''Helicodiscus parallelus'',

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contra ...

the compound coil, is a

species In biology, a species is the basic unit of Taxonomy (biology), 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 ...

of small air-breathing land snail, a

terrestrial Terrestrial refers to things related to land or the planet Earth. 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 or near the ground, as opposed to ...

pulmonate gastropod

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 es ...

in the family

Helicodiscidae Helicodiscidae is a family of small air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Punctoidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005). Genera Genera within the family ...

. ''Helicodiscus parallelus'' is the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen( ...

of the genus ''Helicodiscus''. Helicodiscus parallelus shell

Distribution

This species occurs in the following countries and islands: * Northern

Mexico Mexico ( Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guate ...

. *

Great Lakes The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes in the mid-east region of North America that connect to the Atlantic Ocean via the Saint Lawrence River. There are five la ...

region.

List of non-marine mollusks of the Indiana Dunes This is a list of the non-marine mollusks of the Indiana Dunes. Indiana Dunes National Park is a National Park Service unit on the shore of Lake Michigan in the state of Indiana, United States. A BioBlitz took place there on May 15 and 16, 2009. ...

, Lake Erie, Indiana. *

Great Britain Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the largest European island and the ninth-largest island in the world. It is ...

as a "hot-house alien"

References

Helicodiscidae Fauna of the Great Lakes region (North America) Molluscs of Mexico Molluscs of the United States Gastropods described in 1821 {{Helicodiscidae-stub