Genetic characterization of captive Cuban crocodiles (Crocodylus rhombifer) and evidence of hybridization with the American crocodile (Crocodylus acutus)

• Published in: Journal of experimental zoology. Part A, Ecological genetics and physiology Vol. 309A; no. 10; pp. 649 - 660
• Main Authors: Weaver, Jeremy P., Rodriguez, David, Venegas-Anaya, Miryam, Cedeño-Vázquez, José Rogelio, Forstner, Michael R.J., Densmore III, Llewellyn D.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.12.2008
• Subjects: Alligators and Crocodiles - classification; Alligators and Crocodiles - genetics; Animals; Animals, Zoo - classification; Animals, Zoo - genetics; Crocodylus acutus; Crocodylus rhombifer; Cuba; Cytochromes b - genetics; Gene Frequency; Hybridization, Genetic - genetics; Microsatellite Repeats - genetics; Phylogeny; Cuba
• ISSN: 1932-5223; 1932-5231
• DOI: 10.1002/jez.471

There is a surprising lack of genetic data for the Cuban crocodile (Crocodylus rhombifer), especially given its status as a critically endangered species. Samples from captive individuals were used to genetically characterize this species in comparison with other New World crocodilians. Partial mitochondrial sequence data were generated from cyt‐b (843 bp) and the tRNAPro‐ tRNAPhe‐D‐loop region (442 bp). Phylogenetic analyses were performed by generating maximum parsimony, maximum likelihood, and Bayesian‐based topologies. In addition, in an effort to identify species‐specific alleles, ten polymorphic microsatellite loci were genotyped. Distance and model‐based clustering analyses were performed on microsatellite data, in addition to a model‐based assignment of hybrid types. Both mitochondrial and nuclear markers identified two distinct C. rhombifer genetic sub‐clades (α and β); and microsatellite analyses revealed that most admixed individuals were F2 hybrids between C. rhombifer‐α and the American crocodile (C. acutus). All individuals in the C. rhombifer‐β group were morphologically identified as C. acutus and formed a distinct genetic assemblage. J. Exp. Zool. 309A:649–660, 2008. © 2008 Wiley‐Liss, Inc.