Project description:The complete mitochondrial genome of Gerres filamentosus was sequenced by high throughput sequencing method. Length of this genome is 16,795 bp, containing 13 protein-coding genes, 22 tRNA genes, two rRNA genes and one large non-coding region. ND6 and eight tRNA genes are encoded by L-strand, and others are encoded by H-strand, which is similar to those in most vertebrates. Phylogenetic tree based on 13 protein-coding genes shows that the clade of G. filamentosus is closely clustered with that of Gerres oyena, and families Caproidae and Ephippidae have the closest relationship to Gerridae, comparing with Sillaginidae.
Project description:In the tropical Indo-Pacific, most phylogeographic studies have focused on the shallow-water taxa that inhabit reefs to approximately 30 m depth. Little is known about the large predatory fishes, primarily snappers (subfamily Etelinae) and groupers (subfamily Epinephelinae) that occur at 100-400 m. These long-lived, slow-growing species support fisheries across the Indo-Pacific, yet no comprehensive genetic surveys within this group have been conducted. Here we contribute the first range-wide survey of a deepwater Indo-Pacific snapper, Pristipomoides filamentosus, with special focus on Hawai'i. We applied mtDNA cytochrome b and 11 microsatellite loci to 26 samples (N=1,222) collected across 17,000 km from Hawai'i to the western Indian Ocean. Results indicate that P. filamentosus is a highly dispersive species with low but significant population structure (mtDNA Φ(ST)=0.029, microsatellite F(ST)=0.029) due entirely to the isolation of Hawai'i. No population structure was detected across 14,000 km of the Indo-Pacific from Tonga in the Central Pacific to the Seychelles in the western Indian Ocean, a pattern rarely observed in reef species. Despite a long pelagic phase (60-180 days), interisland dispersal as adults, and extensive gene flow across the Indo-Pacific, P. filamentosus is unable to maintain population connectivity with Hawai'i. Coalescent analyses indicate that P. filamentosus may have colonized Hawai'i 26 K-52 K y ago against prevailing currents, with dispersal away from Hawai'i dominating migration estimates. P. filamentosus harbors low genetic diversity in Hawai'i, a common pattern in marine fishes, and our data indicate a single archipelago-wide stock. However, like the Hawaiian Grouper, Hyporthodus quernus, this snapper had several significant pairwise comparisons (F(ST)) clustered around the middle of the archipelago (St. Rogatien, Brooks Banks, Gardner) indicating that this region may be isolated or (more likely) receives input from Johnston Atoll to the south.
Project description: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.
Project description:Due to the presence of different parasite taxa and other disease-causing agents, all fish species are extremely prone to dangers. As a result, the current study focused on some of the monogenean parasites that infect one of the economically important fish species, the soldier bream Argyrops filamentosus, from the Red Sea coast of Jeddah, Saudi Arabia. Following that, thirty A. filamentosus fish specimens were examined for monogenean parasites. The parasitic species were isolated and morphologically and molecularly studied. The presence of one monogenean species of Haliotrema susanae (F: Ancyrocephalidae) infecting gills was observed in 50% of the investigated fish species. The ancyrocephalid species Haliotrema susanae is characterized by having all generic features within the genus Haliotrema. It could be distinguished from other species within this genus by the male copulatory organ including a copulatory tube with no accessory piece and a haptor made up of two pairs of anchors, two bars, and seven pairs of marginal hooks. As ectoparasitic taxa of the investigated sparid fish, the current study of Haliotrema species constitutes the first report of this genus. A molecular phylogenetic analysis based on the partial 28S rRNA gene region was analyzed to investigate the phylogenetic affinity of this parasite with the genus Haliotrema belonging to Ancyrocephalidae. This study considers the addition of a new genetic sequence for this parasite species.
