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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.Collares-Pereira (1994) argues that the polyploid condition (e.g. There are 2-4 unbranched rays (including rudimentary ones) in the dorsal and anal fins followed by the more numerous branched rays (the last two branched rays are counted as one).The first pectoral and the first pelvic fin ray are unbranched and not included in counts.(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.
Tooth form varies with the food - molar-shaped teeth are used to crush molluscs, flat but grooved surfaces for grinding plant food and sharp edged teeth for slicing various invertebrate foods.
Pharyngeal teeth lie on a modified, fifth gill arch which can be seen or probed behind the shoulder girdle, just inside the gill opening.
The arch has to be removed with dissecting equipment to count the teeth.
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.
Teeth may be lost from major or minor rows so variant formulae are given after the principal one.