Across the highest mountain on earth: discordant phylogeographic patterns and recent dispersal of Tibetan stone loaches (Triplophysa) in the Himalayas

Abstract

Phylogeographic congruence among co‐distributed taxa is regarded as an inherent inference to vicariance events. Nonetheless, incongruent patterns of contemporary lineage divergence among taxa indicated that species differ in their response to common past events. To investigate the role of past events, ecological traits and lineage diversification time in shaping the contemporary phylogeographic patterns, comparative analyses were conducted for Tibetan stone loaches in the Himalayas using three gene markers and two ecological traits (depth of caudal peduncle in their length and presence/absence of posterior chamber of the air bladder). By a thorough sampling in two flanks of the Himalayas, the authors detected that phylogenetic breaks were spatially discordant and divergences of populations were also temporally asynchronous in co‐distributed loaches. Estimated divergence time using fossil‐calibrated node dating indicated that the Tibetan stone loaches colonised into the south flank of the Himalayas until the Pleistocene. The demographic expansions were also disconcerted between populations in north and south flanks, or east and west Himalayas. Ongoing gene flows between populations in north and south sides implied that the Himalayas do not strictly impede dispersal of cold‐adapted species. The results highlight that the quaternary climatic oscillation, in conjunction with ecological traits and lineage diversification time, shaped contemporary phylogenetic patterns of stone loaches in the Himalayas and provide new insights into the biodiversity and composition of species in the Himalayas and surrounding region.

Mitochondrial genome data provide insights into the phylogenetic relationships within Triplophysa dalaica (Kessler, 1876) (Cypriniformes, Nemacheilidae)

“…In the divergence-time analysis, these three clades were estimated to diverged 7–10 Ma. The divergence is relatively deep compared to the intraspecies differentiation in other Triplophysa species ( Hu et al 2020 , 2022 ; Wu et al 2020 ; Du et al 2023 ), suggesting they might be divided into several potential subspecies, or even species, which need extra analyses including morphology and phylogeny with more samples. These results offer insights into the evolutionary history of T. dalaica , as well as the correlation between the change of population and historical climate and geological events.…”

“…Due to their widespread distribution, species of Triplophysa exhibit adaptability to diverse habitats, including cold environments, hypoxia, and saline waters. In recent years, multiple aspects including the phylogenetic relationships among Triplophysa species ( Wang et al 2016 , 2023 ; Chen et al 2019 ; Wu et al 2020 ), phylogeography ( Hu et al 2020 , 2022 ; Zhong et al 2022 ; Du et al 2023 ), patterns of population differentiation ( Zhou et al 2021b ; Jin et al 2022 ), and the adaptations to various habitats ( Chen et al 2020b , 2020a ; Zhang et al 2023 ) have been studied.…”

Research advances in diversity and conservation science of freshwater fish in China

“…However, both numbers must be an underestimate, especially for the rare endemic species in upstream areas of rivers that are the most remote. This special issue includes four papers describing new records, new taxa, and phylogeny in China (Guo, Cao, and Zhang (2024); Hu et al, 2024; Li et al, 2024; Luo et al, 2024). Guo, Cao, and Zhang (2024) described two new Leptobotia spp.…”

“…Morphological and molecular approaches were used to describe a new cave species, Sinocyclocheilus xingyiensis in the southwest part of China (Luo et al, 2024), and to confirm a new record of Schizothorax richardsonii on the southern slope of the Central Himalayas where fish surveys have rarely been conducted (Li et al, 2024). Hu et al (2024) highlighted that the quaternary climatic oscillation, in conjunction with ecological traits and lineage diversification time, shaped contemporary phylogenetic patterns of stone loaches in the Himalayas.…”

“…Hu et al (2024) highlighted that the quaternary climatic oscillation, in conjunction with ecological traits and lineage diversification time, shaped contemporary phylogenetic patterns of stone loaches in the Himalayas. Five studies in this special issue focus on the biology and ecotoxicology of fishes in China.…”