Mississipi River as a biogeographic barrier

I have recently visited the coastal plain of Florida, and found that many species of this region have disjunct populations either side of the mississipi, e.g.
Pinguicula pumila, Deirochelys reticularia (Chicken turtle), Nymphoides aquatica, Lyonia lucida, Chaptalia tomentosa, Burmannia biflora, Selaginella Arenicola, Quercus hemisphaerica (~), Quercus incana, Quercus minima

I was wondering if anybody knew anything about how this has happend?
This includes species from a wide range of habitats, e.g. Deirochelys reticularia (Chicken turtle) and Nymphoides aquatica are aquatic.
I can not find many papers on it other than this
(https://academic.oup.com/biolinnean/article/109/4/737/2415732)

If anybody has more information I would be very interested. It seems that a similiar ecosystem exists either side, but I am wondering about the effect of the Mississipi, e.g. destroying ecosystems when it re-routes, or as a barrier

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I edited the title to specify the river.

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What’s known as the “Mississippi Embayment” on a large biogeographic scale is well known to have separated and affected the distributions of plant and animal populations on either side of the river. Species of certain habitats like upland oak-hickory forest, or certain freshwater watersheds have long (for eons) been divided by the unsuitable floodplain habitats of the river basin and even incursions of the Gulf of Mexico based on the ups and downs of sea levels through the Pleistocene, etc. Some of the resultant separate populations just remain disjunct but conspecific, while others (e.g. some of the freshwater turtles and probably various fish) have speciated on either side of the embayment. It’s a fascinating topic with a large body of scientific literature. I would suggest doing a keyword search of Google Scholar with terms like “Mississippi Embayment”, “biogeography”, and “disjunct populations”.

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you might also check:
https://www.jstor.org/action/doBasicSearch?Query=“Mississippi+Embayment”

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There’s a paper here also:
https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-294X.2006.03061.x
Soltis, D. E., Morris, A. B., McLachlan, J. S., Manos, P. S., & Soltis, P. S. (2006). Comparative phylogeography of unglaciated eastern North America. Molecular ecology, 15(14), 4261-4293.

In addition to the Mississippi Discintinuity, there are others. The rivers themselves aren’t the barrier, it’s what was there thousands of years ago and how the species distributions shifted and then shifted back–often forming contact zones between groups that diverged during their isolation.

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Thank you for all the information! Sometimes just navigating the maze of the internet is difficult hahaha