''Amastra badia'' is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of air-breathing

land snail A land snail is any of the numerous species of snail that live on land, as opposed to the sea snails and freshwater snails. ''Land snail'' is the common name for terrestrial molluscs, terrestrial gastropod mollusks that have gastropod shell, shel ...

, a

terrestrial Terrestrial refers to things related to land or the planet Earth, as opposed to extraterrestrial. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on o ...

pulmonate Pulmonata or pulmonates is an informal group (previously an order, and before that, a subclass) of snails and slugs characterized by the ability to breathe air, by virtue of having a pallial lung instead of a gill, or gills. The group inclu ...

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

mollusc Mollusca is a phylum of protostome, protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant taxon, extant species of molluscs are recognized, making it the second-largest animal phylum ...

in the family

Amastridae Amastridae is a Taxonomy (biology), taxonomic family (biology), family of small, air-breathing, land snails, Terrestrial animal, terrestrial pulmonate gastropod mollusks in the superfamily Pupilloidea.MolluscaBase eds. (2021). MolluscaBase. Amast ...

Description

The length of the shell attains 17 mm, its diameter 12 mm. (Original description) The shell contains 6½

whorl A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). In nature File:Photograph and axial plane floral diagra ...

s. The shell is dextral, imperforate, relatively thin, and elongately ovate-conic. Its surface is glossy, adorned with delicate, closely spaced thread-like rib-striae aligned with the growth lines. The whorls of the

protoconch A protoconch (meaning first or earliest or original shell) is an embryonic or larval shell which occurs in some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod. In older texts it is also called " ...

are distinctly radiately sulcated. The shell's coloration is a rich dark chestnut-brown, decorated with light brown zigzag or undulating lines and markings. It consists of 6½ slightly convex whorls, with a moderately impressed suture. The

aperture In optics, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image o ...

is oval and slightly oblique, with a livid white interior that subtly reveals the brown exterior coloration. The peristome is acute and minimally thickened on the inner side. The

columella Lucius Junius Moderatus Columella (, Arabic: ) was a prominent Roman writer on agriculture in the Roman Empire. His in twelve volumes has been completely preserved and forms an important source on Roman agriculture and ancient Roman cuisin ...

is white, flexuous, and ends abruptly in a thin, slightly arched lamellar plait. (Later supplemental description by Hyatt, A. & Pilsbry, H. A. ) In color, pattern and sculpture of the later whorls this form resembles '' Amastra undata'' (Baldwin, 1895). Whether there are spiral decussating lines on the

body whorl The body whorl is part of the morphology (biology), morphology of the gastropod shell, shell in those gastropod mollusks that possess a coiled shell. The term is also sometimes used in a similar way to describe the shell of a cephalopod mollusk ...

of the type specimen was not stated by Baldwin, but they are present in one specimen examined from

Moanalua Moanalua is a valley, a stream, an ahupuaa, and a residential neighborhood in Honolulu, Hawaii. The valley extends inland from behind Āliapaakai crater (Salt Lake) to the crest of the Koʻolau Range. Neighboring areas include Māpunapuna an ...

, wanting in another. In those from Waimano the spirals are either very faint, hardly noticeable, or wanting. ''A. badia'' differs from ''A. undata'' by its embryonic sculpture and the less obese, more ovate shape. The columellar lamella penetrates two whorls. The axis is imperforate in the adult and later neanic stages, but in the half -grown shell there is a rather widely open umbilicus, width about 1 mm. The embryonic whorls are much more strongly sculptured than in ''A. undata''. After the smooth initial half -whorl, coarse vertical ribs appear, changing to an irregular coarse malleation on the last half of the second whorl. Then short, rather coarse protractive ribs appear below the suture, while above the lower suture there is another system of smaller, retractive folds, the two systems interfering about the middle of the whorl. The third whorl has fine growth-lines only, and the color-pattern appears as a few white spots and irregular stripes. The ground-color of adults is dark red, upon which there are yellow streaks or spots. In some shells from Aeia the body whorl has a yellow suffusion, faintly mottled with dark. The shell is quite thin.

Distribution

This species is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

, occurring on

Oahu Oahu (, , sometimes written Oahu) is the third-largest and most populated island of the Hawaiian Islands and of the U.S. state of Hawaii. The state capital, Honolulu, is on Oahu's southeast coast. The island of Oahu and the uninhabited Northwe ...

Island.

References

External links

* {{Taxonbar, from=Q131402556 badia Gastropods described in 1895