Marionia distincta Bergh, 1905
Some of the most interesting and odd shaped opisthobranch beasts are the members of the Dendronotacea, particularly members of the tritonid genera Marionia and Tritonia. The Indo-Pacific is home to numerous undescribed species of the genus Marionia, the systematics of which is poorly known. The two genera are separated by the presence of chitinous plates in the stomach of species of Marionia. This major internal difference is of little value to divers and photographers who happen upon the diversely appointed members of these genera, and has led to confusion in the popular literature, where species have been placed in one or the other genus incorrectly.
Marionia distincta is one of the easiest to identify because of the series of thin brown lines that transverse the dorsal surface between "cerata-like" appendages. The rhinophores are typically fluted. Specimens may reach 60 mm in length.
Species of both Marionia and Tritonia feed on soft corals, xeniids particularly. This species has not been found in association with any particular soft coral species, but is common in shallow reef communities where xeniid soft corals are dominant.
Taxonomic information courtesy of Dave Behrens
Photograph courtesy of Terry Gosliner
David W. Behrens
Pacific Coast Nudibranchs
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