''Solemya elarraichensis'' 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 ...

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

bivalve Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, biv ...

mollusc in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Solemyidae Solemyidae is a family of saltwater clams, marine protobranch bivalve mollusks in the order Solemyida. Biology Solemyids are remarkable in that their digestive tract is either extremely small or non-existent, and their feeding appendages are to ...

. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found els ...

to the deep-water

mud volcano A mud volcano or mud dome is a landform created by the eruption of mud or slurries, water and gases. Several geological processes may cause the formation of mud volcanoes. Mud volcanoes are not true igneous volcanoes as they do not produce l ...

slopes in the

Gulf of Cadiz A gulf is a large inlet from the ocean into the landmass, typically with a narrower opening than a bay, but that is not observable in all geographic areas so named. The term gulf was traditionally used for large highly-indented navigable bodies ...

in the eastern Atlantic Ocean.

Description

''Solemya elarraichensis'' reaches a maximum length of about . The fragile

valves A valve is a device or natural object that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways. Valves are technically fitting ...

are equal in size and subcylindrical, with the beaks nearer the posterior end. The beaks are indistinct and the umbos sunken, and there are no hinge teeth. The ligament connecting the valves is primarily internal. The exterior of the shell is sculpted by fine radial ridges, about five at the posterior end and eleven at the anterior end. The shell has a persistent thin

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 a ...

which extends beyond the valve margins. It is yellowish-brown at first but darkens with age.

Distribution and habitat

''Solemya elarraichensis'' is

to the volcanic area in the Gulf of Cadiz, off the coast of Spain. The whole area is under compressive deformation and mud volcanism and the processes associated with the escape of

hydrocarbon In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or ...

-rich fluids sustain a broad diversity of chemosynthetic organisms. The area includes over forty

es, a type of

cold seep A cold seep (sometimes called a cold vent) is an area of the ocean floor where hydrogen sulfide, methane and other hydrocarbon-rich fluid seepage occurs, often in the form of a brine pool. ''Cold'' does not mean that the temperature of the see ...

, at depths between , and active

methane Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The relative abundance of methane on Ear ...

seepage occurs in several places.

References

{{Taxonbar, from=Q14363656 Solemyidae Molluscs described in 2011