Matrilineal evidence for genetic structure and Late Pleistocene demographic expansion of the Ornate goby Istigobiusornatus (Teleostei: Gobiidae) in the Persian Gulf and Oman Sea

Abstract

The Persian Gulf and Oman Sea are characterized by an interesting paleoclimatic history and different ecological settings, and offer a unique study area to investigate the genetic structure of marine organisms including fishes. The Ornate goby Istigobius ornatus is widely distributed throughout the tropical Indo‐West Pacific including the Persian Gulf and Oman Sea. Here, we present the population structure, genetic diversity, and demographic history of four populations of I. ornatus from the latter two regions using the D‐loop marker of mitochondrial DNA. The results reveal a shallow genealogy, a star‐like haplotype network, significance of neutrality tests, and unimodal mismatch distribution. This is concordant with a recent demographic expansion of I. ornatus in the Persian Gulf and Oman Sea at about 63,000–14,000 years ago, which appears to be related to Late Pleistocene sea level fall and rise. The results of the pairwise Fst estimates imply high gene flow along the coast of the Persian Gulf, which is probably due to larval dispersion, whereas the Oman Sea population clearly differs from all Persian Gulf populations. The AMOVA result indicates that 7.74% of the variation is related to differences among ecoregions, while inter‐ and intra‐population differences explained −3.20% and 95.47% of the variation, respectively. The haplotype network depicts two groups of haplotypes, most of them were specific to the Persian Gulf. No further evidence for geographic lineage substructuring was evident. The Mantel test result indicates that isolation by distance is not the main mechanism that promoted the genetic differentiation among the studied populations of I. ornatus. We suggest that cumulative effects of ecological and geographic barriers such as salinity, oceanographic conditions, and the presence of the Strait of Hormuz have shaped the genetic structure of I. ornatus in the Persian Gulf and Oman Sea.

Morphological and microstructural characteristics of scales in longnose goby Awaous jayakari (Teleostei: Gobiidae): Light and scanning electron microscopy approaches

“…Gobiids (family Gobiidae) have also been subjected to various morphological, biological, and molecular studies (e.g., Goren, 1979; Kovačić, Sadeghi, & Esmaeili, 2020; Lindstrom, Blum, Walter, Gagne, & Gilliam, 2012; Sadeghi & Esmaeili, 2019a, 2019b; Sadeghi, Esmaeili, Teimori, Ebrahimi, & Gholamhosseini, 2020; Sadeghi, Esmaeili, Zarei, & Reichenbacher, 2021). However, LM and SEM data on the detailed structure of scales for several gobies including members of the genus Awaous have not been provided.…”

“…F I G U R E 3 General shape and morphological details of key scale in large specimen (L2), SL = 109 mm. (a) Scale shape and surface morphology, (b) focus position in scale, (i) lepidonts, (c) focus shape, (d) left side of scale, (e, g) circuli of lateral field, (f) right side of scale, and (h) rostral lepidonts Gobiids (family Gobiidae) have also been subjected to various morphological, biological, and molecular studies (e.g., Goren, 1979; Kovac ˇi c, Lindstrom, Blum, Walter, Gagne, & Gilliam, 2012;Sadeghi & Esmaeili, 2019a, 2019bSadeghi, Esmaeili, Teimori, Ebrahimi, & Gholamhosseini, 2020;Sadeghi, Esmaeili, Zarei, & Reichenbacher, 2021). However, LM and SEM data on the detailed structure of scales for several gobies including members of the genus Awaous have not been provided.…”