" and refers to the lack of the characteristic head shield found in the cephalaspidean opisthobranchs. Many Aplysiidans have only a thin, internal and much-reduced shell with a small mantle cavity; some have no shell at all. All species have a radula and gizzard plates.

2010 taxonomy

Jörger et al. (2010)[2] have moved this taxon (named as Aplysiida) to Euopisthobranchia.

2017 taxonomy

The name "Aplysiomorpha" was preferred by Bouchet and Rocroi (2005) over "Aplysiida Fischer", 1883, but the authors now agree that there is a consistent usage for Aplysiida in the recent literature and that the older name must be preferred.[3]


Sea hares are mostly rather large, bulky creatures when adults. Juveniles are mainly unobserved on the shoreline. The biggest species, Aplysia vaccaria, can reach a length of 75 centimetres (30 in) and a weight of 14 kilograms (31 lb) and is arguably the largest gastropod species.[4]

Sea hares have soft bodies with an internal shell, and like all opisthobranch molluscs, they are


Life habits

Sea hare Dolabella auricularia at Big Island of Hawaii

Sea hares are herbivorous, and are typically found on

rhinophores, which are extremely sensitive chemoreceptors

Their color corresponds with the color of the seaweed they eat: red sea hares have been feeding on red seaweed. This camouflages them from predators. When disturbed, a sea hare can release ink from its ink glands, providing a fluid, smoke-like toxic screen, adversely affecting its predators' olfactory senses while acting as a powerful deterrent. The toxic ink may be white, purple, or red, depending on the pigments in their seaweed food source and lightens in color as it spreads, diluted by seawater. Their skin contains a similar toxin that renders sea hares largely inedible to many predators.[citation needed] In addition to the colored ink, sea hares can secrete a clear slime akin to that released defensively by hagfish which physically plugs the olfactory receptors of predators like lobsters.[6][7]

Some sea hares can employ jet propulsion as a locomotion and others move like stingrays but with greater fluttering fluidity in their jelly-like "wings". In the moving marine environment and without the sophisticated cognitive machinery of the cephalopods, their motion appears to be somewhat erratic, but they do reach their goals, such as the seabed, according to the wave-action, currents, or calmness of their area.[8][9]

Human use

Sea hares are consumed in several parts of the world. An example may be "酱爆海兔"[10] (jiàng bào hǎi tù), lit. "sauce-fried sea hare", a Chinese dish featuring sea hare and occasionally squid quickly fried in a sauce. In

imu wrapped in ti leaves.[citation needed

Nobel Laureate Eric Kandel.[11] Research surrounding the aplysia gill and siphon withdrawal reflex may be of particular interest with respect to this.[12]

Reef aquaria

Sea hares are often used as a method of eradicating nuisance algae and cyanobacteria ("red slime algae") in reef aquaria. The hares usually do an excellent job, but when they have eaten all of the algae and cyanobacteria, they often shrink from starvation and eventually starve to death. Many reef-keeping clubs have started programs where groups of hobbyists "share" a single sea hare among a large group.


  1. ^ Fischer, P. (1883). Manuel de conchyliologie et de paléontologie conchyliologique fasc. 6. Paris: Savy. pp. 513–608.
  2. PMID 20973994
  3. ^ Gofas, S. (2010). Aplysiomorpha. In: MolluscaBase (2017). Accessed through: World Register of Marine Species at marinespecies.org on 2017-03-30
  4. ^ Rudman, W.B.; Firminger, P.I., eds. (15 July 2010). "Aplysia vaccaria". The Sea Slug Forum (seaslugforum.net). New South Wales, AU: Australian Museum.
  5. .
  6. ^ Ceurstemont, Sandrine (2013-03-28). "New Scientist TV: Sea hares use sticky weapon to cripple predators". Retrieved 2016-09-30.
  7. ^ Peterson, Coyote (2016-09-30). "Inked by a Giant Slug! - YouTube". YouTube. Retrieved 2016-09-30.
  8. S2CID 85088231
  9. .
  10. ^ 酱爆海兔的作法
  11. ^ Edythe McNamee and Jacque Wilson (14 May 2013). "A Nobel Prize with help from sea slugs". CNN. Retrieved 2020-10-31.
  12. ^ Agranoff, Bernard W.; Cotman, Carl W.; Uhler, Michael D. (1999). "Invertebrate Learning and Memory". Basic Neurochemistry: Molecular, Cellular and Medical Aspects. 6th Edition.