Synodontis

''Synodontis'' is the largest genus of mochokid catfishes. It is the biggest genus within the 10 genera and 190 different species in the family Mochokidae. ''Synodontis'' has over 131 different species within the genus. ''Synodontis'' are also known as squeakers, due to their ability to make stridulatory sounds through their pectoral fin spines when handled or disturbed. ''Synodontis'' make a sound that sounds like squeaking by rubbing their spines together. They do this when they have been frightened or when they become angry. ''Synodontis'' may also squeak when they are taken out of the water. These catfish are small- to medium-sized fish with many species exhibiting attractive spotted markings. Some species are also known for naturally swimming belly-up, earning the name upside-down catfish. Some of these species are '' Synodontis contractus'' and '' Synodontis nigriventris''. While some of these species are known to swim upside down, another species, '' Synodontis multipunctatus'', is a brood parasitic cuckoo catfish,there are two other species Synodontis petricola and Synodontis grandiops are also called brood parasitic cuckoo catfish.

Distribution

''Synodontis'' is a freshwater catfish that is most commonly found throughout Africa, occurring mostly in Central and West Africa. ''Synodontis'' is the most widely distributed mochokidae genus, occurring throughout most of the freshwaters of sub- Saharan Africa and the Nile River system. They can live in freshwaters which can be creeks, ponds, streams, lakes, and rivers. Their distribution is similar to that of cichlid fishes, however, unlike cichlids the majority of their diversity occurs in rivers not lakes.

Evolutionary history

''Synodontis'' catfish form a small endemic radiation in Lake Tanganyika, which includes the non-endemic species ''S. victoriae''. This radiation is thought to have evolved relatively recently (~5.5. Million years ago), having diversified within full lacustrine conditions. This is also the case for other endemic Lake Tanganyika lineages such as mastacembelid eels and platythelphusid crabs for example. Lake Tanganyikan ''Synodontis'' have also been shown to be Müllerian mimics, and that at least one species (''Synodontis multipunctatus'') is a brood parasite.

Fossil record

The earliest fossils of ''Synodontis'' in East African are from the Early Miocene. Many ''Synodontis'' fossils are the spines because they are very sturdy and so they are preserved better. The fossils of spines that are found are used to determine the family or genera of the fish but it cannot determine the species. ''Synodontis'' species that have survived and are still living can be identified by the shape of their whisker like organs on their heads called barbels, which relate to touch. The can also be identified by the color of their skin, the skull bones, and the number and length of the teeth.

Ecology

''Synodontis'' species are omnivorous generalists, feeding on a wide spectrum of different foods and are largely unspecialized. Insects, crustaceans, mollusks, annelids, seeds, and algae have been found in the stomachs of different species of ''Synodontis''. They are bottom-feeders and may be detritivores, some species may also be able to adapt to filter feeding. This allows them to cope with seasonal and habitat changes and gives them a better ability to colonize different habitats. Different ''Synodontis'' species have somewhat different growth rates but most of them are fairly similar. Females of a species are generally larger than the males. There is a great increase in growth the first year in both male and female and then the growth slows down as they become older. The form and structure of these fish are very different compared to other fish. The size and shape of the mouth are distinct because of its ventral mouth and these fish usually are triangular or cylindrical when looking at it from the side. Not much is known about the reproduction in these fish. It has been determined that July to October is when they spawn and that they swim in pairs during this spawning time. Species of ''Synodontis'' have been noted to reproduce with the flooding period of the rainy season.

Relationship to humans

Many ''Synodontis'' species are prized ornamental fish in the fishkeeping hobby. While some of the ''Synodontis'' species are prized because of their color or behavior, other species are wanted for food. Some of the bigger species in the genus are important food sources for the people in Africa.

Species

There are currently 131 recognized species in this genus: ''Synodontis'' accounts for about one-quarter of African catfish species. This genus has more members than any other African teleost genus other than ''Barbus'' and ''Haplochromis''.

Newer species are listed with references.

* '' Synodontis acanthomias'' Boulenger, 1899
* '' Synodontis acanthoperca'' Friel & Vigliotta, 2006
* '' Synodontis afrofischeri'' Hilgendorf, 1888 (Fischer's Victoria squeaker)
* '' Synodontis alberti'' Schilthuis, 1891 (Bigeye squeaker)
* '' Synodontis albolineatus'' Pellegrin, 1924
* '' Synodontis angelicus'' Schilthuis, 1891 (Angel squeaker)
* '' Synodontis annectens'' Boulenger, 1911
* '' Synodontis ansorgii'' Boulenger, 1911
* '' Synodontis arnoulti'' Román, 1966
* '' Synodontis aterrimus'' Poll & Roberts, 1968
* '' Synodontis bastiani'' Daget, 1948
* '' Synodontis batensoda'' Rüppell, 1832 (Upsidedown catfish)
* '' Synodontis batesii'' Boulenger, 1907
* '' Synodontis brichardi'' Poll, 1959
* '' Synodontis budgetti'' Boulenger, 1911
* '' Synodontis camelopardalis'' Poll, 1971
* ''Synodontis carineae'' Vreven & Ibala Zamba, 2011
* '' Synodontis caudalis'' Boulenger, 1899
* '' Synodontis caudovittatus'' Boulenger, 1901
* '' Synodontis centralis'' Poll, 1971
* '' Synodontis clarias'' (Linnaeus, 1758) (Mandi)
* '' Synodontis comoensis'' Daget & Lévêque, 1981
* '' Synodontis congicus'' Poll, 1971
* '' Synodontis contractus'' Vinciguerra, 1928 (Bugeye squeaker)
* '' Synodontis courteti'' Pellegrin, 1906
* '' Synodontis cuangoanus'' Poll, 1971
* '' Synodontis decorus'' Boulenger, 1899 (Clown squeaker)
* '' Synodontis dekimpei'' Paugy, 1987
* '' Synodontis depauwi'' Boulenger, 1899
* '' Synodontis dhonti'' Boulenger, 1917
* '' Synodontis dorsomaculatus'' Poll, 1971
* '' Synodontis eupterus'' Boulenger, 1901 (Featherfin squeaker)
* '' Synodontis filamentosus'' Boulenger, 1901
* '' Synodontis flavitaeniatus'' Boulenger, 1919 (Orangestriped squeaker)
* '' Synodontis frontosus'' Vaillant, 1895
* '' Synodontis fuelleborni'' Hilgendorf & Pappenheim, 1903 (Fuelleborn's squeaker)
* '' Synodontis geledensis'' Günther, 1896 (Geledi squeaker)
* '' Synodontis gobroni'' Daget, 1954
* '' Synodontis grandiops'' Wright & Page, 2006
* '' Synodontis granulosus'' Boulenger, 1900
* '' Synodontis greshoffi'' Schilthuis, 1891
* '' Synodontis guttatus'' Günther, 1865
* '' Synodontis haugi'' Pellegrin, 1906
* ''Synodontis ilebrevis'' Wright & Page, 2006
* '' Synodontis irsacae'' Matthes, 1959
* '' Synodontis iturii'' Steindachner, 1911
* '' Synodontis katangae'' Poll, 1971
* '' Synodontis khartoumensis'' Abu Gideiri, 1967
* '' Synodontis koensis'' Pellegrin, 1933
* '' Synodontis kogonensis'' Musschoot & Lalèyè, 2008
* '' Synodontis laessoei'' Norman, 1923
* '' Synodontis leopardinus'' Pellegrin, 1914 (Leopard squeaker)
* ''Synodontis leopardus'' Pfeffer, 1896
* ''Synodontis levequei'' Paugy, 1987
* ''Synodontis longirostris'' Boulenger, 1902
* '' Synodontis longispinis'' Pellegrin, 1930
* ''Synodontis lucipinnis'' Wright & Page, 2006
* '' Synodontis lufirae'' Poll, 1971
* '' Synodontis macrophthalmus'' Poll, 1971
* '' Synodontis macrops'' Greenwood, 1963
* '' Synodontis macropunctatus'' Wright & Page, 2008
* '' Synodontis macrostigma'' Boulenger, 1911 (Largespot squeaker)
* '' Synodontis macrostoma'' Skelton & White, 1990 (Largemouth squeaker)
* '' Synodontis manni'' De Vos, 2001 (Feather-barbelled squeaker)
* '' Synodontis marmoratus'' Lönnberg, 1895
* '' Synodontis matthesi'' Poll, 1971
* '' Synodontis melanopterus'' Boulenger, 1903
* '' Synodontis melanostictus'' Boulenger, 1906
* '' Synodontis membranacea'' ( Geoffroy Saint-Hilaire, 1809)
* '' Synodontis multimaculatus'' Boulenger, 1902
* '' Synodontis multipunctatus'' Boulenger, 1898 (Cuckoo catfish)
* '' Synodontis nebulosus'' Peters, 1852 (Cloudy squeaker)
* '' Synodontis ngouniensis'' De Weirdt, Vreven & Fermon, 2008
* '' Synodontis nigrita'' Valenciennes, 1840
* '' Synodontis nigriventris'' David, 1936 (Blotched upsidedown catfish)
* '' Synodontis nigromaculatus'' Boulenger, 1905 (Blackspotted squeaker)
* '' Synodontis njassae'' Keilhack, 1908 (Malawi squeaker)
* '' Synodontis notatus'' Vaillant, 1893 (Onespot squeaker)
* '' Synodontis nummifer'' Boulenger, 1899
* ''Synodontis obesus'' Boulenger, 1898
* '' Synodontis ocellifer'' Boulenger, 1900
* '' Synodontis omias'' Günther, 1864
* '' Synodontis orientalis'' Seegers, 2008
* '' Synodontis ornatipinnis'' Boulenger, 1899
* '' Synodontis ornatissimus'' Gosse, 1982
* '' Synodontis ouemeensis'' Musschoot & Lalèyè, 2008
* '' Synodontis pardalis'' Boulenger, 1908
* '' Synodontis petricola'' Matthes, 1959 (Cuckoo Catfish)
* '' Synodontis pleurops'' Boulenger, 1897 (Congo squeaker)
* '' Synodontis polli'' Gosse, 1982
* '' Synodontis polyodon'' Vaillant, 1895
* '' Synodontis polystigma'' Boulenger, 1915
* ''Synodontis pulcher'' Poll, 1971
* '' Synodontis punctifer'' Daget, 1965
* '' Synodontis punctulatus'' Günther, 1889
* '' Synodontis punu'' Vreven & Milondo, 2009
* '' Synodontis rebeli'' Holly, 1926
* '' Synodontis resupinatus'' Boulenger, 1904
* '' Synodontis ricardoae'' Seegers, 1996 (Ricardo's squeaker)
* '' Synodontis robbianus'' Smith, 1875
* '' Synodontis robertsi'' Poll, 1974
* '' Synodontis ruandae'' Matthes, 1959
* '' Synodontis rufigiensis'' Bailey, 1968
* ''Synodontis rukwaensis'' Hilgendorf & Pappenheim, 1903 (Lake Rukwa squeaker)
* '' Synodontis schall'' ( Bloch & Schneider, 1801) (Wahrindi)
* '' Synodontis schoutedeni'' David, 1936
* '' Synodontis serpentis'' Whitehead, 1962 (Tana squeaker)
* '' Synodontis serratus'' Rüppell, 1829
* '' Synodontis smiti'' Boulenger, 1902
* '' Synodontis soloni'' Boulenger, 1899
* '' Synodontis sorex'' Günther, 1864
* '' Synodontis steindachneri'' Boulenger, 1913
* ''Synodontis tanganyicae'' Borodin, 1936
* '' Synodontis tessmanni'' Pappenheim, 1911
* '' Synodontis thamalakanensis'' Fowler, 1935
* '' Synodontis thysi'' Poll, 1971
* '' Synodontis tourei'' Daget, 1962
* '' Synodontis unicolor'' Boulenger, 1915
* '' Synodontis vaillanti'' Boulenger, 1897
* '' Synodontis vanderwaali'' Skelton & White, 1990
* '' Synodontis velifer'' Norman, 1935
* '' Synodontis vermiculatus'' Daget, 1954
* '' Synodontis victoriae'' Boulenger, 1906 (Lake Victoria squeaker)
* ''Synodontis violaceus'' Pellegrin, 1919
* '' Synodontis voltae'' Román, 1975
* '' Synodontis waterloti'' Daget, 1962
* '' Synodontis woleuensis'' Friel & Sullivan, 2008
* '' Synodontis woosnami'' Boulenger, 1911 (Upper Zambezi squeaker)
* '' Synodontis xiphias'' Günther, 1864
* '' Synodontis zambezensis'' Peters, 1852 (Plain squeaker)
* '' Synodontis zanzibaricus'' Peters, 1868 (Eastcoast squeaker)

References

{{Taxonbar, from=Q209386

Fish of Africa
Catfish genera
Taxa named by Georges Cuvier
Freshwater fish genera