Genetic diversity, population structure and historical demography of the two-spined yellowtail stargazer (Uranoscopus cognatus)

Abstract

Benthic species, though ecologically important, are vulnerable to genetic loss and population size reduction due to impacts from fishing trawls. An assessment of genetic diversity and population structure is therefore needed to assist in a resource management program. To address this issue, the two-spined yellowtail stargazer (Uranoscopus cognatus) was collected within selected locations in the Indo-West Pacific (IWP). The partial mitochondrial DNA cytochrome c oxidase subunit 1 and the nuclear DNA recombination activating gene 1 were sequenced. Genetic diversity analyses revealed that the populations were moderately to highly diversified (haplotype diversity, H = 0.490–0.900, nucleotide diversity, π = 0.0010–0.0034) except sampling station (ST) 1 and 14. The low diversity level, however was apparent only in the matrilineal marker (H = 0.118–0.216; π = 0.0004–0.0008), possibly due to stochastic factors or anthropogenic stressors. Population structure analyses revealed a retention of ancestral polymorphism that was likely due to incomplete lineage sorting in U. cognatus, and prolonged vicariance by the Indo-Pacific Barrier has partitioned them into separate stock units. Population segregation was also shown by the phenotypic divergence in allopatric populations, regarding the premaxillary protrusion, which is possibly associated with the mechanism for upper jaw movement in biomechanical feeding approaches. The moderate genetic diversity estimated for each region, in addition to past population expansion events, indicated that U. cognatus within the IWP was still healthy and abundant (except in ST1 and 14), and two stock units were identified to be subjected to a specific resource management program.

Unraveling the Story of the Black Scorpionfish (Scorpaena porcus Linnaeus, 1758): Exploring Local Ecological Knowledge and the Exploitative History of a Marine Species

“…This alignment reinforces the reliability of LEK and affirms that both categories possess a keen perception of the historical and current medium size of the fish under investigation. The observed size reduction of S. porcus over time is likely attributed to the impacts of fishing activities, a suggestion consistent with findings by other author for various species [25]. However, other factors such as water warming cannot be dismissed, and might contribute, at least in part, to the decrease in fish body size, as proposed by some researchers [26,27].…”

First Evidence of Cryptic Species Diversity and Population Structuring of Selaroides leptolepis in the Tropical Western Pacific

“…Additional samples are necessary to quantify their degree of genetic variability. This type of delineation was also observed in Seriola nigrofasciata (Mat Jaafar et al, 2012), Lutjanus lutjanus (Bakar et al, 2018), Uranoscopus cognatus (Mohd Yusoff et al, 2021), and Penaeus semisulcatus (Halim et al, 2021).…”

Spatial Distribution and Genetic Diversity of Turbot (Scophthalmus maximus, Linnaeus, 1758) in Bulgarian Black Sea Waters Relative to Fishing Pressure and Their Abiotic Environment

“…The low haplotype and nucleotide diversity of the Tsarevo population (0.363 and 0.00139, respectively) was most likely the result of a founder event or population bottleneck [88]. Such low nucleotide diversity of the COI mitochondrial gene has been discovered in heavily exploited fish stocks (Lophius budegassa, Merluccius merluccius, Mullus barbatus, and Mullus surmuletus) from the Balearic Islands [7], and is typically leading to population bottleneck and a subsequent genetic reduction in the total gene pool [3].…”

“…The human overexploitation of natural resources has elevated conservation and management to one of modern society's most pressing concerns, particularly in the case of highly sensitive marine ecosystems [2]. Fishing is one of the most significant causes of decline in populations of ocean species [3]. In addition to depleting populations [4], overfishing can erode the age and size structure as well as the spatial distribution of stocks, making them more vulnerable to environmental fluctuations.…”