''Helicina guppyi'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

tropical The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in the Southern Hemisphere at S. The tropics are also referred to ...

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 ...

with an operculum, a terrestrial

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 Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

in the family Helicinidae.

Shell description

The species is smaller and lower- spired than the other Dominican ''Helicina'' species, and always has a dull brown colour, a paler

aperture In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and focal length of an optical system determine the cone angle of a bundle of rays that come to a focus in the image plane. An opt ...

and a hairy

periostracum The periostracum ( ) is a thin, organic coating (or "skin") that is the outermost layer of the shell of many shelled animals, including molluscs and brachiopods. Among molluscs, it is primarily seen in snails and clams, i.e. in gastropods and ...

; ‘covered with a velvety epidermis’, weakly keeled, with a columellar denticle. Its size is 5-8.5 mm.

Distribution

This species lives in

Guadeloupe Guadeloupe (; ; gcf, label=Antillean Creole, Gwadloup, ) is an archipelago and overseas department and region of France in the Caribbean. It consists of six inhabited islands—Basse-Terre, Grande-Terre, Marie-Galante, La Désirade, and the ...

Dominica Dominica ( or ; Kalinago: ; french: Dominique; Dominican Creole French: ), officially the Commonwealth of Dominica, is an island country in the Caribbean. The capital, Roseau, is located on the western side of the island. It is geographically ...

and in

Martinique Martinique ( , ; gcf, label=Martinican Creole, Matinik or ; Kalinago: or ) is an island and an overseas department/region and single territorial collectivity of France. An integral part of the French Republic, Martinique is located in th ...

. This is the most common of the helicinids in Dominica, but generally restricted to the

leeward Windward () and leeward () are terms used to describe the direction of the wind. Windward is ''upwind'' from the point of reference, i.e. towards the direction from which the wind is coming; leeward is ''downwind'' from the point of reference ...

side of the island.

Taxonomy

Robert John Lechmere Guppy (1868) Guppy R. J. L. (1868). "On the terrestrial mollusks of Dominica and Grenada, with an account of some new species from Trinidad". '' Annals and Magazine of Natural History'' (4)1
429
442. described two taxa from Dominica based on shell variation within this species; both names were

preoccupied The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently. * In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linn ...

William Harper Pease William Harper Pease (1824–1871) was a 19th-century American conchologist, shell collector and malacologist. He described many species of Indo-Pacific marine mollusks from the Cuming collection. He moved in 1849 to Honolulu Honolulu ( ...

(1871) provided a substitute name in his treatment of Indo-Pacific species. This species was placed in the subgenus '' Striatemoda'' by Horace Burrington Baker (1940) Baker H. B. (1940). "'' Striatemoda'', new subgenus of ''

Alcadia ''Alcadia'' is a genus of tropical and subtropical land snails with an operculum, terrestrial gastropod mollusks in the family Helicinidae. Species Species within the genus ''Alcadia'' include: * ''Alcadia affinis'' C.B. Adams, 1846 * '' A ...

'' (?), type of ''A.'' (''Emoda''?) ''striata'' (Lamarck), from Puerto Rico". ''Nautilus'' 54
71
based on Guppy’s (1868) comparison with the Puerto Rican '' Alcadia subfusca'' (Menke, 1828), and also on

Pilsbry Henry Augustus Pilsbry (7 December 1862 – 26 October 1957) was an American biologist, malacologist and carcinologist, among other areas of study. He was a dominant presence in many fields of invertebrate taxonomy for the better part of a centu ...

’s (1892) Pilsbry H. A. (1892). "On a collection of land Mollusca from the Island of Dominica, West Indies". ''Transactions of the Connecticut Academy of Science'' 8
356
358. erroneous placement of this species with the Hispaniolan '' Alcadia rufa'' (L. Pfeiffer, 1857). There is expected the forthcoming revision of the Lesser Antillean Helicinidae by Ira Richling (from

Kiel Kiel () is the capital and most populous city in the northern Germany, German state of Schleswig-Holstein, with a population of 246,243 (2021). Kiel lies approximately north of Hamburg. Due to its geographic location in the southeast of the J ...

, Germany).

Ecology

This species is usually collected on the trunks of trees, where it is well camouflaged on tree bark, or among

detritus In biology, detritus () is dead particulate organic material, as distinguished from dissolved organic material. Detritus typically includes the bodies or fragments of bodies of dead organisms, and fecal material. Detritus typically hosts commun ...

and leaves on the ground.

References

This article incorporates CC-BY-3.0 text from the reference.Robinson D. G., Hovestadt A., Fields A. & Breure A. S. H. (July 2009). "The land Mollusca of Dominica (Lesser Antilles), with notes on some enigmatic or rare species". ''Zoologische Mededelingen'' 83 http://www.zoologischemededelingen.nl/83/nr03/a13 {{DEFAULTSORT:Helicina Guppyi Helicinidae Gastropods described in 1871