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Tubercles are also used to fight other males and defend and clean nests. Nest building males are larger than females, the reverse of the situation in most fishes where egg-bearing females are the largest.Not all species build nests and some simply broadcast eggs over weed, gravel or sand. This is a prolonged spawning season which ensures no single batch of eggs is lost to unfavourable, temporary environmental changes such as floods.(2002) as relicts of older colonization waves and show an eastern influence consistent with an Asian origin of the family Cyprinidae.Cyprinion has no sister species in the Euro-Mediterranean area and has been isolated in the Middle East since before the salinity crisis, 7.8-8.8 MY ago.The family is found in North America, Eurasia and Africa.
Generally males have longer pectoral fins than females.There are about 352 genera and over 2838 species (Nelson, 2006; Eschmeyer and Fong, 2011), about 8.9% of the world's fishes. 32 native genera (interpretations of genera differ between authors) and at least ?73 species (with more to be described) found in all the major drainage basins.The Middle East leuciscine cyprinids have Europe as an important Palearctic influence consistent with the Lago Mare dispersion while the the cyprinine cyprinids show three highly divergent lineages, namely one shared with the Euro-Mediterranean area (Barbus/Luciobarbus), a relict of the Lago Mare dispersion, one shared with Africa (Carasobarbus/Varicorhinus subgenus) and one with Asia (Garra).The Lago Mare dispersion occurred during a salinity crisis in the Mediterranean Sea 5.5 MY ago in the Late Miocene when freshwater fish were able to disperse through oligohaline or fresh water in the Paratethys Sea to reach the Middle East (Bianco, 1990). (2002) conflict with this scenario - the Carasobarbus clade that includes Barbus (= Tor) grypus shows a separation divergence later than the salinity crisis in the Pliocene when no migration route was available.