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Tooth counts are presented as a formula such as 2,5-4,1 which indicates 2 teeth in the outer left row and 4 on the inner right row.
The arch has to be removed with dissecting equipment to count the teeth.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.Nuptial, pearl or breeding tubercles develop on the head, scales and fin rays often in distinct patterns, and there are swellings of the head or fin rays in some species. Tubercles and swollen rays are used to clasp females during the spawning act.Generally males have longer pectoral fins than females.Cyprinion may have entered the Middle East during the colonization event that isolated the genera Barbus sensu lato and Schizothorax in the European and Asian basins respectively.
The divergence of these species is similar in time to the radiation of the Leuciscinae supposedly centred in Siberia based on fossil records. (sic) from the Lower Miocene of Saudi Arabia showing an early date for the entry of cyprinids to the Afro-Arabian Plate.
The minnow or carp family is comprised of small to very large fishes (1 cm and up to 3 m, with some of the largest members in Iran) characterised by throat or pharyngeal teeth in 1-3 rows, with a maximum of 8 teeth in a row, tooth counts and form are often characteristic of the genus or species, no jaw teeth, body form various from fusiform to compressed, lips are usually thin and not sucker-like (but can show hypertrophy), the upper jaw is bordered by the premaxillae bones and usually protrusible, barbels are absent or present in 1-3 pairs (not more than 2 pairs in Iranian species), body covered in cycloid scales, in some species easily lost, while the head is scaleless, no adipose fin, the anterior 4 vertebrae are modified for conduction of sound from the air bladder to the ear and are known as the Weberian apparatus, pelvic fins are abdominal in position, no pyloric caeca, air bladder usually present and well-developed, connected to the gut by a duct, and not enclosed in a bony capsule, no true stomach, branchiostegal rays always 3 in number, no true spines in the fins although in some the last branched dorsal fin ray (at the front of the fin) may be thickened and spine-like and in Cyprinus and Carassius the last unbranched anal ray is also thickened.
The primitive chromosome number is 2n=50 but polyploidy is common and seen in Cyprinus, Carassius and in the schizothoracines.
Two subfamilies, the Alburninae and Leuciscinae, are paraphyletic but together seem to form a monophyletic group with a radiation about 20 million years ago, based on allozyme, cytochrome b, 16S r DNA and mitochondrial control region data from European cyprinids (Hnfling and Brandl, 2000; Gilles et al., 2001). Zardoya and Doadrio (1999) analysed the cytochrome b nucleotide sequence of a variety of cyprinids, mostly European, and found support for two subfamilies Cyprininae (including barbins) and Leuciscinae (including cultrins, tincins, gobionins, phoxinins and alburnins leuciscins).
The origin of cyprinids is estimated at 38.9MYA and the separation of Cyprininae and Leuciscinae at 27.7MYA.
Carps are mostly omnivores, feeding on small crustaceans, insects and some minute plants but some specialise in eating large plants, or other fishes.