Tellimya ferruginosa 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 small marine

Marine (ocean)

Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...

 bivalve

Bivalvia

Bivalvia is a taxonomic class of marine and freshwater molluscs. This class includes clams, oysters, mussels, scallops, and many other families of molluscs that have two hinged shells...

 mollusc

Mollusca

The Mollusca , common name molluscs or mollusksSpelled mollusks in the USA, see reasons given in Rosenberg's ; for the spelling mollusc see the reasons given by , is a large phylum of invertebrate animals. There are around 85,000 recognized extant species of molluscs. Mollusca is the largest...

 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...

 Montacutidae. It is found on the eastern side of the Atlantic Ocean.

Bivalves are molluscs with a body compressed between two usually similar shell valves

Bivalve shell

A bivalve shell is part of the body, the exoskeleton or shell, of a bivalve mollusk. In life, the shell of this class of mollusks is composed of two parts, two valves which are hinged together...

 joined by an elastic ligament. There are teeth at the edge of the shell and the animal has a muscular foot, 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...

s, siphons, mouth and gut and is surrounded by a mantle

Mantle (mollusc)

The mantle is a significant part of the anatomy of molluscs: it is the dorsal body wall which covers the visceral mass and usually protrudes in the form of flaps well beyond the visceral mass itself.In many, but by no means all, species of molluscs, the epidermis of the mantle secretes...

 inside the shell.

Taxonomy

The genus Tellimya used to be included in the family Lasaeidae

Lasaeidae

Lasaeidae is a family of bivalve molluscs, related to the Zebra mussels. They are commonly called kellyclams.-Selected genera and species:* Aligena I...

 but has now been transferred to Montacutidae. Montagu originally described this species as Montacuta ferruginosa but it is currently placed in the genus Tellimya.

Description

This mollusc grows to up to eight millimetres in length and has a fragile, thin glossy shell. It is broadly oval in shape with the umbo or beak and the hinge being in the posterior half. The ligament joining the two valves is internal. The right valve has a single cardinal tooth which is a continuation of a ridge on the shell. The left valve has a single anterior lateral tooth and there are no posterior lateral teeth on either valve. The periostracum

Periostracum

The periostracum is a thin organic coating or "skin" which is the outermost layer of the shell of many shelled animals, including mollusks and brachiopods. Among mollusks it is primarily seen in snails and clams, i.e. in bivalves and gastropods, but it is also found in cephalopods such as the...

 is thin and covered with a thick ferruginous deposit. This obscures the sculpture

Sculpture (mollusc)

The sculpture of a mollusc shell is the three-dimensional ornamentation on the outer surface, as distinct from the basic shape of the shell itself or colouration. Sculpture may be concave as well as convex. Sometimes it has microscopic detail. Sculpture refers to the calcareous outer layer, not the...

 of concentric lines with a small number of faint radial lines. The anterior adductor scar is larger than the posterior one. The line made by the edge of the mantle

Mantle (mollusc)

The mantle is a significant part of the anatomy of molluscs: it is the dorsal body wall which covers the visceral mass and usually protrudes in the form of flaps well beyond the visceral mass itself.In many, but by no means all, species of molluscs, the epidermis of the mantle secretes...

 is wide and the margin is entire. There are a number of tubercles along the ventral portion of the middle fold of the mantle. The interior of the shell is white and sometimes nacreous.

Distribution

Tellimya ferruginosa occurs in the North Sea

North Sea

In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean. In the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively...

, round the British Isles, north to Norway and south to the Mediterranean Sea, Morocco

Morocco

Morocco , officially the Kingdom of Morocco , is a country located in North Africa. It has a population of more than 32 million and an area of 710,850 km², and also primarily administers the disputed region of the Western Sahara...

 and Madeira

Madeira

Madeira is a Portuguese archipelago that lies between and , just under 400 km north of Tenerife, Canary Islands, in the north Atlantic Ocean and an outermost region of the European Union...

.

Biology

Tellimya ferruginosa lives under the surface of the sediment and prefers muddy sand. It is often found living as a commensal

Commensalism

In ecology, commensalism is a class of relationship between two organisms where one organism benefits but the other is neutral...

 of the sea potato, Echinocardium cordatum

Echinocardium cordatum

Echinocardium cordatum, or the sea potato, is a sea urchin in the family Loveniidae. It is found in sub-tidal regions in temperate seas around the world and lives buried in the sandy sea floor.-Description:...

. Up to fourteen of the bivalves have been found associated with one urchin.