Bitterling (Teleostei: Acheilognathinae) are small cyprinid fishes with a discrete distribution in East Asia and Europe. We used a complete mitochondrial cytochrome b sequence (1141 bp) from 49 species or subspecies in three genera (Tanakia, Rhodeus, and Acheilognathus), sampled across the major part of their distribution, to elucidate their phylogeny and biogeography, focusing particularly on their origin and dispersal. Based on high support value, the monophyletic Acheilognathinae separated into two major clades, Acheilognathus and Tanakia-Rhodeus. In the latter clade, the monophyly of Rhodeus was poorly supported, though it was topologically nested in Tanakia. On the basis of molecular-clock calibration, both clades diverged in the middle Miocene, with Tanakia-Rhodeus diverging slightly earlier than Acheilognathus. The Tanakia-Rhodeus clade expanded its distribution westward from the Far East, eventually reaching Europe, while Acheilognathus dispersed in the temperate regions of East Asia. A feature common to both clades is that most extant species, including Japanese endemics, appeared by the end of the Pliocene, corresponding with the present delineation of the Japanese archipelago. Autumn-spawning species with an embryonic diapause, unique to bitterling among cyprinid fishes, formed two distinct lineages (barbatulusrhombeus and longipinnis-typus) within Acheilognathus. The estimated time of divergence of the two lineages was approximately from the late Pliocene, a period characterized by glaciations. The timing of divergence suggests that the shift of spawning from spring to autumn, coupled with embryonic diapause, convergently emerged twice in the evolution of bitterling, possibly as an adaptation to the climate of the late Pliocene.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 31 • No. 5