''Macrochlamys indica'' or the horntail snail is a species 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 gastropod mollusks that have shells (those without shells are known as ...

, a terrestrial

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 includ ...

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusk, in the family Ariophantidae.

Distribution

This species occurs in countries including: * India,

Lower Bengal Lower may refer to: *Lower (surname) *Lower Township, New Jersey *Lower Receiver (firearms) *Lower Wick Gloucestershire, England See also *Nizhny Nizhny (russian: Ни́жний; masculine), Nizhnyaya (; feminine), or Nizhneye (russian: Ни́� ...

, common at Calcutta. * Egypt This species has not yet become established in the USA, but it is considered to represent a potentially serious threat as a

pest Pest or The Pest may refer to: Science and medicine * Pest (organism), an animal or plant deemed to be detrimental to humans or human concerns ** Weed, a plant considered undesirable * Infectious disease, an illness resulting from an infection ** ...

, an

invasive species An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species ad ...

which could negatively affect agriculture, natural ecosystems, human health or commerce. Therefore, it has been suggested that this species be given top national quarantine significance in the USA.Cowie R. H., Dillon R. T., Robinson D. G. & Smith J. W. (2009). "Alien non-marine snails and slugs of priority quarantine importance in the United States: A preliminary risk assessment". ''American Malacological Bulletin'' 27: 113-132
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. In October 2020 a single horntail was found in Miami-Dade County, Florida.

Shell description

The shell is perforate, depressed, smooth, polished throughout, translucent, pale brownish tawny, not distinctly striated, but with microscopic longitudinal impressed lines, slightly flexuous and not close together. The spire is low, conoid. The suture is slightly impressed. The shell has 5.5 whorls, that are slightly convex above. The last whorl is not descending. The last whorl is rounded at the periphery and moderately convex beneath. The aperture is slightly oblique and broadly lunate. The peristome is thin in one plane, with columellar margin is curved, oblique, never quite vertical, carried forward and briefly reflected above. The width of the shell is 16-18.5 mm. The height of the shell is 8.5 mm.

Anatomy

The animal is purplish grey not black, elongate. The right shell-lobe is small, the left is narrowly reflected over the edge of the peristome, and at the basal side gives off a short tongue-like process. The right dorsal lobe is narrow and elongate, the left in two distinct portions. In the genitalia is a moderately long cylindrical blunt kalc-sac is given off at the junction of the vas deferens, and the caecum of the penis, to which the retractor muscle is attached, is sharply coiled. The dart-sac is long, the spermatheca short and elongately pearshaped. The

radula The radula (, ; plural radulae or radulas) is an anatomical structure used by molluscs for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food ...

contains about 88 rows of teeth, with the arrangement: 34.2.9.1.9.2.34 (45.1.45).

References

The article incorporates public domain text from the reference. Blanford W. T. & Godwin-Austen H. H. 1908. '' The Fauna of British India, Including Ceylon and Burma''
Mollusca. Testacellidae and Zonitidae
'. Taylor & Francis, London
page 95
96.

Distribution

Shell description

Anatomy

References

Further reading