Amastra paulula

Amastra paulula
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Order:	Stylommatophora
Family:	Amastridae
Genus:	Amastra
Species:	A. paulula
Binomial name
	Amastra paulula; C. M. Cooke, 1917
Synonyms
	Amastra (Metamastra) paulula C. M. Cooke, 1917 alternative representation

Amastra paulula 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 9.8 mm, its diameter 5.4 mm.

(Original description) The shell is perforate, dextral, and ovate, appearing very light brown in its fossilized state. It is relatively thin, with the spire outlined in a convex manner and culminating in an obtuse summit.

The whorls of the protoconch increase rapidly in size. They are convex, and appear smooth, showing no discernible sculpture even under magnification. The subsequent whorls are convex and separated by a very shallow suture, with almost regular fine, thin growth wrinkles adorning their surface. The body whorl is large and rotund.

The aperture is oblique and broad, with a highly convex outer margin accented by a delicate lip rib. The columella is narrowly triangular and slightly oblique, featuring a concave inner margin and an erect, straight outer margin. The columellar fold is strong, nearly transverse, and terminates abruptly near the base of the columella and close to the outer margin.

The umbilicus is distinctly open and cleft-like, adding to the shell's delicate structure.^[2]

Distribution

This species is endemic to Hawai, occurring on Oahu Island.

References

^ Amastra paulula C. M. Cooke, 1917. 31 December 2024. Retrieved through: World Register of Marine Species.
^ Cooke, C.M. (1917). "Some new species of Amastra". Occasional Papers of the Bernice P. Bishop Museum. 3 (3): 22. Retrieved 31 December 2024. 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. pp. 1–248.{{cite book}}: CS1 maint: multiple names: authors list (link)

[WoRMS-1] Amastra paulula C. M. Cooke, 1917. 31 December 2024. Retrieved through: World Register of Marine Species.

[2] Cooke, C.M. (1917). "Some new species of Amastra". Occasional Papers of the Bernice P. Bishop Museum. 3 (3): 22. Retrieved 31 December 2024. This article incorporates text from this source, which is in the public domain.

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