Anatoma equatoria

Anatoma equatoria
Shell of Anatoma equatoria (specimen at the Natural History Museum Rotterdam)
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Subclass:	Vetigastropoda
Order:	Lepetellida
Superfamily:	Scissurelloidea
Family:	Anatomidae
Genus:	Anatoma
Species:	A. equatoria
Binomial name
Anatoma equatoria (Hedley, 1899)
Synonyms [1]
Anatoma aequatorinaHedley, 1899 Anatoma lamellata nanshaensisFeng, 1996 Scissurella equatoriaHedley, 1899

Anatoma equatoria is classified as a species of small sea snail, belonging to the family Anatomidae. It represents a marine gastropod mollusk, often categorized as a micromollusk due to its size. ^[1]

Description

The length of the shell attains 2.68 mm, its diameter 3mm.

(Original description) The shell is notably large for the genus, thin, and trochiform, featuring a gradate spire. It displays frilled, projecting keels and a compressed belt below the fasciole, which leads to a tumid base. The shell is entirely white.

It comprises five whorls. The sculpture consists of approximately eighty-five curved, oblique, and lamellate ribs that traverse the entire shell. Above, the spiral sculpture is barely traceable, but on the base, it becomes distinguishable as delicate, widely spaced threads that override the ribs and create a latticework in the interspaces. The fasciole is enfolded by broad margins, which are fimbriated by the ribs. The umbilicus is narrow, infundibuliform, and deep. The aperture is oblique and subquadrate. The outer lip is slightly and gently recurved, while the columellar margin is explanate and extends over the umbilicus. ^[2]

Distribution

This species occurs in the Java Sea, Indonesia; also in the Indo-Malayan Archipelago to mid-western Pacific; also off Australia and northern New Zealand and on the Kermadec Ridge.

References

1. WoRMS (2012). Anatoma equatoria (Hedley, 1899). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=492963 on 2013-02-16
2. Hedley, C. (1899). "The Mollusca of Funafuti. (Supplement)". Memoirs of the Australian Museum. 3: 551. Retrieved 19 July 2025.

• Habe, T. & Kosuge, S. 1964. List of the indo-Pacific Mollusca concerning to the Japanese Fauna. Bulletin of the National Science Museum, Tokyo 8
• Feng W.-M. [Weimin]. (1996). Microgastropods from Nansha sea area, China. In: Studies on marine fauna and flora and biogeography of the Nansha Islands and neighbouring waters II: 85-205.
• Geiger D.L. (2012) Monograph of the little slit shells. Volume 1. Introduction, Scissurellidae. pp. 1-728. Volume 2. Anatomidae, Larocheidae, Depressizonidae, Sutilizonidae, Temnocinclidae. pp. 729–1291. Santa Barbara Museum of Natural History Monographs Number 7.

External links

• Helwerda R.A. & Wesselingh F.P. (2014). "Revision of Scissurellidae, Anatomidae and Fissurellidae (Gastropoda: Vetigastropoda) from the Plio-Pleistocene of the Philippines". Zootaxa. 3838 (2): 183–194.
• Encyclopedia of Life
• World Register of Marine Species