Amastra perversa

Amastra perversa
	Shell of Amastra perversa (holotype)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Order:	Stylommatophora
Family:	Amastridae
Genus:	Amastra
Species:	A. perversa
Binomial name
	Amastra perversa; Hyatt & Pilsbry, 1911
Synonyms
	Amastra (Heteramastra) perversa Hyatt & Pilsbry, 1911 alternative representation

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

Description

The length of the shell attains 11.5 mm, its diameter 5.5 mm.

(Original description) The shell contains 6½ whorls. The shell is sinistral, oblong-turrite, and relatively solid. The spire tapers slightly near the summit, giving it a subtle contracted appearance.

The whorls of the protoconch are delicately ribbed, resembling those of Astrama laeva, while the subsequent whorls display faint and subdued growth wrinkles, which are less pronounced than in A. laeva.

The aperture is small and somewhat thickened on the interior, providing structural reinforcement. The columellar lamella is small, oblique, and receding, contributing to the shell's refined and understated design.^[2]

Distribution

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

References

^ Amastra perversa Hyatt & Pilsbry, 1911. 3 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. 280. 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.

Cowie, R. H., Evenhuis, N. L. & Christensen, C. C. (1995). Catalog of the native land and freshwater molluscs of the Hawaiian Islands. vi. Leiden: Backhuys Publishers. p. 107.{{cite book}}: CS1 maint: multiple names: authors list (link)

[WoRMS-1] Amastra perversa Hyatt & Pilsbry, 1911. 3 December 2024. Retrieved through: World Register of Marine Species.

[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. 280. 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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