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Abstract Obovaria olivariais a species of freshwater mussel native to the Mississippi River and Laurentian Great Lakes‐St. Lawrence River drainages of North America. This mussel has experienced population declines across large parts of its distribution and is imperiled in many jurisdictions.Obovaria olivariauses the similarly imperiledAcipenser fulvescens(Lake Sturgeon) as a host for its glochidia. We employed mitochondrial DNA sequencing and restriction site‐associated DNA sequencing (RAD‐seq) to assess patterns of genetic diversity and population structure ofO. olivariafrom 19 collection locations including the St. Lawrence River drainage, the Great Lakes drainage, the Upper Mississippi River drainage, the Ohioan River drainage, and the Mississippi Embayment. Heterozygosity was highest in Upper Mississippi and Great Lakes populations, followed by a reduction in diversity and relative effective population size in the St. Lawrence populations. PairwiseFSTranged from 0.00 to 0.20, and analyses of genetic structure revealed two major ancestral populations, one including all St. Lawrence River/Ottawa River sites and the other including remaining sites; however, significant admixture and isolation by river distance across the range were evident. The genetic diversity and structure ofO. olivariais consistent with the existing literature onAcipenser fulvescensand suggests that, although northern and southernO. olivariapopulations are genetically distinct, genetic structure inO. olivariais largely clinal rather than discrete across its range. Conservation and restoration efforts ofO. olivariashould prioritize the maintenance and restoration of locations whereO. olivariaremain, especially in northern rivers, and to ensure connectivity that will facilitate dispersal ofAcipenser fulvescensand movement of encysted glochidia.
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Phylogeography of the imperiled Comanche Harvester Ant (Pogonomyrmex comanche)
One of the few imperiled ant species in North America is the Comanche Harvester Ant, Pogonomyrmex comanche. Despite its status, little is known about its natural history throughout its range in the western Gulf Coastal Plain of North America. This study presents a regional phylogeographic analysis of P. comanche across sites in its natural range as a first step to learning more about this species. By using COI genotyping, we discovered that the center of genetic diversity is found in central Texas, which is typical for many species that found refugia in the southern North America during Pleistocene glaciations. Although diversity was slightly lower in northern populations, there was no evidence of recent population expansion into northern latitudes. Rather, some deviations from neutrality were consistent with population contraction in the northern regions (Arkansas, Oklahoma). The high diversity and relative rarity of identical sequences among samples were also consistent with dispersal limitation. The exact mechanisms driving its decline are currently unknown, but a combination of dispersal limitation and habitat loss seem likely causes.
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- Award ID(s):
- 2230334
- PAR ID:
- 10535628
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Insectes Sociaux
- Edition / Version:
- online
- Volume:
- online
- Issue:
- online
- ISSN:
- 0020-1812
- Page Range / eLocation ID:
- online
- Subject(s) / Keyword(s):
- Dispersal limitation Gulf Coastal Plain ‘Lost Pines’ of Central Texas mtDNA Population contraction Texas
- Format(s):
- Medium: X Size: online Other: online
- Size(s):
- online
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/s00040-024-00981-4
