Eatoniella albocolumella

Eatoniella albocolumella
Holotype of Eatoniella albocolumella from Auckland War Memorial Museum
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Subclass:	Caenogastropoda
Order:	Littorinimorpha
Superfamily:	Cingulopsoidea
Family:	Eatoniellidae
Genus:	Eatoniella
Species:	E. albocolumella
Binomial name
Eatoniella albocolumella Ponder, 1965
Synonyms
Eatoniella (Abscindostoma) albocolumellaPonder, 1965

Eatoniella albocolumella is a species of marine gastropod mollusc in the family Eatoniellidae. ^[1] It was first described by Winston Ponder in 1965. It is endemic to New Zealand, found in the waters of the North Island, northern and eastern coasts of the South Island, and in the Chatham Islands.

Description

Type specimen collected in Lyall Bay, Wellington

In the original description, Ponder described the species as follows:

Shell small, thin, semi-transparent, smooth, shining, imperforate variably coloured. Spire tall, conical, with straight outlines; whorls 5, lightly convex, false margined; protoconch moderately large, smooth, of similar colour to spire whorls, not distinctly marked off; body whorl with a rounded periphery and base. Aperture moderately large, oval; peristome continuous, weakly thickened; outer lip sharp, thickened! a little posteriorly and internally, strongly and broadly excavated. Inner lip evenly concave and produced a little below. A narrow groove in umbilical region, but no umbilicus. Colour variable, usually dark purplish grey, sometimes uniform as in the holotype, except for the lower part of the base and columella which are always white. Usually with a series of irregular white blotches below sutures and/or on periphery, these frequently becoming broadly developed as irregular white zig-zag markings. There is great variation within populations, all intergradations between nearly pure white shells and uniform dark shells occur. ^[2]

The species' animal has long cephalic tentacles, is colourless, and has a short, blobed snout with an orange buccal mass. The operculum is oval, curved and yellow. ^[2] E. albocolumella measures 2.37 mm (0.093 in) by 1.35 mm (0.053 in). ^[3] The species' colour pattern is highly variable, ^[4] and is typically dark purple-grey, except for the white lower base and columella. ^[5]

The species resembles E. limbata , but can be distinguished due to the thin shell and strongly reflected outer lip of E. albocolumella, and due to E. albocolumella having more irregular markings and a white umbilical region. ^[2] It has a similar shape to E. lutea , but can be distinguished due to being smaller, and due to E. lutea having a more consistent colour pattern across individuals. ^[5]

Taxonomy

The species was first described by Winston Ponder in 1965, who used the name Eatoniella (Abscindostoma) albocolumella. ^[2] The modern formatting of the name without a subgenus, Eatoniella albocolumella, was established by Hamish Spencer and Richard C. Willan in 1995. ^{[6] [7]} The holotype of the species was collected by W.J. Ballantine on 16 February 1964, on coralline algae at Cape Campbell in the Marlborough District of the South Island of New Zealand. It is held by the Auckland War Memorial Museum. ^{[8] [9]}

Distribution and habitat

The species is Endemic to New Zealand, ^[1] found in the waters of the North Island, Chatham Islands, and the northern and eastern coasts of the South Island. ^{[2] [3]} E. albocolumella is one of the most commonly found micromolluscs in the Kawhia Harbour. ^[10]

The species is often found living on the surface of seaweeds, ^[10] including low tide seaweeds, ^[11] and is often abundantly found on coralline algae and short turf algae on exposed coasts, and more rarely under stones or on moderately exposed brown algae. ^[2]

References

1. Eatoniella albocolumella Ponder, 1965 . Retrieved through: World Register of Marine Species  on 9 December 2025.
2. Ponder, W. F. (1965). "The Family Eatoniellidae in New Zealand". Records of the Auckland Institute and Museum . 6: 47–99. ISSN   0067-0464. JSTOR   42906115. Wikidata   Q58676802.
3. "Eatoniella albocolumella". New Zealand Mollusca. Retrieved 20 November 2022.
4. Morley, Margaret S.; Hayward, Bruce W. (2010). "Tidal Zonation of Ostracod and Micromolluscan Faunas in Coralline Turf on the East and West Coasts of Auckland, New Zealand" (PDF). Papahou: Records of the Auckland Museum . 47: 51–74. ISSN   1174-9202. JSTOR   42905912. Wikidata   Q58623372.
5. Powell, A.W.B. (1979). New Zealand Mollusca: Marine, Land and Freshwater Shells. Auckland: Collins. p. 90. ISBN   0002169061.
6. Spencer, H. G.; Willan, R. C. (1995). "The marine fauna of New Zealand: Index to the fauna. 3. Mollusca" (PDF). New Zealand Oceanographic Institute Memoir. 105: 1–125. ISSN   0083-7903. Wikidata   Q66411987.
7. Morley, Margaret S. (April 1997). "New Zealand Mollusc Name Changes from Powell (1979) to Spencer & Willan (1996)". Poirieria. 20: 13–22.
8. Blom, Wilma M. (2025). "Annotated Catalogue of Fossil and Extant Molluscan Types in the Auckland War Memorial Museum". Bulletin of the Auckland Museum . 22. doi:10.32912/BULLETIN/22. ISSN   1176-3213. OCLC   1550165130. Wikidata   Q135397912.
9. "Eatoniella albocolumella". Collections Online. Auckland War Memorial Museum . Retrieved 9 December 2025.
10. Morley, Margaret S.; Hayward, Bruce W.; Stephenson, A. Brett (1997). "Molluscs, crustacea and echinoderms from Kawhia, west coast, North Island". Tane. 35: 157–180.
11. Hayward, Bruce; Morley, Margaret (2004). "Intertidal Life Around the Coast of the Waitakere Ranges, Auckland" (PDF). Auckland Regional Council . Retrieved 24 November 2025.