Palmadusta humphreyii

Lore & Background

The species name humphreyii was originally published with the incorrect spelling humphreysii, an error corrected by Gray himself on the errata page of the same volume of the Journal. This correction is a valid emendation under the International Code of Zoological Nomenclature, though the original incorrect spelling has persisted in some later usage. The shells are quite uncommon and reach an average length of 10 to 25 mm. The dorsum surface is smooth and shiny, colored white or pale pink with many brown spots, while the edges and extremities are orange with darker spots extending to the base. The underside may be orange, pale yellow, pale brown, or pale pink, with a narrow sinuous aperture and well-developed teeth. In living specimens, the mantle is bright red, and both the mantle and foot are well developed, with short papillae and external antennae. This species occurs in shallow water on coral reefs at depths of 5 to 25 mm, typically hiding under coral and rocks, and feeds on algae or coral polyps.

Reader's Guide

Palmadusta humphreyii holds significance as a taxonomically clarified species, with its correct spelling restored through Gray's own errata correction. The species has been subject to taxonomic debate, with some later authors overlooking the errata sheet and perpetuating the incorrect spelling humphreysii. Several subspecies and forms have been proposed: Palmadusta humphreysii humphreisii is accepted as an alternate representation; Palmadusta humphreysii yaloka is considered a synonym; and Palmadusta humphreysii f. 'coccinella' is a synonym of Palmadusta johnsonorum. The species is endemic to a broad range spanning East Africa and the Western Pacific, including Malaysia, Queensland, New South Wales, Papua New Guinea, New Caledonia, the Solomon Islands, Tonga, and Fiji. Its variable coloration and pattern, combined with its relatively uncommon status, make it a notable cowrie among collectors. The species' habitat preferences—shallow coral reefs where it hides under coral and rocks—and its diet of algae or coral polyps place it within the typical ecological niche of many cowries.

Did You Know?

• The original spelling humphreysii was an error corrected by Gray on the errata page of the same volume.
• The correct spelling humphreyii was restored under I.C.Z.N. Article 32.5.1.1.
• The living cowrie has a bright red mantle and well-developed foot with short papillae.
• This species is endemic to East Africa and the Western Pacific Ocean.