Aplysia juliana
Quoy & Gaimard, 1832

Superfamily: APLYSIOIDEA
Family: Aplysiidae


Circumglobal - found in all warm water regions of the world.


UPPER: Long Reef, Collaroy, Sydney, NSW, in algal tide pools, ranging in length from 20-45mm. September 1978.
MIDDLE, LOWER: Port Stephens, New South Wales, Australia, 78mm long. October 1980.
PHOTOS: Bill Rudman.

Aplysia juliana is one of the few species of Aplysia that lacks the ink gland which produces the characteristic reddish purple ink. Instead the opaline gland, produces a milky white secretion. All aplysiids have an opaline gland, but the milky white secretion is usually marked by the purple ink. Aplysia juliana is also unusual in that the posterior end of the foot can form a temporary sucker. When the animal crawls along it can use the sucker to anchor itself then greatly extend its head and neck like a leech. Another aplysiid that does this is Dolabrifera dolabrifera.

There are quite a few colour forms of this species which are at present unable to be separated on anatomical grounds. the brownish form with pale spots (top photo) is one of the most common forms, as is one with a uniform black colouration. The other photos here represent a colour form associated with Bergh's Aplysia sibogae, which is considered a synonym.

See the General Topics List for more information on Sea Hares.

• Quoy, J.R. & Gaimard, J.P. (1832). Voyage de decouvertes de L'Astrolabe pendant les annees 1826-1827-1828-1829, sous le commandement de M.J. Dumont D'Urville, Zoologie, 2: 1-686.

Authorship details
Rudman, W.B., 1999 (May 3) Aplysia juliana Quoy & Gaimard, 1832. [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/factsheet/aplyjuli

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