Viviparus quadratus, is a species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 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....

 with 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...

 and 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...

, an 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 mollusk 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...

 Viviparidae, the river snails.

Subspecies

Subspecies within this species include:

• Viviparus quadratus disparis
• Viviparus quadratus grahami Chen, 1945

Distribution

Recent distribution of Viviparus quadratus include Northeast Thailand and China.

This species is also known from Upper Pleistocene of China.

Human use

Viviparus quadratus is common animal food used in aquaculture

Aquaculture

Aquaculture, also known as aquafarming, is the farming of aquatic organisms such as fish, crustaceans, molluscs and aquatic plants. Aquaculture involves cultivating freshwater and saltwater populations under controlled conditions, and can be contrasted with commercial fishing, which is the...

 to feed fish black carp

Black carp

The black carp is a species of cyprinid fish indigenous to China, and widely cultivated for food and Chinese medicine. It is the sole species of the genus Mylopharyngodon. The black carp grows to a length of up to three feet , and over 70 pounds , generally feeding on snails and mussels...

 in China.

This species is also eaten by humans. In Northeast Thailand Viviparus quadratus disparis they are collected by hand or with a handnet from canals, swamps, ponds and flooded rice paddy fields during the rainy season. During the dry season, snails live under dried mud. Collectors use a spade

Spade

A spade is a tool designed primarily for the purpose of digging or removing earth. Early spades were made of riven wood. After the art of metalworking was discovered, spades were made with sharper tips of metal. Before the advent of metal spades manual labor was less efficient at moving earth,...

 to scrape the ground to find and catch them. Generally they are collected by both men and women. The snails are then cleaned and cooked in a curry

Curry

Curry is a generic description used throughout Western culture to describe a variety of dishes from Indian, Pakistani, Bangladeshi, Sri Lankan, Thai or other Southeast Asian cuisines...

. They are also parboiled in salted water and eat together with green papaya

Papaya

The papaya , papaw, or pawpaw is the fruit of the plant Carica papaya, the sole species in the genus Carica of the plant family Caricaceae...

salad.