Two new species of Rhinogobius (Gobiiformes: Oxudercidae) from Palawan, Philippines, with their phylogenetic placement

The complete mitochondrial genome of Rhinogobius maculagenys (Gobiidae:Gobionellinae)

The complete mitochondrial genome of Rhinogobius maculagenys Wu et al., (Perciformes,Gobiidae) was sequenced and annotated in this study. The circular mitogenome is 16,500 bp long and consists of 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes and two main non-coding regions (a putative control region and an L-strand replication origin). The overall base composition is 27.5% A, 25.5% T, 16.9% G, and 30.1% C. The gene order and composition are similar to those of other Gobionellinae species. Phylogenetic analysis revealed that R. maculagenys is closely related to Rhinogobius shennongensis in both the maximum likelihood tree and the Bayesian inference tree. The complete mitogenome of R. maculagenys will serve as a valuable resource for future studies on evolution, taxonomy, and genetic conservation of Rhinogobius.

Complete mitochondrial genome of Eonemachilus longidorsalis (Cypriniformes: Nemacheilidae): genome characterization and phylogenetic consideration

For the first time, this study presents the complete mitochondrial genome and phylogenetic analysis of Eonemachilus longidorsalis, an endemic species in southwest China. The mitogenome is a circular molecule of 16,569 bp in length with a base composition of 30.2% A, 27.3% T, 16.6% G, and 25.9% C. The phylogenetic analysis based on the complete mitogenomes shows that E. Longidorsalis clusters with Yunnanilus jiuchiensis, Yunnanilus pleurotaenia and Eonemachilus niger. This contribution may provide a valuable framework for completely resolving phylogenetic relationships of the family Nemacheilidae in future research.

Freshwater fishes of the Philippines: a provisional checklist

An updated checklist of freshwater fishes occurring in the Philippines is presented, with notes on their distribution and conservation status. Information was systematically and comprehensively reviewed, and compiled from current and historical sources including published literature, institutional reports, museum records, and online databases. Results indicate a total of 374 fish species within 29 orders and 78 families to occur in the country. Two hundred and twenty-five (60.16%) species are native, of which 85 (22.73%) are endemic; and an additional 64 (17.11%) are non-native. Gobiiformes is the most diverse order (114 species, 5 families), followed by Cypriniformes (54 species, 4 families) and Perciformes (28 species, 13 families). The most speciose family is Gobiidae (89 species), which represents 23.80% of the total fish diversity. Conservation status based on the IUCN Red List indicates that 57 (15.24%) fish species are assessed as "Data Deficient", 188 (50.27%) are "Least Concern", nine (2.41%) are "Near Threatened", 22 (5.88%) are "Vulnerable", 20 (5.35%) are "Endangered", 10 (2.67%) are "Critically Endangered", 15 (4.01%) are "Extinct", and the conservation status of a further 53 (14.17%) have not been assessed (Not Evaluated). The relatively high number of 'Data Deficient' species emphasizes the lack of information on the taxonomy, distribution, life history and population status of many species in the archipelago. Detailed studies on various aspects of the biology and threats is highly recommended to advance the scientific understanding of, and develop conservation plans for the freshwater fish species of Philippines.

The complete mitochondrial genome of Rhinogobius szechuanensis (Gobiiformes: Ggobiidae: Gobionellinae)

Here, we sequenced the complete mitogenome of Rhinogobius szechuanensis using the Illumina HiSeq platform and submitted the genome to Genbank with accession number OM617727. Assembly circular mitogenome (16,492 bp) consisted of 54.4% AT content, 13 protein-coding genes, 22 tRNA genes, two rRNA genes, an origin of light-strand replication, and a control region. Phylogenetic analysis supported that R. szechuanensis was grouped with R. rubromaculatus and clustered with other Rhinogobius species. The basal molecular data will be essential for further genetics studies such as evolution, taxonomy, DNA barcoding, and population genetics of Rhinogobius.

First complete mitochondrial genome of the endemic goby, Rhinogobius davidi (Gobiiformes: Gobiidae: Gobionellinae), in China

The first complete mitochondrial genome of the freshwater goby Rhinogobius davidi was determined by high-throughput sequencing. This genome was 16,627 bp in length and consisted of 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and 2 non-coding control regions. Phylogenetic analysis based on the amino acid sequences of 13 mitochondrial protein-coding genes from R. davidi and 23 relatives suggested that R. davidi had a close mitogenome relationship with Rhinogobius giurinus. This complete genome of R. davidi will provide basal molecular data for future studies on taxonomy, comparative genomics, and adaptive evolution in Rhinogobius.

Complete mitochondrial genome sequence and annotation of Rhinogobius lentiginis (Gobiiformes: Gobiidae: Gobionellinae)

We report the complete mitochondrial genome of Rhinogobius lentiginis, which was found to be a circular molecule of 16,633 bp in length and included 13 protein-coding genes (PCGs), 2 rRNA genes, 22 tRNA genes, and a non-coding control region. The overall base composition was 28.44% A, 26.21% T, 16.33% G, and 29.02% C. Phylogenetic analyses using maximum-likelihood and Bayesian inference methods revealed a close genome relationship among R. lentiginis, R. niger, R. shennongensis and R. maculagenys. The complete mitogenome of R. lentiginis will provide a valuable resource for species classification and conservation.

Characteristic and phylogenetic analyses of mitochondrial genome for Rhinogobius filamentosus (Teleostei: Gobiidae: Gobionellinae), an endemic species in China

This study sequenced and annotated the complete mitochondrial genome sequence of Rhinogobius filamentosus, an endemic species in China. The complete mitochondrial genome was 16,510 base pairs long and contained 13 protein-coding genes (PCGs, 11,414 bp), 22 tRNA genes (1,555 bp), two rRNA genes (2,615 bp), two non-coding regions (D-loop: control region displacement loop, 478 bp; OL: origin of L-strand replication, 30 bp). The overall base composition of the genome was estimated to be T (25.4%), C (30.2%), A (27.6%) and G (16.7%), showing an AT bias (53%). Phylogenetic analyses revealed that the genus Rhinogobius included two clades. For one clade, R. filamentosus clustered with R. duospilus, and they formed a sister-group relationship with other ten Rhinogobius species. This work would be essential in revealing the evolutionary relationships in Gobionellinae.