Population genetic diversity and structure of Rhinogobius candidianus (Gobiidae) in Taiwan: Translocation and release.

Rhinogobius candidianus is a freshwater goby distributed in north, northwest, west, and south Taiwan, but this species has been introduced to east Taiwan and became dominant. To investigate its native population genetic diversity and structure and evaluate the sources and diversity of translocated populations, the mitochondrial DNA control region and cytochrome b gene (1981 bp) from 220 specimens were analyzed. These results indicated that (1) the east populations originated from two sources in west Taiwan; (2) translocated populations exist in east Taiwan and south Taiwan; (3) many populations have likely been moved secondarily by human intervention; (4) the effective size of the populations had declined greatly; (5) within the native populations, the ancestral populations colonized Taiwan during the land bridge phase in the Pleistocene through north Taiwan; (6) the landform changes in Taiwan shaped the population structure; and (7) the landforms of the coastline during glaciation also shaped the native range. The low-level genetic diversity, high population differentiation, and population decline greatly suggest the need for resource management and conservation interventions. Four clades (α-δ) should be managed as four distinct evolutionarily significant units, while the translocated populations should be managed as separate management units. Moreover, the translocated populations in east Taiwan should be evaluated and monitored carefully.

Genetic diversity of Rhinogobius delicatus (Perciformes: Gobiidae): origins of the freshwater fish in East Taiwan.

Mitochondrial DNA cytochrome b and d-loop sequences (1,984 bp) from 92 specimens of the freshwater goby Rhinogobius delicatus from seven drainages in East Taiwan were identified as two major lineages exhibiting a southern or northern distribution. The existence of low genetic diversity, a pattern of population decline and high population differentiation (FST=0.711) support the need for the development of management strategies for the conservation of localized populations. The results of a statistical dispersal-vicariance analysis suggested that the ancestral populations of R. delicatus were widely distributed in East Taiwan. Compared with the phylogeographic patterns of the other endemic eastern Taiwan freshwater fishes, Onychostoma alticorpus, Aphyocypris kikuckii and Hemimyzon taitungensis, our study suggests that the freshwater fishes colonized East Taiwan through northeastern and southwestern Taiwan, although the ancestral populations colonized the island before it reached its present shape.

Mitochondrial diversity and phylogeography of Acrossocheilus paradoxus (Teleostei: Cyprinidae).

Mitochondrial DNA cytochrome b sequences (1141 bp) in 229 specimens of Acrossocheilus paradoxus from 26 populations were identified as four lineages. The pairwise genetic distances among these four lineages ranged from 1.57 to 2.37% (mean= 2.00%). Statistical dispersal-vicariance analysis suggests that the ancestral populations were distributed over mainland China and Northern and Western Taiwan. Approximate Bayesian computation approaches show that the three lineages in Taiwan originated from the lineage in mainland China through three colonization routes during two glaciations. The results indicated that during the glaciation and inter-glacial periods, the Taiwan Strait was exposed and sank, which contributed to the dispersion and differentiation of populations. Furthermore, the populations of A. paradoxus colonized Taiwan through a land bridge to the north of the Formosa Bank, and the Miaoli Plateau in Taiwan was an important barrier that limited gene exchange between populations on both the sides.

The complete mitochondrial genome of Montipora aequituberculata (Scleractinia, Acroporidae).

The complete mitogenome of the hexacorallia, Montipora aequituberculata has been amplified and sequenced. The mitogenome consists of 17,886 bp, with 13 protein-coding genes, 2 ribosomal RNA genes, 2 transfer RNA genes and a control region. It has been observed that ND5 gene is split into two parts by a large fragment of genes, which commonly presented in scleractinian coral. The overall base composition of the H-strand was A, 24.91%; G, 24.1%; C, 14.2%; and T, 36.8%, with a slight AT bias of 61.7%. The control region was 627 bp in length and located between 12S rRNA and COIII gene. Based on the neighbour-joining (NJ) tree, M. aequituberculata was grouped with M. cactus, Anacropora matthai and Acropora tenuis, and formed a clade of Acroporidae. In conclusion, the complete mitogenome of M. aequituberculata data may provide more informative for phylogenetic approach for corals phylogeny.

The complete mitochondrial genome of variegated lizardfish Synodus variegatus (Aulopiformes, Synodontidae).

In this study, the complete mitogenome sequence of variegated lizardfish Synodus variegatus (Lacepède, 1803) (Perciformes, Synodontidae) has been amplified and sequenced employing the long polymerase chain reaction method. The mitogenome, consisting of 16,448 base pairs (bp), had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding, 22 transfer RNAs, 2 ribosomal RNAs genes and a noncoding control region (CR). The CR of 830 bp length is rather compact and located between tRNA(Pro) and tRNA(Phe). The overall base composition of Myxocyprinus asiaticus is 26.36% for A, 27.69% for C, 26.99% for T and 18.95% for G, with a slight AT bias of 53.36%. The complete mitogenome may provide important DNA molecular data for further phylogenetic analyses for higher taxa of teleost fishes, especially for the fishes of order Aulopiformes.