Tritonia bollandi
Smith & Gosliner, 2003

Order: NUDIBRANCHIA
Suborder: DENDRONOTINA
Family: Tritoniidae

DISTRIBUTION

Known from Okinawa & Indonesia.

PHOTO

Upper & Lower Right: type material on its food, the gorgonian Verrucella aurantia, Seragaki Tombs, Okinawa. Photos: R. Bolland.
Lower Left: Lembeh Strait, Sulawesi, Indonesia. Depth: 7m, 21 November 2001. Length: 50mm. Photo by M. & C. Nishina

Previously known on the Forum as Tritoniid species 8 this species has just been described from Okinawa as Tritonia bollandi in honor of its collector, Robert Bolland. In Okinawa it is found exclusively on its food, the gorgonian Verrucella aurantia (Gray, 1869) [Family Ellisellidae].

The animal reaches 88 mm in length, and mature specimens from the type locality, Okinawa, are olive green in color, with lighter colored branchial plumes, nearly white rhinophores, and a thin white margin along the notal margin. The body appears granular due to the presence of small low tubercles on all parts of the body, except for the foot. The oral veil is slightly bilobed and bears 12 to 14 elongate digitiform processes, many of which are apically bifid. The notal margin extends along and slightly overhangs the sides of the body. From the notal margin are produced 9 to 14 pairs of arborescent branchial plumes, and the sheaths of the rhinophores, whose margins are undulate and flange-like. The rhinophore shafts are retractable, and are palmate in appearance, with a central clavus surrounded by a stepped series of pinnate processes. External genitalia are on the right side of the animal, behind the third anterior branchial plume. The anus and nephroproct are also on the right side, behind and just below the 4th branchial plume, close to the notal margin. The anterior foot margin is rounded. Tritonia bollandi has been observed to feed upon gorgonian octocorals of the family Ellisellidae (Gray, 1859), in particular Verrucella aurantia (Gray, 1869). This nudibranch is named after the collector. Indonesian specimens on the Forum show a slightly different coloration

Reference:
• Smith, V. G. & Gosliner, T. M. (2003) A new species of Tritonia from
Okinawa (Mollusca: Nudibranchia), and its association with a gorgonian octocoral. Proceedings of the California Academy of Sciences, 54 (16): 255-278, 16 figs.

Authorship details
Smith, V. G., 2003 (August 16) Tritonia bollandi Smith & Gosliner, 2003. [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/factsheet/tritboll

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