Study On The Classification And Molecular Phylogeny Of Sparidae In China Seas

The perch family Sparidae (Osteichthyes: Perciformes) occur worldwide in coastal waters of tropical to temperate region. For their delicious taste and hearty nutrition, sparid fishes are very popular in China. They play an important role in the marine fishery resources and aquaculture. Due to their wide distribution and abundance in number of species, sparid fishes display a diversity of morphological characters. Concerning the classification and nomenclature, most problems arise from the great confusion due to the morphological similarities in the sparid fishes. It is always a difficult problem for taxonomists to clarify the species boundaries within very similar species based on the morphological characters and ecological habits. Some studies have been made on the taxonomy and phylogeny in several species of sparid fishes. However, the systematic and phylogenetic study of the sparid fishes in Chinese coastal waters is necessary.Based on the currently-known literature records, the present paper summarized the progress in the studies of classification and phylogeny of the sparid fishes, revised a lot of synonyms and errors, and determined the scientific name and valid species of Sparidae in China seas. A total of 16 species (or subspecies), belonging to 7 genera, are considered to be valid. Combined with available homologous squences of the sparid fishes from GenBank, sequences of parial mtDNA 16S rRNA gene and COâ… gene of 12 species 6 genus of sparid fishes in Chinese coastal waters are used to study the molecular phylogeny relationships, the main results are as follows:1. Six phylogenetic trees are reconstructed based on different models with the 16S rRNA sequence of Nemipterus marginatus and the COâ… sequence of Nemipterus japonicus as outgroup, the topology of them is almost the same. All genus are separated clearly. The genus Dentex, Pagrus, Evynnis and Argyrops which have the same red body color, are in one clade; another clade has the genus Acanthopagrus and Rhabdosargus which have the silver gray body color. The results show that the sparid fishes in the coastal waters of China separated by body color. In red body-color clade, the genus Dentex is the first division, followed by Argyrops, and Pagrus, Evynnis and Argyrops have a very close relationship; in silver gray body color clade, two genera also have a significant differentiation.2. The genetic distances between Pagrus and Evynnis based on 16S rRNA sequence and COâ… sequence using the mode kimura 2-parameter are 0.0178-0.0269 and 0.0721-0.0792, less than the genetic distance between other genera, even slightly less than the genetic distance between the species in genus Acanthopagrus. The result shows that the level of differentiation between these two genera only reached species differentiation. So the classification status of these two genera is needed further study.3. The samples of Acanthopagurs schlegelii schlegelii and A. schlegelii czerkii in all trees are non-monophyletic and the average genetic distances are 0.0005 and 0.0016, much less than other species in the genus Acanthopagrus. It indicates that A. schlegelii schlegelii and A. schlegelii czerkii are belonging to one species A. schlegelii, although they show great variations in body shape and color pattern.4. Pagrus major and Pagrus auratus, which are distributed in the Northwest Pacific and the coast of Australia and New Zealand respectively, were considered to be two different species in the past. In this study the genetic distances between them are 0.0071 and 0.0062-0.0093, far less than the genetic distance between the species in the genus Acanthopagurs. The results show that these two species don't reach the level of species differentiation, but they are clearly separated in one clade. Therefore, it was reasonable to infer that P. major distributing in coast of China is a subspecies of P. auratus major.5. Chinese sparid fishes consist 16 species or subspecies in 7 genera: Acanthopagrus australis, Acanthopagrus berda, Acanthopagrus chinshira, Acanthopagrus latus, Acanthopagrus schlegelii, Acanthopagrus sivicolus, Acanthopagrus taiwanensis, Argyrops bleekerii, Argyrops spinifer, Cheimerius matsubarai, Dentex abei, Dentex tumifrons, Evynnis cardinalis, Evynnis japonica, Pagrus auratus major and Rhabdosargu sarba. The morphological characters, habits and distributions of them are simply described, and a key to genera and species in the family Sparidae is provided in this paper.