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17. High levels of population genetic differentiation in the American crocodile (Crocodylus acutus)

Author

American Museum of Natural History, Wildlife Conservation Society, Columbia University, Rossi, Natalia A., Menchaca-Rodríguez, Angelica, Antelo, Rafael, Wilson, Bryon, McLaren, K., Mazotti, Frank, Crespo, Rafael, Wasilewski, Joe, Alda, Fernando, Doadrio, Ignacio, Barros, Tito R., Hekkala, Evon, Alonso-Tabet, Manuel, Alonso-Giménez, Yairen, López, Manuel, Espinosa-Lopez, Georgina, Burgess, Joe, Thorbjarnarson, John B., Ginsberg, Joshua R., Vliet, Kent A., Amato, George, American Museum of Natural History, Wildlife Conservation Society, Columbia University, Rossi, Natalia A., Menchaca-Rodríguez, Angelica, Antelo, Rafael, Wilson, Bryon, McLaren, K., Mazotti, Frank, Crespo, Rafael, Wasilewski, Joe, Alda, Fernando, Doadrio, Ignacio, Barros, Tito R., Hekkala, Evon, Alonso-Tabet, Manuel, Alonso-Giménez, Yairen, López, Manuel, Espinosa-Lopez, Georgina, Burgess, Joe, Thorbjarnarson, John B., Ginsberg, Joshua R., Vliet, Kent A., and Amato, George

Abstract

The American crocodile (Crocodylus acutus) is a widely distributed species across coastal and brackish areas of the Neotropical region of the Americas and the Greater Antilles. Available information on patterns of genetic differentiation in C. acutus shows a complex structuring influenced by interspecific interactions (mainly hybridization) and anthropogenic actions (mostly historical hunting, recent poaching, habitat loss and fragmentation, and unintentional translocation of individuals). In this study, we used data on mitochondrial DNA control region and 11 nuclear polymorphic microsatellite loci to assess the degree of population structure of C. acutus in South America, North America, Central America and the Greater Antilles. We used traditional genetic differentiation indices, Bayesian clustering and multivariate methods to create a more comprehensive picture of the genetic relationships within the species across its range. Analyses of mtDNA and microsatellite loci show evidence of a strong population genetic structure in the American crocodile, with unique populations in each sampling locality. Our results support previous findings showing large degrees of genetic differentiation between the continental and the Greater Antillean C. acutus. We report three new haplotypes unique to Venezuela, which are considerably less distant from the Central and North American haplotypes than to the Greater Antillean ones. Our findings reveal genetic population differentiation between Cuban and Jamaican C. acutus and offer the first evidence of strong genetic differentiation among the populations of Greater Antillean C. acutus.

Published
2020

18. High levels of population genetic differentiation in the American crocodile (Crocodylus acutus)

Author

Rossi, Natalia A., primary, Menchaca-Rodriguez, Angelica, additional, Antelo, Rafael, additional, Wilson, Byron, additional, McLaren, Kurt, additional, Mazzotti, Frank, additional, Crespo, Rafael, additional, Wasilewski, Joe, additional, Alda, Fernando, additional, Doadrio, Ignacio, additional, Barros, Tito R., additional, Hekkala, Evon, additional, Alonso-Tabet, Manuel, additional, Alonso-Giménez, Yairen, additional, Lopez, Manuel, additional, Espinosa-Lopez, Georgina, additional, Burgess, Joe, additional, Thorbjarnarson, John B., additional, Ginsberg, Joshua R., additional, Vliet, Kent A., additional, and Amato, George, additional

Published
2020
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21. High levels of population genetic differentiation in the American crocodile (Crocodylus acutus)

Author

Rossi, Natalia Alejandra, primary, Menchaca-Rodriguez, Angelica, additional, Antelo, Rafael, additional, Wilson, Byron, additional, McLaren, Kurt, additional, Mazzotti, Frank, additional, Crespo, Rafael, additional, Wasilewski, Joe, additional, Alda, Fernando, additional, Doadrio, Ignacio, additional, Barros, Tito R, additional, Hekkala, Evon, additional, Alonso-Tabet, Manuel, additional, Alonso-Giménez, Yairen, additional, Lopez, Manuel, additional, Espinosa-Lopez, Georgina, additional, Burgess, Joe, additional, Thorbjarnarson, John B., additional, Ginsberg, Joshua R., additional, Vliet, Kent A., additional, and Amato, George, additional

Published
2019
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25. Tropical cyclones and reproductive ecology of Crocodylus acutus Cuvier, 1807 (Reptilia: Crocodilia: Crocodylidae) on a Caribbean atoll in Mexico

Author

Charruau, Pierre, Thorbjarnarson, John B., and Hénaut, Yann

Subjects
Biodiversity, Taxonomy
Abstract

Charruau, Pierre, Thorbjarnarson, John B., Hénaut, Yann (2010): Tropical cyclones and reproductive ecology of Crocodylus acutus Cuvier, 1807 (Reptilia: Crocodilia: Crocodylidae) on a Caribbean atoll in Mexico. Journal of Natural History 44 (11-12): 741-761, DOI: 10.1080/00222930903490993, URL: http://dx.doi.org/10.1080/00222930903490993

Published
2010

32. ORINOCO CROCODILE CROCODYLUS INTERMEDIUS

Author

Seijas, Andrés E., Antelo, Rafael, Thorbjarnarson, John B., and Ardila Robayo, María Cristina

Subjects
57 Ciencias de la vida, Biología / Life sciences, biology, 59 Animales / Animals, Caimán del Orinoco,Venezuela, Colombia, 55 Ciencias de la tierra / Earth sciences and geology
Abstract

The Orinoco crocodile is a large, relatively long-nosed crocodile restricted to the middle and lower reaches of the Orinoco River and its tributaries in Venezuela and Colombia Although this crocodile was found in a wide variety of habitats, including rivers in tropical evergreen forest and piedmont streams in the foothills of the Andes, it reached its greatest numbers in the seasonal rivers of the Llanos savanna region

Published
1992

40. Size estimation, morphometrics, sex ratio, sexual size dimorphism, and biomass of Crocodylus acutus in the coastal zone of Belize.

Author

PLATT, STEVEN G., RAINWATER, THOMAS R., THORBJARNARSON, JOHN B., and MARTIN, DAVID

Abstract

The article presents a study which determines the sexual size dimorphism, size population, morphometrics, sex ratio, and biomass of Crocodylus (C.) acutus in the coastal zone of Belize. It mentions that the measurements obtained from the crocodiles captured during 1996-1998, 2002, and 2008-2009 include total length, snout-vent length (SVL), and dorsal cranial length (DCL). It notes that the sexual size dimorphism index (SDI) for C. acutus was 2.10. It adds that the C. acutus in coastal Belize seem to have a smaller body size than those reported populations.

Published
2011

41. Hybridization between Crocodylus acutus and Crocodylus moreletii in the Yucatan Peninsula: I. evidence from mitochondrial DNA and morphology

Author

CedeñoVázquez, José Rogelio, Rodriguez, David, Calmé, Sophie, Ross, James Perran, Densmore, Llewellyn D., and Thorbjarnarson, John B.

Abstract

The American crocodile Crocodylus acutus and the Morelets crocodile C. moreletii are broadly sympatric in Belize and Mexico. The presence of morphologically anomalous individuals in the overlapping range area suggests possible hybridization between these species. Analysis of 477 base pairs of the mitochondrial tRNAProtRNAPheDloop region revealed the presence of pure C. acutusN43 and C. moreletiiN56, as well as a high proportion of interspecific hybrids N17, 14.6 in the Yucatan Peninsula, Mexico. Although all individuals could be assigned to one species or other based on phenotypic characters, some had been characterized as potential hybrids in the field by anomalous scale counts. The hybridization zone lies along the area of sympatry between C. acutusand C. moreletiiinvestigated in this study, but extends further inland if hybrid localities from Belize are included. Hybridization in the Yucatan Peninsula is bidirectional, which indicates considerably more genetic contact between these species than previously recognized, and is probably more detrimental to the genetic integrity of smaller C. acutuspopulations. A more intensive study of the pattern of hybridization is warranted and supports continued classification of C. acutusas a critically threatened species in the Yucatan Peninsula. J. Exp. Zool. 309A:661–673, 2008. © 2008 WileyLiss, Inc.

Published
2008
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44. Hybridization between Crocodylus acutus and Crocodylus moreletii in the Yucatan Peninsula: I. Evidence from mitochondrial DNA and morphology.

Author

Cedeño-Vázquez JR, Rodriguez D, Calmé S, Ross JP, Densmore LD, and Thorbjarnarson JB

Subjects
Alligators and Crocodiles classification, Animals, Female, Haplotypes, Male, Mexico, Molecular Sequence Data, Phylogeny, Alligators and Crocodiles anatomy & histology, Alligators and Crocodiles genetics, DNA, Mitochondrial genetics, Hybridization, Genetic genetics
Abstract

The American crocodile (Crocodylus acutus) and the Morelet's crocodile (C. moreletii) are broadly sympatric in Belize and Mexico. The presence of morphologically anomalous individuals in the overlapping range area suggests possible hybridization between these species. Analysis of 477 base pairs of the mitochondrial tRNA(Pro)-tRNA(Phe)-Dloop region revealed the presence of pure C. acutus (N=43) and C. moreletii (N=56), as well as a high proportion of interspecific hybrids (N=17, 14.6%) in the Yucatan Peninsula, Mexico. Although all individuals could be assigned to one species or other based on phenotypic characters, some had been characterized as potential hybrids in the field by anomalous scale counts. The hybridization zone lies along the area of sympatry between C. acutus and C. moreletii investigated in this study, but extends further inland if hybrid localities from Belize are included. Hybridization in the Yucatan Peninsula is bidirectional, which indicates considerably more genetic contact between these species than previously recognized, and is probably more detrimental to the genetic integrity of smaller C. acutus populations. A more intensive study of the pattern of hybridization is warranted and supports continued classification of C. acutus as a critically threatened species in the Yucatan Peninsula., ((c) 2008 Wiley-Liss, Inc.)

Published
2008
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