A phylogenetic analysis of rasborin fishes (Teleostei, Cyprinidae)

Sammanfattning: The Danioninae (sensu lato) were until recently considered to be a paraphyletic group, comprising about 200 species and distributed over Africa and southern and eastern Asia. There was no morphological diagnosis for the Danioninae, and also the composition of the subfamily, and the interrelationships of included genera have been contentious. I have analysed morphological and DNA data from nearly all Asian genera and a few African genera of Danioninae (sensu stricto) with the objective of elucidating in particular the interrelationships among species of the large genus Rasbora, and the relationship of this genus to other danionines. Character optimization show the long intercostal ligament to be a synapomorphy of the Cypriniformes and the Cyprinidae to be diagnosed by the presence of the Y-shaped ligament, connecting the kinethmoid and mesethmoid. The Danioninae, however, are characterized by the absence of the Y-shaped ligament, here interpreted as a secondary loss. Phylogenetic analyses using morphological and molecular data show that the Danioninae are monophyletic with the exclusion of a group of East Asian species, now recognized as the Opsariichthyinae. By the exclusion of the Opsariichthyinae, the East Asian extension of the Danioninae becomes limited to the Pearl River basin in southern China. A phylogenetic analysis of the Middle East species Barilius mesopotamicus confirms that it is an Asian species of the Danioninae. The Asian distribution of the Danioninae is thus expanded from southeastern Iran to the Tigris-Euphrates River basin. Danioninae (sensu stricto) fall into three major groups, the Rasborini, and the Danionini with subtribes Danionina and Chedrina. The danionin foramen, a foramen in the cleithrum, is a synapomorphy of the Danionina. The Chedrina are characterized by the postcleithrum absent or greatly reduced. The rasborin process, a small process on epibranchial 4, is a synapomorphy of the Rasborini. The morphological phylogenetic analysis suggests the presence of an opercular canal as a synapomorphy of Rasbora, but this is not corroborated by the molecular phylogenetic analysis. In the molecular phylogenetic analysis the distribution of species of Rasbora largely falls into two areas, viz., the Indian region, and the Indo-Malayan region, divided by the western Shan Plateau and the Tenasserim Range. Morphological and molecular phylogenetic analyses of the Danioninae resulted in the discovery of seven new genera, five rasborins and two danionins, and one new danionin species.