Alvania maclurgi

Alvania maclurgi
Holotype from the Auckland War Memorial Museum
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Subclass:	Caenogastropoda
Order:	Littorinimorpha
Superfamily:	Rissooidea
Family:	Rissoidae
Genus:	Alvania
Species:	A. maclurgi
Binomial name
Alvania maclurgi (A. W. B. Powell, 1933)
Synonyms [1]
Alvania (Linemera) maclurgi(A. W. B. Powell, 1933) Alvinia (Linemera) maclurgi(A. W. B. Powell, 1933) Linemera maclurgiA. W. B. Powell, 1933

Alvania maclurgi is a species of marine gastropod mollusc in the family Rissoidae. ^[1] Endemic to New Zealand, the species is found in the waters of the Chatham Islands, Bounty Islands, and on the Mernoo Bank.

Description

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

Shell small, elongate-ovate, moderately solid, white. Whorls 5, including a prominent protoconch of two globose, smooth whorls. Post-nuclear sculpture of prominent axials, crossed by less prominent spirals. The points of intersection are raised into rounded gemmules. There are seventeen axials on the penultimate and nineteen on the body-whorl, and the interspaces are a little wider than the width of the axials. The spiral cords are few, only two on the spire whorls, with a third developing from the lower suture on the body-whorl, and two more on the base. Spire tall, about one and two-thirds height of aperture. Aperture ovate. Peristome continuous, not variced. There is a long crescentic umbilical chink, and this is bordered by the lower of the two basal spirals. ^[2]

The species measures 1.8 mm (0.071 in) by 1.05 mm (0.041 in). ^[3] It can be identified due to its smaller number of spiral chords. ^[2]

Taxonomy

The species was first described by A. W. B. Powell in 1933, who used the name Linemera maclurgi. ^[2] Powell named the species after Tom MacClurg, the owner of the launch who assisted in the dredging operation that led to the discovery of the holotype. ^[2] In 1985, Winston Ponder recombined Linemera as a subgenus of Alvania, leading to the species' name becoming Alvania (Linemera) maclurgi. ^[4] The representation Alvania maclurgi without a subgenus is the currently accepted name. ^[1]

The holotype was collected in February 1933 by either A.W.B. Powell and/or C.A. Fleming off the coast of Owenga Beach, Chatham Islands, at a depth of 18 m (59 ft). The holotype is held by the Auckland War Memorial Museum. ^{[5] [6]}

Distribution and habitat

The species is endemic to New Zealand, found in the waters of the Chatham Islands, ^[7] Bounty Islands, and on Mernoo Bank, at a depth of between 15–165 m (49–541 ft). ^[3]

References

1. Alvania maclurgi (A. W. B. Powell, 1933) . Retrieved through: World Register of Marine Species  on 9 December 2025.
2. Powell, A. W. B. (1933). "The Marine Mollusca of the Chatham Islands". Records of the Auckland Institute and Museum . 1: 181–208. ISSN   0067-0464. JSTOR   42905950. Wikidata   Q58676558.
3. "Alvania maclurgi". New Zealand Mollusca. Retrieved 9 December 2025.
4. Ponder, Winston F. (12 February 1985). "A review of the genera of the Rissoidae (Mollusca: Mesogastropoda: Rissoacea)". Records of the Australian Museum, Supplements. 4: 1–221. doi:10.3853/J.0812-7387.4.1985.100. ISSN   0812-7387. Wikidata   Q99966349.
5. 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.
6. "Alvania (Linemera) maclurgi". Collections Online. Auckland War Memorial Museum . Retrieved 9 December 2025.
7. Dell, R. K.; Edmonds, S. J. (1961). "Biological results of the Chatham Islands 1954 Expedition. Part 4. Marine Mollusca; Sipunculoidea" (PDF). New Zealand Oceanographic Institute Memoir. 7: 1–27. ISSN   0083-7903. Wikidata   Q66412133.

Further reading

• Powell, A.W.B. (1979). New Zealand Mollusca: Marine, Land and Freshwater Shells. Auckland: Collins. ISBN   0002169061.
• Spencer, H.G., Marshall, B.A. & Willan, R.C. (2009). Checklist of New Zealand living Mollusca. pp 196–219. in: Gordon, D.P. (ed.) New Zealand inventory of biodiversity. Volume one. Kingdom Animalia: Radiata, Lophotrochozoa, Deuterostomia. Canterbury University Press, Christchurch.