Genetic diversity in the Gammarus pecos species complex: Implications for conservation and regional biogeography in the Chihuahuan Desert

@article{Gervasio12004GeneticDI,
  title={Genetic diversity in the Gammarus pecos species complex: Implications for conservation and regional biogeography in the Chihuahuan Desert},
  author={Vivianaluxa Gervasio1 and David J. Berg2 and Brian K. Lang and Nathan L. Allan and Sheldon I. Guttman},
  journal={Limnology and Oceanography},
  year={2004},
  volume={49}
}
We used allozyme electrophoresis to quantify genetic variation in nine populations of the Gammarus pecos species complex endemic to spring systems of the northern Chihuahuan Desert. There was significant within‐population and high among‐population genetic variation. Two populations exhibited heterozygote deficiencies and high proportions of polymorphic loci, which suggests the presence of cryptic species. Genetic distances among populations were negatively correlated with previously published… 

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Disentangling the impact of demographic factors on population differentiation of an endangered freshwater crayfish (Austropotamobius pallipes) using population density and microsatellite data

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Critically low levels of genetic diversity in fragmented populations of the endangered Glenelg spiny freshwater crayfish Euastacus bispinosus

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Addressing the Linnean shortfall in a cryptic species complex

The general lineage concept of species is applied to an amphipod species complex that occupies springs of the northern Chihuahuan Desert, showing that each spring contains a genetically distinct population that is geographically isolated from other springs, suggesting evolutionary independence and status as separate species.

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Overall, cryptic diversity in amphipods strongly influenced apparent infection levels and parasite-induced mortality, and results from previous studies may also need to be reassessed in light of cryptic diversity and its pervasive effects.

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