Phylogeographic and evolutionary history analyses of the warty crab Eriphia verrucosa (Decapoda, Brachyura, Eriphiidae) unveil genetic imprints of a late Pleistocene vicariant event across the Gibraltar Strait, erased by postglacial expansion and admixture among refugial lineages

Abstract

Background The Pleistocene cyclic sea-level fluctuations are thought to have markedly affected the distribution and genetic architecture of Atlanto-Mediterranean biota. Despite the acknowledged key role played by these historical events in shaping population genetic structure of marine species, little is still known about the processes involved in shaping the spatial distribution of genetic variation within intertidal species. We intended in this study to reconstruct the phylogeography of a common and widely distributed coastal species across the East Atlantic and Mediterranean Sea (the warty crab Eriphia verrucosa ), aiming to unravel potential microevolutionary processes likely involved in shaping its genetic polymorphism. For this purpose, a total of 155 specimens of E. verrucosa from 35 locations across the entire distribution range were analyzed by comparing a 453 basepairs region of the mitochondrial gene cytochrome oxidase subunit 1 (Cox1). Results Our results unveiled the prevalence of high genetic connectivity among East Atlantic and Mediterranean populations, with noticeable genetic distinctiveness of the peripheral population from the Azores. Spatio-temporal patterns of genetic diversification and demographic history allowed retrieving genetic imprints of late Pleistocene vicariant event across the Gibraltar Strait followed by subsequent postglacial expansion events for both the East Atlantic and Mediterranean regions. Integrative evidences from the outcomes of comparison of regional genetic diversification, as well as evolutionary and biogeographic histories reconstructions, support the existence of potential glacial refugia for E. verrucosa in the East Atlantic and western Mediterranean. Our results also revealed low levels of genetic variability along with recent demographic and spatial expansion events for eastern Mediterranean warty crabs, suggesting that the eastern areas within the distribution range of the species might have been recently colonized from putative glacial refugia. Conclusions These findings provide new insights into the phylogeography and evolutionary history of a common but poorly studied Atlanto-Mediterranean decapod species. Specifically, they contribute to the understanding of the impact of historical processes on shaping contemporary population genetic structure and diversity in intertidal marine species. Electronic supplementary material The online version of this article (10.1186/s12862-019-1423-2) contains supplementary material, which is available to authorized users.

Localized environmental heterogeneity drives the population differentiation of two endangered and endemic Opisthopappus Shih species

“…Moreover, the environments (including temperature and precipitation) for each population was diversified due to the variable localized climates of the Taihang Mountains. This situation enabled these isolated subpopulations to eventually evolve into genetically distinct lineages via the accumulation of genetic differences and adaptations to local environments [16,17,54]. The adaptive divergence between populations was typically initiated by single or simple environmental differences, followed by the expansion of accumulating genetic divergence [5,[55][56][57].…”

“…Climate fluctuations would further promote differentiation between haplotypes or species.Additionally, the most recent diversification of haplotypes within species occurred primarily during the Quaternary glacial period (Fig. 4), which had a considerable impact on the distribution of modern animals and plants [16,[63][64][65]. Glacial and interglacial cycles played significant roles in the formation and differentiation of species.…”

“…During this process, intensifying climate change had left an indelible imprint on the composition and divergence of populations or species [15,16], which further greatly influenced the distribution patterns and shaped the genetic structures of populations [5,17]. In general, the geographical processes of mountainous regions may influence the genetic makeup of plant populations over large spatial scales, whereas ecological processes from climate change may influence the genetic structures of plant populations at small spatial scales [5,[18][19][20].…”

Localized environmental heterogeneity drives the population differentiation of two endangered and endemic Opisthopappus Shih species

“…In turn, these environmentally distinct habitats can serve as a barrier to gene flow, causing genetic differentiation between spatially close populations [ 47 ]. Consequently, these would promote isolated subpopulations to eventually evolve into genetically distinct lineages, while adapting to local environments [ 16 , 17 , 55 ].…”

“…During this process, intensifying climate change has left an indelible imprint on the composition and divergence of populations or species [ 15 , 16 ], which further greatly influenced the distribution patterns and shaped the genetic structures of populations [ 5 , 17 ]. In general, the geographic processes of mountainous regions may influence the genetic makeup of plant populations over large spatial scales, whereas ecological processes from climate change may impact the genetic structures of plant populations at small spatial scales [ 5 , 18 – 20 ].…”