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Conservation Genetics

, Volume 5, Issue 4, pp 449–462 | Cite as

Low Levels of Nucleotide Diversity in Crocodylus moreletii and Evidence of Hybridization with C. acutus

  • David A. Ray
  • Jennifer A. Dever
  • Steven G. Platt
  • Thomas R. Rainwater
  • Adam G. Finger
  • Scott T. McMurry
  • Mark A. Batzer
  • Brady Barr
  • Peter J. Stafford
  • Jenna McKnight
  • Llewellyn D. Densmore
Article

Abstract

Examinations of both population genetic structure and the processes that lead to such structure in crocodilians have been initiated in several species in response to a call by the IUCN Crocodile Specialist Group. A recent study used microsatellite markers to characterize Morelet's crocodile (Crocodylus moreletii) populations in north-central Belize and presented evidence for isolation by distance. To further investigate this hypothesis, we sequenced a portion of the mitochondrial control region for representative animals after including samples from additional locales in Belize, Guatemala and Mexico. While there is limited evidence of subdivision involving other locales, we found that most of the differentiation among populations of C. moreletiican be attributed to animals collected from a single locale in Belize, Banana Bank Lagoon. Furthermore, mitochondrial DNA sequence analysis showed that animals from this and certain other locales display a haplotype characteristic of the American crocodile, C. acutus, rather than C. moreletii. We interpret this as evidence of hybridization between the two species and comment on how these new data have influenced our interpretation of previous findings. We also find very low levels of nucleotide diversity in C. moreletiihaplotypes and provide evidence for a low rate of substitution in the crocodilian mitochondrial control region. Finally, the conservation implications of these findings are discussed.

Crocodylus D-loop hybridization mtDNA phylogeography 

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Copyright information

© Kluwer Academic Publishers 2004

Authors and Affiliations

  • David A. Ray
    • 1
    • 2
  • Jennifer A. Dever
    • 3
  • Steven G. Platt
    • 4
    • 4
  • Thomas R. Rainwater
    • 5
  • Adam G. Finger
    • 1
  • Scott T. McMurry
    • 1
  • Mark A. Batzer
    • 2
  • Brady Barr
    • 6
  • Peter J. Stafford
    • 7
  • Jenna McKnight
    • 8
  • Llewellyn D. Densmore
    • 1
  1. 1.Department of Biological Sciences, MS 3131Texas Tech UniversityLubbockUSA
  2. 2.Department of Biological SciencesLouisiana State UniversityBaton RougeUSA
  3. 3.University of San FranciscoHarney Science CenterSan FranciscoUSA
  4. 4.Wildlife Conservation SocietyBronxUS
  5. 5.The Institute of Environmental and Human HealthTexas Tech UniversityLubbockUSA
  6. 6.National Geographic SocietyWashingtonUSA
  7. 7.The Natural History MuseumLondonUK
  8. 8.Department of BiologyUniversity of MiamiCoral GablesUSA

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