Amastra nubigena

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Amastra nubigena is a small land snail that breathes air and lives on Maui in Hawaii. It belongs to the family Amastridae.

Shell details:
- Size: about 10.2 mm long and 5.5 mm wide.
- Shape and color: imperforate, left-coiling (sinistral), oval-turrite, dark chocolate with a pale patch around the columella.
- Surface: matte, except near the opening where the outer layer has worn away.
- Whorls: about 6¼ in total. The spire is slightly concave near the apex and acute at the tip.
- Sculpture: the first half-whorl is smooth; the next whorl has arcuate riblets and a ridge above the suture; later whorls show finer rib-striations. Early whorls are keeled, with the carina sometimes visible above the suture; the penultimate whorl shows this less distinctly. The body whorl is a bit swollen.
- Aperture: the outer lip has a white internal thickening; the columellar lamella is moderately strong and oblique.

Taxonomy:
- Kingdom: Animalia; Phylum: Mollusca; Class: Gastropoda; Order: Stylommatophora; Family: Amastridae; Genus: Amastra; Species: nubigena.
- Binomial name: Amastra nubigena (Pilsbry & C. M. Cooke, 1914).
- Synonyms: Amastra (Heteramastra) nubigena.