Melanopsis is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of freshwater snail

Freshwater snail

A freshwater snail is one kind of freshwater mollusc, the other kind being freshwater clams and mussels, i.e. freshwater bivalves. Specifically a freshwater snail is a gastropod that lives in a watery non-marine habitat. The majority of freshwater gastropods have a shell, with very few exceptions....

s with a gill

Gill

A gill is a respiratory organ found in many aquatic organisms that extracts dissolved oxygen from water, afterward excreting carbon dioxide. The gills of some species such as hermit crabs have adapted to allow respiration on land provided they are kept moist...

 and an operculum

Operculum (gastropod)

The operculum, meaning little lid, is a corneous or calcareous anatomical structure which exists in many groups of sea snails and freshwater snails, and also in a few groups of land snails...

, aquatic

Aquatic animal

An aquatic animal is an animal, either vertebrate or invertebrate, which lives in water for most or all of its life. It may breathe air or extract its oxygen from that dissolved in water through specialised organs called gills, or directly through its skin. Natural environments and the animals that...

 gastropod mollusks in the family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Melanopsidae

Melanopsidae

Melanopsidae, common name melanopsids, is a family of freshwater gastropods in the clade Sorbeoconcha. Species in this family are native to southern and eastern Europe, northern Africa, parts of the Middle East, New Zealand, and freshwater streams of some large South Pacific islands.These snails...

. The genus first appeared in the Cretaceous

Cretaceous

The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

.

Melanopsis is the type genus

Type genus

In biological classification, a type genus is a representative genus, as with regard to a biological family. The term and concept is used much more often and much more formally in zoology than it is in botany, and the definition is dependent on the nomenclatural Code that applies:* In zoological...

 of the family Melanopsidae.

Distribution

These snails are found in southern Europe

Europe

Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

, North Africa

North Africa

North Africa or Northern Africa is the northernmost region of the African continent, linked by the Sahara to Sub-Saharan Africa. Geopolitically, the United Nations definition of Northern Africa includes eight countries or territories; Algeria, Egypt, Libya, Morocco, South Sudan, Sudan, Tunisia, and...

, Asia Minor

Asia Minor

Asia Minor is a geographical location at the westernmost protrusion of Asia, also called Anatolia, and corresponds to the western two thirds of the Asian part of Turkey...

, New Caledonia

New Caledonia

New Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...

 and New Zealand

New Zealand

New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

.

Description

Their shells

Mollusc shell

The mollusc shell is typically a calcareous exoskeleton which encloses, supports and protects the soft parts of an animal in the phylum Mollusca, which includes snails, clams, tusk shells, and several other classes...

 are ovate, with a short spire

Spire (mollusc)

A spire is a descriptive term for part of the coiled shell of mollusks. The word is a convenient aid in describing shells, but it does not refer to a very precise part of shell anatomy: the spire consists of all of the whorls except for the body whorl...

, and a large elongated body whorl

Body whorl

Body whorl is part of the morphology of a coiled gastropod mollusk.- In gastropods :In gastropods, the body whorl, or last whorl, is the most recently-formed and largest whorl of a spiral or helical shell, terminating in the aperture...

. The outer lip of the aperture

Aperture (mollusc)

The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where part of the body of the animal emerges for locomotion, feeding, etc....

 is thin, but the inner lip has a smooth parietal callus

Parietal callus

A parietal callus is a feature of the shell anatomy of some groups of snails, i.e. gastropods. It is a thickened calcareous deposit which may be present on the parietal wall of the aperture of the adult shell. The parietal wall is the margin of the aperture and part of the wall of the body whorl...

, thickened into a pad over the parietal wall.

Species

Species within the genus Melanopsis include:

• Melanopsis aetolica †
• Melanopsis ajkaensis †
• Melanopsis ammonis
• Melanopsis anceps †
• Melanopsis ancillaroides †
• Melanopsis antediluviana †
• Melanopsis arbalensis Pérès, 1939
• Melanopsis avellana †
• Melanopsis bonelli †
• Melanopsis brevicula Pallary, 1918
• Melanopsis brevis
• Melanopsis buccinoidea (Olivier, 1801)
• Melanopsis buccinulum †
• Melanopsis cariosa (Linnaeus, 1767)
• Melanopsis cerithiopsis
• Melanopsis chlorotica Pallary, 1921
• Melanopsis coaequata †
• Melanopsis costata (Olivier, 1804)
• Melanopsis cylindrica †
• Melanopsis delessi †
• Melanopsis dufouri
• Melanopsis eleis †
• Melanopsis entzi †
• Melanopsis etrusca
  Melanopsis etrusca
  Melanopsis etrusca is a species of freshwater snail with a gill and an operculum, an aquatic gastropod mollusk in the family Melanopsidae. Its natural habitat is rivers. It is threatened by habitat loss.- Distribution :This species is endemic to Italy....
  
  Brot, 1862
• Melanopsis ferussaci
• Melanopsis fossilis (Gmelin) - † late Neogene
• Melanopsis frustulum
• Melanopsis fuchsi †
• Melanopsis gorceixi †
• Melanopsis handmanniana †
• Melanopsis hennersdorfensis †
• Melanopsis impressa †
• Melanopsis kleini †
• Melanopsis laubrierei †
• Melanopsis letourneuxi Bourguignat, 1880
• Melanopsis lorcana
• Melanopsis macrosculpturata †
• Melanopsis magnifica Bourguignat, 1884
• Melanopsis mourebeyensis Pallary, 1921
• Melanopsis multiformis †
• Melanopsis narzolina †
• Melanopsis obediensis †
• Melanopsis ovularis †
• Melanopsis oxycantha †
• Melanopsis parreyssii (Philippi, 1847) - synonym: Melanopsis hungarica Kormos, 1904
• Melanopsis pechinatii
• Melanopsis petrovici †
• Melanopsis praemorsa (Linnaeus, 1758) - type species
• Melanopsis propheatarum
• Melanopsis pseudoimpressa †
• Melanopsis pygmaea †
• Melanopsis saharica Bourguignat, 1864
• Melanopsis saulcyi
• Melanopsis scalaris Gassies, 1856
• † Melanopsis serchensis Vidal, 1874 - from Maastrichtian
  Maastrichtian
  The Maastrichtian is, in the ICS' geologic timescale, the latest age or upper stage of the Late Cretaceous epoch or Upper Cretaceous series, the Cretaceous period or system, and of the Mesozoic era or erathem. It spanned from 70.6 ± 0.6 Ma to 65.5 ± 0.3 Ma...
  
  
• Melanopsis sodalis †
• Melanopsis subgraëllsiana Bourguignat, 1864
• Melanopsis sturi †
• Melanopsis tihanyensis †
• Melanopsis tricarinata
• Melanopsis trifasciata
  Melanopsis trifasciata
  Melanopsis trifasciata is a species of freshwater snail with a gill and an operculum, an aquatic gastropod mollusk in the family Melanopsidae.This species of snail is found only in streams and brackish estuaries in New Zealand.-References:...
  
  Gray, 1843
• Melanopsis turgida Pallary, 1927
• Melanopsis turriformis †
• Melanopsis vindobonensis †
• Melanopsis wagneri

(Extinct taxa indicated by a dagger

Dagger (typography)

A dagger, or obelisk. is a typographical symbol or glyph. The term "obelisk" derives from Greek , which means "little obelus"; from meaning "roasting spit"...

, †.)