tritoniid nudibranch Tritonia challengeriana

Tritonia challengeriana is found in Antarctica and the Antarctic Peninsula, South Shetland Islands, South Georgia Island, Falkland Islands, Bouvet Island, and southern Chile and Argentina, at depths from 1 to 481 meters [1,2,3,4,5]. In one study, T. challengeriana was studied at depths from 5 to 36 meters and was most abundant around 7 meters in red algae communities [1]. Specimens of T. challengeriana have been recorded at lengths up to 6.5 centimeters [2,4].

Here T. challengeriana is perched on the soft coral Alcyonium antarcticum. The two white spots on the right side of the body are the genital (upper) and anal (lower) openings [2].



The color of Tritonia challengeriana is milky white to transparent, sometimes yellowish to brownish, with yellowish or rose colored viscera shining through the body wall [2]. White pigment is present on the gills, notal margin, rhinophore tips and sheath margins, velar tentacles, and papillae of the oral veil [2]. Small white stripes radiate across the notum from the bases of gills [2].



Zooids of Cephalodiscus were observed in the digestive tract of one specimen of Tritonia challengeriana [2]. Cephalodiscus is a worm-like invertebrate (pterobranch hemichordate) living in secreted tubes organized into a colonial structure.

Taxonomic Note: An older name Tritonia antarctica is a synonym of Tritonia challengeriana [4]

1: Journal of Molluscan Studies 62(3):281-287, 1996; 2: Zoological Journal pf the Linnean Society of London 113(1):21-46, 1995; 3: Polar Biology 24(2):105-112, 2001; 4: Sea slugs of southern South America: systematics, biogeography and biology of Chilean and Magellanic Nudipleura (Mollusca, Opisthobranchia). Michael Schrödl. Hackenheim, Germany: ConchBooks, 2003; 5: Polar Biology 29(2):128-136, 2006

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