The Alosidae, or the shads, 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 clupeiform fishes. The family currently comprises four genera worldwide, and about 32 species. The shads are

pelagic The pelagic zone consists of the water column of the open ocean and can be further divided into regions by depth. The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or water column between the sur ...

(open water) schooling fish, of which many are

anadromous Fish migration is mass relocation by fish from one area or body of water to another. Many types of fish migrate on a regular basis, on time scales ranging from daily to annually or longer, and over distances ranging from a few metres to thousa ...

or even landlocked. Several species are of commercial importance, e.g. in the genus '' Alosa'' (river herrings), ''

Brevoortia The genus ''Brevoortia'' are all species of menhaden, there are found mainly in western Atlantic and consist of the following species: * ''Brevoortia aurea'' (Spix & Agassiz, 1829) (Brazilian menhaden) * ''Brevoortia gunteri'' Hildebrand, 1948 ...

'' (menhadens), and '' Sardina''. The Alosidae were previously included in the herring family Clupeidae.

Genera

Alosidae contains the following 4 genera: *'' Alosa'' H. F. Linck, 1790 (Shads) *''

Gill A gill () is a respiration organ, respiratory organ that many aquatic ecosystem, aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow r ...

, 1861 (Menhadens) *'' Sardina'' Antipa, 1904 (European pilchard) *'' Sardinops'' C. L. Hubbs, 1929 (Blue pilchard) The following fossil Alosidae are also known: * †'' Eoalosa'' Marramà & Carnevale, 2017 (early Eocene of Italy) * †'' Moldavichthys'' Baykina & Schwarzhans, 2017 (mid-late Miocene of

Moldova Moldova, officially the Republic of Moldova, is a Landlocked country, landlocked country in Eastern Europe, with an area of and population of 2.42 million. Moldova is bordered by Romania to the west and Ukraine to the north, east, and south. ...

) * ?†'' Pugliaclupea'' Taverne, 2004 (Late Cretaceous of Italy) * †''

Sanalosa ''Sanalosa'' is an extinct genus of alosid that inhabited Poland during the Rupelian stage. It contains the species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or m ...

'' Bienkowska-Wasiluk, Granica & Kovalchuk, 2024 (Oligocene of Poland) The oldest member of the group is '' Pugliaclupea'' from the

Campanian The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campa ...

of Italy, but its placement in the Alosidae appears to be on weak grounds. Otherwise, all other members of the family are only known from the Eocene onwards. There appears to have been a significant center of

endemism Endemism is the state of a species being found only 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 foun ...

for the alosids and other clupeoids in the

Paratethys The Paratethys sea, Paratethys ocean, Paratethys realm or just Paratethys (meaning "beside Tethys"), was a large shallow inland sea that covered much of mainland Europe and parts of western Asia during the middle to late Cenozoic, from the lat ...

. The freshwater †'' Chasmoclupea'' from the

Oligocene The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that defin ...

of Egypt may also be related to the Alosidae.

Genera

See also

References