The Mytilidae are a

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

of small to large marine and brackish-water

bivalve Bivalvia () or bivalves, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class (biology), class of aquatic animal, aquatic molluscs (marine and freshwater) that have laterally compressed soft bodies enclosed b ...

mollusc Mollusca is a phylum of protostome, protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant taxon, extant species of molluscs are recognized, making it the second-largest animal phylum ...

s in the

order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

Mytilida Mytilida is an order of marine bivalve molluscs, commonly known as true mussels. There is one extant superfamily, the Mytiloidea, with a single extant family, the Mytilidae. Species in the order Mytilida are found worldwide, but they are more ...

. One of the genera, ''

Limnoperna ''Limnoperna'' is a genus of bivalves belonging to the family Modiolidae . The species of this genus are found in Southern America, Southeastern Asia and Australia. Species: *''Limnoperna atrata'' : synonym of ''Vignadula atrata'' (Lischke, 1 ...

'', even inhabits

freshwater Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include non-salty mi ...

environments. Mytilidae, which contains some 52 genera, is the only extant family within the order Mytilida. Species in the family Mytilidae are found worldwide, but they are more abundant in colder seas, where they often form uninterrupted beds on rocky shores in the

intertidal zone The intertidal zone or foreshore is the area above water level at low tide and underwater at high tide; in other words, it is the part of the littoral zone within the tidal range. This area can include several types of habitats with various ...

and the shallow subtidal. The subfamily Bathymodiolinae is found in

deep-sea The deep sea is broadly defined as the ocean depth where light begins to fade, at an approximate depth of or the point of transition from continental shelves to continental slopes. Conditions within the deep sea are a combination of low tempe ...

habitats. Mytilids include the well-known, edible sea mussels. A common feature of the shells of mussels is an asymmetrical shell, which has a thick, adherent

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 an ...

. The animals attach themselves to a solid substrate using a

byssus A byssus () is a bundle of filaments secreted by many species of bivalve mollusc that function to attach the mollusc to a solid surface. Species from several families of clams have a byssus, including pen shells ( Pinnidae), true mussels (Mytili ...

. A 2020 study of the phylogeny of the Mytilidae recovered two main

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

s derived from an

epifaunal Fauna (: faunae or faunas) is all of the animal life present in a particular region or time. The corresponding terms for plants and fungi are ''flora'' and ''funga'', respectively. Flora, fauna, funga and other forms of life are collectively r ...

ancestor, with subsequent lineages shifting to other lifestyles, and correlating

convergent evolution Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last comm ...

siphon A siphon (; also spelled syphon) is any of a wide variety of devices that involve the flow of liquids through tubes. In a narrower sense, the word refers particularly to a tube in an inverted "U" shape, which causes a liquid to flow upward, abo ...

traits.

Subfamilies and genera

, the

World Register of Marine Species The World Register of Marine Species (WoRMS) is a taxonomic database that aims to provide an authoritative and comprehensive catalogue and list of names of marine organisms. Content The content of the registry is edited and maintained by scien ...

accepts 32 genera split into eight subfamilies.

Subfamily Brachidontinae

*''

Brachidontes ''Brachidontes'' is a genus of mussels in the family Mytilidae The Mytilidae are a family (biology), family of small to large Marine life, marine and Brackish water, brackish-water bivalve molluscs in the order (biology), order Mytilida. One o ...

'' Swainson, 1840 *''

Geukensia ''Geukensia'' is a genus of marine bivalve mollusc in the Mytilidae family, naturally found in the western Atlantic. Species Species within the genus ''Geukensia'' include:Ischadium ''Ischadium'' is a monotypic genus of mussels in the family Mytilidae. The sole species is ''Ischadium recurvum'', known as the "Hooked mussel" or "Bent mussel". It can be found along the Atlantic coast of North America, ranging from Cape Cod to ...

'' Jukes-Browne, 1905 *''

Mytilaster ''Mytilaster'' is a genus of marine mussels from the warmer waters of the Atlantic Ocean and Mediterranean Basin. The type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'' ...

'' Monterosato, 1883

Subfamily Crenellinae

*†'' Arcoperna'' Conrad, 1865 *''

Arcuatula ''Arcuatula'' is a genus of mussels from the family Mytilidae The Mytilidae are a family (biology), family of small to large Marine life, marine and Brackish water, brackish-water bivalve molluscs in the order (biology), order Mytilida. One of ...

'' Jousseaume, 1919 *'' Arvella'' Scarlato, 1960 *''

Choromytilus ''Choromytilus'' is a genus of mussel, a marine bivalve mollusc in the family Mytilidae The Mytilidae are a family (biology), family of small to large Marine life, marine and Brackish water, brackish-water bivalve molluscs in the order (biol ...

'' T. Soot-Ryen, 1952 *'' Crenella'' T. Brown, 1827 *'' Exosiperna'' Iredale, 1929 *'' Musculus'' Röding, 1798 *''

Mytella ''Mytella'' is a genus of saltwater clams, marine (ocean), marine bivalve molluscs in the subfamily Arcuatulinae of the family Mytilidae, the mussels. Species * ''Mytella brasiliensis'' (Gray, 1825) * ''Mytella guyanensis'' J.B.P.A. Lamarck, 18 ...

'' T. Soot-Ryen, 1955 *'' Parabrachidontes'' K. S. Tan, S. H. M. Tan, Sanpanich, Duangdee & Ambarwati, 2024 *'' Perna'' Philipsson, 1788 *'' Rhomboidella'' Monterosato, 1884 *†'' Semimodiola'' Cossmann, 1887 *''

Solamen ''Solamen'' is a genus of saltwater, brackish water and freshwater clams, marine (ocean), marine bivalve molluscs in the subfamily Crenellinae of the family Mytilidae, the mussels.MolluscaBase eds. (2022). MolluscaBase. Solamen Iredale, 1924. Acc ...

'' Iredale, 1924 *'' Vilasina'' Scarlato, 1960

Subfamily Dacrydiinae

*''

Dacrydium ''Dacrydium'' is a genus of conifers belonging to the podocarp family Podocarpaceae. Sixteen species of evergreen Plant sexuality, dioecious trees and shrubs are presently recognized. The genus was first described by Solander in 1786, and former ...

'' Torell, 1859

Subfamily Lithophaginae

*''

Lithophaga ''Lithophaga'', the date mussels, are a genus of medium-sized marine bivalve molluscs in the family Mytilidae. Some of the earliest fossil ''Lithophaga'' shells have been found in Mesozoic rocks from the Alps and from Vancouver Island.Ludvigsen, ...

'' Röding, 1798

Subfamily Mytilinae

*''

Adula Adula may refer to *The Adula Alps * Rheinwaldhorn, a mountain called in Italian "l'Adula" * Adula Formation, a geological formation in China {{disambig ...

'' H. Adams & A. Adams, 1857 *'' Crenomytilus'' T. Soot-Ryen, 1955 *'' Dentimodiolus'' Iredale, 1939 *'' Gregariella'' Monterosato, 1883 *'' Mytilus'' Linnaeus, 1758 *†'' Praemytilus'' F. W. Anderson & L. R. Cox, 1948 *'' Trichomya'' Ihering, 1900

Subfamily Mytiliseptinae

*'' Austromytilus'' Laseron, 1956 *'' Mytilisepta'' T. Habe, 1951 *'' Perumytilus'' Olsson, 1961 *'' Semimytilus'' T. Soot-Ryen, 1955

Subfamily Septiferinae

*'' Septifer'' Récluz, 1848

†Subfamily Xenomytilinae

*†'' Lycettia'' L. R. Cox, 1937 *†'' Xenomytilus'' Squires & Saul, 2006

''
Incertae sedis or is a term used for a taxonomy (biology), taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty ...
''

*†'' Admytilus'' Berezovsky, 2015 *'' Amygdalum'' Megerle von Mühlfeld, 1811 *†'' Arcomytilus'' Agassiz, 1842 *†'' Assytilus'' Berezovsky, 2015 *'' Aulacomya'' Mörch, 1853 *†'' Cuneolus'' Stephenson, 1941 *†'' Inoperna'' Conrad, 1873 *†'' Limnolycettia'' C. M. Kolesnikov, 1980 *†'' Mauricia'' G. D. Harris, 1919 *†'' Mysidioptera'' Salomon, 1895 *†'' Mytilosootus'' Stilwell & Zinsmeister, 1992 *†'' Paramusculus'' Kadolsky, 1989 *†'' Promytilus'' Newell, 1942 *†'' Regulifer'' Fürsich & Werner, 1988 *†'' Rhynchomytilus'' Rollier, 1914 *†'' Samiolus'' Kiel & Taviani, 2017 *'' Urumella'' Hayami & Kase, 1993 *†'' Volsellina'' Newell, 1942

References

External links

* * {{Authority control Bivalve families Taxa named by Constantine Samuel Rafinesque