Morphometric variation in the pharyngeal teeth of zebrafish (Danio rerio Cyprinidae) in response to varying diets

The purpose of this research project is to explore various aspects of pharyngeal dentition in relation to diet, focusing on one species. The fish I am interested in is Danio rerio (Hamifton-Buchanan), a cyprinid more commonly known as the zebrafish. Hamihon-Buchanan first described the genus Danio in 1822, but at that time it was recognized as a subgenus of Cyprinus and later was recognized as an independent genus Hamikon, 1822, Smith, 1945, Eschmeyer, 1990, Algharaibeh, 1997). In a later revision of the genus Danio (Weber & de Beaufort, 1916), the subgenus Brachydanio was erected to distinguish the small species of Danio. The eventual popularity of this new taxon became evident when it was given full generic status despite arguments that there is no valid reason to separate it from the original genus Danio. The major diagnostic differences between the two genera were based on the larger Danio species having a full or complete lateral line and more fin rays in the dorsal and anal fins (Sterba, 1967). This division was soon worked out and put to rest when Smith(1945) showed that some of the species allocated to Brachydanio, such as Danio shanensis, in fact exhibited complete lateral line systems (Algharaibeh, 1997). Other similar cases that have been described since then that have supported the concept of a single genus (e.g.. Barman, 1991), and these eventually aided in rejoining the two genera into the single original genus Danio.