Eucyclotoma albomacula


Eucyclotoma albomacula is a species of sea snail, a marine gastropod mollusk in the family Raphitomidae. It was first described by E. Alison Kay in 1979 and is distinguished by a single spiral keel on each whorl with axial white stripes; the species name is derived from the Latin albo and macula.

Description

The shell varies greatly in length, with specimens ranging in size from 2mm to 8mm. The holotype has a diameter of 2mm and a length of about 7.75mm. The shell is tall-spired, thin, with a sloping spiral keel on each whorl. The shell is described as glossy, chestnut brown with three axial streaks of white colour. Its spire consists of a protoconch of two and a half whorls, a teleoconch of c. nine whorls, and an indistinct suture marked by a spiral head and a linear spiral of white and brown. It has a widely oval aperture about one-fifth the total length of the shell, a thin outer lip with protrusions of the spiral keels.

Distribution

Eucyclotoma albomacula are rare, found at mesophotic depths between 59m to 195m. They are thought to be endemic to the Hawaiian Islands. The holotype was collected at a depth of 60m, in Kepuhi Point, O'ahu. Specimens have been collected from Lāna'i, Ni'ihau, French Frigate Shoals, Laysan, Salmon Bank, Pearl and Hermes Atoll, Midway Atoll, and Kure Atoll.
Specimens at Bernice P. Bishop MuseumShell length Site collectedDepth range
17.75Kepuhi Point, O’ahi60m
3specimens3.9-6.0Lāna‘i75m-91m
1specimen4.6Ni‘ihau59m
1specimen7.0French Frigate Shoals85m
1specimen2.5Laysan64m
2specimens, 1partial shell2.7-3.5Salmon Bank82m
12specimens, 1partial shell2.2-3.0Pearl and Hermes Atoll55m-98m
7specimens, 1partial shell2.2-5.7Midway Atoll59m-65m
4specimens2.0-6.8Kure Atoll88m-94m

This table does not represent every specimen of Eucyclotoma albomacula collected, merely specimens in possession of the Bernice P. Bishop Museum, Honolulu, Hawaii.