Trapania kamagong Smirnoff, Donohoo & Gosliner, 2022

トラパニア・カマゴン Trapania kamagong
Photographed by
IMAGAWA 今川郁
Location
Red Beach, Hontou (East coast), Okinawa, Japan
Date
2007/01/18
Length
8mm
Depth
13.0m
Water temperature
20.0℃

MORPHOLOGY

It has an opaque grey body covered dorsally with speckled red-brown colour characterized by small and large blotches of missing pigmentation. Notable blotches reside laterally below the rhinophores, below the gill plum and at the posterior portion of the foot. Extra-rhinophoral and extra-branchial appendages lack coloration from base to the tip, which has the same red-brown coloration as the body. Rhinophores, eight to ten lamellae and a pointed tip, are uniformly wide along their length and the same colour as the red-brown body, except for grey tip. Oral tentacles are coloured at their base and opaque grey at the tip. Similarly, the anterior margins of the foot, which extend laterally as elongate appendages, are coloured at their base and opaque grey at their tip. The gill plum is prominent and a lighter brown than the body. Buccal mass: The buccal mass is muscular with a moderately enlarged buccal pump on the dorsal surface. Inside the anterior portion of the mass is a pair of well-developed jaws. The jaws contain a row of acutely pointed and stubby jaw elements of various sizes that are tightly packed together with a few gaps between them (Fig. 17A). The radular formula of the holotype is 23 × 1.0.1. The older teeth are much smaller (Fig. 17B) than the newer ones (Figs. 17C, D) and the radula widens gradually towards the more newly developed teeth. The teeth bear numerous denticles with the smallest ones being found on the inner edge of the tooth. There are approximately four to 15 denticles on the inner side of the much larger primary cusp, and one to two denticles on the outer side of the cusp. The older teeth have fewer denticles than the more recently developed ones.

DISTRIBUTION

Known only from the Philippines.

ETYMOLOGY

Kamagong is the Tagalog name for the velvet apple, Diospyros discolor Willd. (Ebenaceae), a species of persimmon tree found in the Philippines and Taiwan. It refers to the distinguishing dark-tipped, extra-rhinophoral and extra-branchial appendages of this species.

References