Tritoniella

Tritoniella
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Subclass:	Heterobranchia
Order:	Nudibranchia
Suborder:	Cladobranchia
Family:	Tritoniidae
Genus:	Tritoniella Eliot, 1907[1]
Type species
Tritoniella belli Eliot, 1907
Species
T. belli T. gnocchi T. prinzess T. gnathodentata T. schoriesi T. heideae

Tritoniella is a

Tritoniella can be differentiated from Tritonia (the only other Tritoniidae sharing its distribution range) by a wide dorsal ridge and lack of foliaceous tufts (gills).^[2]

It can grow to a length of up to 8 cm (3 in). Most individuals have a ridge running along the middle of the back. The colour is variable, ranging from a translucent milky white to yellow or orange.^[3]

Distribution

Tritoniella can be found in the Southern Ocean around the coast of Antarctica and along the Scotia Arc up north to Burdwood Bank south of the Falkland Islands at depths between 5 m (20 ft) and 751 m (2,500 ft).^[3][2]

Ecology

Tritoniella feeds mainly on soft corals,^[2] but may also feed on hydroids and sea anemones.^[3]

Tritoniella belli incorporates the chimyl alcohol ingested from Clavularia frankliniana into its tissue to use it as a chemical defence to make itself upalatable against predators.^[3]

It is avoided by the predatory starfishes Odontaster validus, Perknaster fuscus and Acodontaster conspicuus because the mucus it extrudes is distasteful; it is preyed on by the sea anemone Isotealia antarctica, but 70% of the encounters between the two result in the nudibranch escaping, or the sea anemone swallowing the nudibranch but then regurgitating it from its gastrovascular cavity.^[4] The gelatinous egg ribbons of the nudibranch are also eaten by I. antarctica but rejected by O. validus.^[5]

References