| Amphicyclotulus amethystinus | |
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Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Gastropoda |
| Subclass: | Caenogastropoda |
| Order: | Architaenioglossa |
| Superfamily: | Cyclophoroidea |
| Family: | Neocyclotidae |
| Genus: | Amphicyclotulus |
| Species: | A. amethystinus |
| Binomial name | |
| Amphicyclotulus amethystinus | |
| Synonyms [2] | |
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Amphicyclotulus amethystinus is a species of tropical land snail with a gill and an operculum, a terrestrial gastropod mollusc in the family Neocyclotidae. [3]
The shell is smooth, shining, not striate spirally, generally somewhat more depressed, deep chestnut or reddish brown. Whorls are a little flattened near the suture. [1] The species may have subtle spiral striation, although there exists considerable variation; axial growth lines are clearly visible. [2]
The operculum is horny, diaphanous, concave externally, cartilaginous within, the nucleus projecting internally; with from ten to fourteen very narrow whorls, their rather lamellar outer edges slightly free. [1]
Amphicyclotulus amethystinus has spiral threads absent or only weakly present. [2] There are found only two species in the genus Amphicyclotulus in Dominica. The other species is Amphicyclotulus dominicensis and it has spiral cords clearly present and raised. [2]
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Robert John Lechmere Guppy (1868) [1] noted that this species is not found above 1000 m. Although he recognized two "forms", he did not recognize two separate species. George French Angas (1884) [4] subsequently recorded "Cyclophorus amethystinus" from altitudes above 1200 m. Paul Bartsch (1942) [5] restricted the name amesthystinus to Guppy’s var. β, the "smooth, shining, not striate spirally" form. [2]
This species is endemic to in Dominica. [2]
The type locality is Laudat, Dominica. [2] The holotype is in National Museum of Natural History under number 535856. [2]
All known localities of Amphicyclotulus amethystinus include: [2]
This article incorporates CC-BY-3.0 text from the reference [2] and public domain text from the reference. [1]