Amastra magna

Amastra magna
	Shell of Amastra magna
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Order:	Stylommatophora
Family:	Amastridae
Genus:	Amastra
Species:	A. magna
Binomial name
	Amastra magna; (C. B. Adams, 1851)
Synonyms
	Achatinella baldwinii Newcomb, 1854 junior subjective synonym; Achatinella gigantea Newcomb, 1854 junior subjective synonym; Achatinella magna C. B. Adams, 1851 (original combination); Amastra (Amastra) magna C. B. Adams, 1851 alternative representation;

Amastra magna is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusc in the family Amastridae.^[1]

Subspecies

Amastra magna balteata Hyatt & Pilsbry, 1911
Amastra magna magna (C. B. Adams, 1851)

Description

The shell is robust, ovate-conic, and elongate, with a distinct coloration: blackish-brown at the apex, transitioning to reddish-brown on the middle whorls, and ash-colored on the lower whorls. Its surface is adorned with irregular, coarse, and unequal transverse striae, accompanied by closely spaced, arcuate ribs near the apex. Indistinct raised spiral lines are present on the lower portion of the body whorl.

The apex is subacute, and the spire is relatively long, featuring gracefully curvilinear outlines. The shell is composed of seven slightly convex whorls with a well-defined, deeply impressed suture. The body whorl is obtusely angular.

The aperture is ovate and sharply acute at the upper end, with an extremely thickened deposit along the inner margin. A prominent, large, and compressed columellar fold adds to the distinctive morphology. ^[2]

Distribution

This species is endemic to Hawaii, occurring on Lanai Island.

References

^ Amastra magna (C. B. Adams, 1851). 24 December 2024. Retrieved through: World Register of Marine Species.
^ Hyatt, A. & Pilsbry, H. A. (1910–1911). Manual of conchology, structural and systematic, with illustrations of the species. Ser. 2, Pulmonata. Vol. 21: Achatinellidae (Amastrinae). Philadelphia: Conchological Department, Academy of Natural Sciences. p. 237. Retrieved 3 December 2024.{{cite book}}: CS1 maint: multiple names: authors list (link) This article incorporates text from this source, which is in the public domain.

Newcomb, W. (1854). "Descriptions of seventy·nine new species of Achatinella, (Swains.) a genus of pulmoniferous mollusks, in the collection of Hugh Cuming, Esq". Proceedings of the Zoological Society of London: 29.
Cowie, R. H., Evenhuis, N. L. & Christensen, C. C. (1995). Catalog of the native land and freshwater molluscs of the Hawaiian Islands. Leiden: Backhuys Publishers. p. 106.{{cite book}}: CS1 maint: multiple names: authors list (link)

External links

Adams, C.B. (1851). "Descriptions of new species of Partula and Achatinella". Contributions to Conchology. 8: 125.

[WoRMS-1] Amastra magna (C. B. Adams, 1851). 24 December 2024. Retrieved through: World Register of Marine Species.

[Hyatt-2] Hyatt, A. & Pilsbry, H. A. (1910–1911). Manual of conchology, structural and systematic, with illustrations of the species. Ser. 2, Pulmonata. Vol. 21: Achatinellidae (Amastrinae). Philadelphia: Conchological Department, Academy of Natural Sciences. p. 237. Retrieved 3 December 2024.{{cite book}}: CS1 maint: multiple names: authors list (link) This article incorporates text from this source, which is in the public domain.

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