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Mitogenomics dataset for the Rasborinae of Sundaland

Hubert, Nicolas1

Published Mar 27, 2022 on Dryad. https://doi.org/10.5061/dryad.tb2rbp00g

Data files

Mar 27, 2022 version files 17.59 MB

Abstract

Aim: Eustasy has long been put forward to explain the colonization of Southeast Asian islands by freshwater aquatic organisms. We examined the relative impact of Sundaland geology since the Oligocene and of Pleistocene Eustatic Fluctuations on the mitochondrial lineage diversification of a species-rich subfamily of Cypriniformes fishes widely distributed in Southeast Asia, the Rasborinae. We specifically tested if variations in the extent of exposed lands and island connectivity during Pleistocene eustasy (the Paleoriver hypothesis) induced bursts of diversification.

Location: Sundaland

Taxon: Rasborinae (Actinopterygii, Cypriniformes, Danionidae)

Methods: We aggregated 1,017 cytochrome oxidase I sequences and 79 mitogenomes to delineate Molecular Operational Taxonomic Units (MOTUs) and further reconstruct a time-calibrated phylogeny of Rasborinae. Ancestral area estimations were conducted using both island and paleoriver partitioning to examine the impact of island connectivity during Pleistocene eustasy on dispersal. Temporal trends of diversification are explored through a model-based approach.

Results: The origin of Sundaland mitochondrial lineages is dated at ca. 33 Ma and four major clades are identified, which diversified between ca. 31 and 22 Ma. The Island of Borneo and North Sunda paleoriver are identified as the source of Sundaland Rasborinae. Geographical patterns of lineage divergence indicate that most divergence events occurred within islands and diversification under constant birth rate models are the most likely for all clades.

Conclusions: The geographical and historical context of diversification of mitochondrial lineages in Rasborinae provides little support for the Paleoriver Hypothesis. The onset of isolation of Borneo from mainland Asia triggered the initial diversification of the group (ca. 31-22 Ma). The late colonization of Java and Sumatra occurred through several independent dispersal events, poorly explained by Pleistocene eustasy, and frequently followed by in situ diversification.