Bornella pele Pola, Rudman & Gosliner, 2009

ホムラユビウミウシ Bornella pele
Photographed by
KIMOTO Nobuhiko
Location
Nazumado, Hachijo Island, Tokyo, Japan
Date
2019/05/05
Length
??mm
Depth
??m
Water temperature
20.0℃

MORPHOLOGY

The general body shape is elongate and limaciform with the posterior end of the foot being long and tapering. The living adults are small, up to 20 mm in length. The general color pattern consists of a translucent whitish body with scattered subepithelial opaque white granules (Fig. 16A). There are two parallel red marks on the inner side of each dorsolateral process and of the rhinophore sheaths. There is also a pair of red marks on the head running between the oral tentacles and the base of the rhinophore sheaths. Another irregular, elongate red patch runs along the dorsal midline, from behind the last pair of dorsolateral processes to the posterior tip of the foot (Figs. 16A,B). On either side of the mouth is a lobe-like oral tentacle, each bearing 9 to 13 finger-like papillae of unequal length arranged in three different rows. Usually the outer row bears seven papillae. The oral tentacles do not have any red pigmentation. Each rhinophore sheath has a tall stalk from which the rhinophore protrudes. The translucent whitish rhinophores are perfoliated with about 15 to 19 lamellae. Surrounding the upper edge of the rhinophore sheath, are three elongate anterior and anterolateral papillae and a taller, posterior papilla, which is distinctly bifid (Fig. 16B). Posterior to the rhinophores, there are three pairs of dorsolateral processes, followed by two single processes along the dorsal midline (Fig. 16A). The number of processes was consistent in all specimens examined. Each dorsolateral process has a stout base topped with three papillae, all acutely pointed at the tip. The central papilla is larger and more elongate than the other two. There are two bipinnate translucent gills on each of the paired dorsolateral processes. They are located on the inner surface, at the base of the lateral papillae. The bases of the most posterior pair of dorsolateral processes are joined. The two posterior, single, dorsal processes are simple and decrease in size towards the posterior end of the foot. The anus is small, located on the right side of the dorsum between the first and second pair of dorsolateral processes, closer to the second. The reproductive opening is located on the right side, midway between the rhinophore sheath and the first dorsolateral process.

DISTRIBUTION

Thus far this species is known from Hawaii, eastern Australia (present study), and Japan (present study and Nakano 2004: 211 in part).

ETYMOLOGY

This species is named after the Hawaiian goddess “Pele”, goddess of fire, lightning, dance, volcanoes and violence. This species was first collected in Hawaii and the red markings of the animal remind the fire and violence of the Hawaiian goddess.

References