Bornella stellifera (A. Adams & Reeve, 1848)

Location: Makiminato, Okinawa Island (Chatan and Southern area), Okinawa, Japan
Date: 2015/04/19
Length: 30mm
Depth: 3.0m
Water temperature: 22.0℃

Description

The body is elongate and limaciform, with the posterior end of the foot long and tapering. Living adults reach about 48 mm in length. The ground colour is translucent cream-white with a network of orange markings on the back and sides and scattered subepidermal opaque white granules; this colour pattern extends to the rhinophore sheaths. The lobe-like oral tentacles, rhinophoral papillae and dorsolateral processes are translucent white with a subapical orange ring. Each lobe-like oral tentacle bears up to 13 finger-like papillae of unequal length, arranged in two distinct marginal rows. The rhinophores are perfoliate with about 13 to 20 translucent white lamellae. Each rhinophore sheath has a tall stalk that branches distally into three elongate anterior and antero-lateral papillae and one posterior, slightly compressed and unbranched papilla, about twice the height of the others. Behind the rhinophores there are five to six pairs of dorsolateral processes, followed by two small unpaired processes along the dorsal midline. The first four pairs bear translucent tripinnate gills on their inner surface; the fifth pair (and sixth when present) and the unpaired posterior processes lack gills.
The buccal bulb is relatively small and the labial cuticle is thin, made of small overlapping scales. The rachidian teeth are stout, each with about seven to ten denticles on either side of a pointed cusp. The posterior chamber of the stomach is elongate and armed with about 12 to 15 longitudinal rows of acutely pointed chitinous spines. The penis bears more than two circular rows of chitinous hooked spines around the penial opening — a feature unique to this species within the genus.

Distribution

Widely distributed across the Indo-West Pacific. The type locality is the South China Sea. Recorded from Australia, Korea, the Philippines, Taiwan, Thailand, Malaysia, Indonesia, Papua New Guinea, New Caledonia, Fiji, Samoa, the Marshall Islands, Hawaii, Tahiti, East Africa, South Africa, Madagascar, the Red Sea region, and the Indian Ocean.

Etymology

The Latin specific epithet stellifera means "star-bearing", referring to the scattered white star-like granules on the dorsum. The genus Bornella is feminine, so the feminine ending stellifera is the grammatically correct form, although the masculine spelling stellifer is widely used in the original description and subsequent literature.

Remarks

This species has a complicated nomenclatural history, reviewed by Bertsch 1980 and Rudman 1984, who established Bornella stellifera (also spelled B. stellifer) as the correct name for the type species. Pola, Rudman & Gosliner 2009 further synonymised Bornella hancockana Kelaart, 1859, B. arborescens Pease, 1871, B. caledonica Crosse, 1875a and B. marmorata Collingwood, 1881 with this species, and treated Bornella semperi Crosse, 1875b as a nomen nudum. The species feeds on hydroids.
Bornella stellifera can be distinguished from the very similar Bornella hermanni by the presence of orange subapical rings on the papillae of the rhinophore sheaths and dorsolateral processes, by having five to six pairs of dorsolateral processes, and by the simple, unbranched posterior papilla on the rhinophore sheath.

Photographed by 今川郁

Description

Distribution

Etymology

Remarks

References

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Seasonality

Shooting Locations

Photos of Bornella stellifera

Same Genus Nudibranchs

Similar Colors Nudibranchs

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