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Phylogenetic and morphologic analyses of a coastal fish reveals a marine biogeographic break of terrestrial origin in the southern Caribbean.

Betancur-R R, Acero P A, Duque-Caro H, Santos SR - PLoS ONE (2010)

Bottom Line: The estimated approximately 0.86 my divergence of the lineages from a common ancestor coincides with the timing of the SMM displacement at approximately 0.78 my.Results presented here support the hypothesis that organismal properties as well as extrinsic factors lead to diversification of the Cathorops mapale group along the northern coast of South America.Comparative examination of additional Southern Caribbean taxa, particularly those with varying life history traits and dispersal capabilities, will determine the extent by which the SMM has influenced marine phylogeography in the region.

View Article: PubMed Central - PubMed

Affiliation: Department of Biological Sciences, Auburn University, Auburn, Alabama, USA. betanri@gmail.com

ABSTRACT

Background: Marine allopatric speciation involves interplay between intrinsic organismal properties and extrinsic factors. However, the relative contribution of each depends on the taxon under study and its geographic context. Utilizing sea catfishes in the Cathorops mapale species group, this study tests the hypothesis that both reproductive strategies conferring limited dispersal opportunities and an apparent geomorphologic barrier in the Southern Caribbean have promoted speciation in this group from a little studied area of the world.

Methodology/principal findings: Mitochondrial gene sequences were obtained from representatives of the Cathorops mapale species group across its distributional range from Colombia to Venezuela. Morphometric and meristic analyses were also done to assess morphologic variation. Along a approximately 2000 km transect, two major lineages, Cathorops sp. and C. mapale, were identified by levels of genetic differentiation, phylogenetic reconstructions, and morphological analyses. The lineages are separated by approximately 150 km at the Santa Marta Massif (SMM) in Colombia. The northward displacement of the SMM into the Caribbean in the early Pleistocene altered the geomorphology of the continental margin, ultimately disrupting the natural habitat of C. mapale. The estimated approximately 0.86 my divergence of the lineages from a common ancestor coincides with the timing of the SMM displacement at approximately 0.78 my.

Main conclusions/significance: Results presented here support the hypothesis that organismal properties as well as extrinsic factors lead to diversification of the Cathorops mapale group along the northern coast of South America. While a lack of pelagic larval stages and ecological specialization are forces impacting this process, the identification of the SMM as contributing to allopatric speciation in marine organisms adds to the list of recognized barriers in the Caribbean. Comparative examination of additional Southern Caribbean taxa, particularly those with varying life history traits and dispersal capabilities, will determine the extent by which the SMM has influenced marine phylogeography in the region.

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Sampling localities for the Cathorops mapale group along the southern Caribbean.Arrow indicates Parque Nacional Natural Tayrona (PNNT), where the continental shelf is narrower (gray line shows 200 m isobath). UR, Urabá; GM*, Golfo de Morrosquillo; CT, Cartagena; CG, Ciénaga Grande de Santa Marta; GS, Golfo de Salamanca; CM, Camarones; RH, Riohacha; BP*, Bahía Portete; PC, Puerto Cabello; IM, Isla Margarita; CA, Carupano; GP, Golfo de Paria (map from www.aquarius.ifm-geomar.de). *Only morphological material examined from these localities.
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pone-0011566-g001: Sampling localities for the Cathorops mapale group along the southern Caribbean.Arrow indicates Parque Nacional Natural Tayrona (PNNT), where the continental shelf is narrower (gray line shows 200 m isobath). UR, Urabá; GM*, Golfo de Morrosquillo; CT, Cartagena; CG, Ciénaga Grande de Santa Marta; GS, Golfo de Salamanca; CM, Camarones; RH, Riohacha; BP*, Bahía Portete; PC, Puerto Cabello; IM, Isla Margarita; CA, Carupano; GP, Golfo de Paria (map from www.aquarius.ifm-geomar.de). *Only morphological material examined from these localities.

Mentions: Taxonomic sampling within the genus Cathorops was designed following the phylogenetic hypotheses of Betancur-R. et al. [20] and Betancur-R [27]. In addition to the C. mapale group (C. mapale and Cathorops sp.), the ingroup included the closely related C. fuerthii group (C. fuerthii, C. aff. fuerthii, and C. manglarensis; from the Eastern Pacific) and C. cf. higuchii (from Nicaraguan Caribbean). We used C. spixii, C. agassizii, and C. hypophthalmus as outgroups. Sample size within the C. mapale group consisted of 17 individuals from each lineage collected at 10 locations along its distributional range, with a focus on neighboring localities from either side of the Parque Nacional Natural Tayrona (PNNT) in Santa Marta, Colombia (Fig. 1; Table S1), which represents the distributional breakpoint between the lineages (see below). This sample size represents individuals collected during multiple field trips to Venezuela and Colombia from 2003 to 2008 by RBR and AAP. Institutional abbreviations are as listed at ASIH website (2010) http://www.asih.org/codons.pdf, with the addition of stri-x: tissue collection, Smithsonian Tropical Research Institute. SL is standard length. Two letter country codes follow ISO-3166.


Phylogenetic and morphologic analyses of a coastal fish reveals a marine biogeographic break of terrestrial origin in the southern Caribbean.

Betancur-R R, Acero P A, Duque-Caro H, Santos SR - PLoS ONE (2010)

Sampling localities for the Cathorops mapale group along the southern Caribbean.Arrow indicates Parque Nacional Natural Tayrona (PNNT), where the continental shelf is narrower (gray line shows 200 m isobath). UR, Urabá; GM*, Golfo de Morrosquillo; CT, Cartagena; CG, Ciénaga Grande de Santa Marta; GS, Golfo de Salamanca; CM, Camarones; RH, Riohacha; BP*, Bahía Portete; PC, Puerto Cabello; IM, Isla Margarita; CA, Carupano; GP, Golfo de Paria (map from www.aquarius.ifm-geomar.de). *Only morphological material examined from these localities.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2903491&req=5

pone-0011566-g001: Sampling localities for the Cathorops mapale group along the southern Caribbean.Arrow indicates Parque Nacional Natural Tayrona (PNNT), where the continental shelf is narrower (gray line shows 200 m isobath). UR, Urabá; GM*, Golfo de Morrosquillo; CT, Cartagena; CG, Ciénaga Grande de Santa Marta; GS, Golfo de Salamanca; CM, Camarones; RH, Riohacha; BP*, Bahía Portete; PC, Puerto Cabello; IM, Isla Margarita; CA, Carupano; GP, Golfo de Paria (map from www.aquarius.ifm-geomar.de). *Only morphological material examined from these localities.
Mentions: Taxonomic sampling within the genus Cathorops was designed following the phylogenetic hypotheses of Betancur-R. et al. [20] and Betancur-R [27]. In addition to the C. mapale group (C. mapale and Cathorops sp.), the ingroup included the closely related C. fuerthii group (C. fuerthii, C. aff. fuerthii, and C. manglarensis; from the Eastern Pacific) and C. cf. higuchii (from Nicaraguan Caribbean). We used C. spixii, C. agassizii, and C. hypophthalmus as outgroups. Sample size within the C. mapale group consisted of 17 individuals from each lineage collected at 10 locations along its distributional range, with a focus on neighboring localities from either side of the Parque Nacional Natural Tayrona (PNNT) in Santa Marta, Colombia (Fig. 1; Table S1), which represents the distributional breakpoint between the lineages (see below). This sample size represents individuals collected during multiple field trips to Venezuela and Colombia from 2003 to 2008 by RBR and AAP. Institutional abbreviations are as listed at ASIH website (2010) http://www.asih.org/codons.pdf, with the addition of stri-x: tissue collection, Smithsonian Tropical Research Institute. SL is standard length. Two letter country codes follow ISO-3166.

Bottom Line: The estimated approximately 0.86 my divergence of the lineages from a common ancestor coincides with the timing of the SMM displacement at approximately 0.78 my.Results presented here support the hypothesis that organismal properties as well as extrinsic factors lead to diversification of the Cathorops mapale group along the northern coast of South America.Comparative examination of additional Southern Caribbean taxa, particularly those with varying life history traits and dispersal capabilities, will determine the extent by which the SMM has influenced marine phylogeography in the region.

View Article: PubMed Central - PubMed

Affiliation: Department of Biological Sciences, Auburn University, Auburn, Alabama, USA. betanri@gmail.com

ABSTRACT

Background: Marine allopatric speciation involves interplay between intrinsic organismal properties and extrinsic factors. However, the relative contribution of each depends on the taxon under study and its geographic context. Utilizing sea catfishes in the Cathorops mapale species group, this study tests the hypothesis that both reproductive strategies conferring limited dispersal opportunities and an apparent geomorphologic barrier in the Southern Caribbean have promoted speciation in this group from a little studied area of the world.

Methodology/principal findings: Mitochondrial gene sequences were obtained from representatives of the Cathorops mapale species group across its distributional range from Colombia to Venezuela. Morphometric and meristic analyses were also done to assess morphologic variation. Along a approximately 2000 km transect, two major lineages, Cathorops sp. and C. mapale, were identified by levels of genetic differentiation, phylogenetic reconstructions, and morphological analyses. The lineages are separated by approximately 150 km at the Santa Marta Massif (SMM) in Colombia. The northward displacement of the SMM into the Caribbean in the early Pleistocene altered the geomorphology of the continental margin, ultimately disrupting the natural habitat of C. mapale. The estimated approximately 0.86 my divergence of the lineages from a common ancestor coincides with the timing of the SMM displacement at approximately 0.78 my.

Main conclusions/significance: Results presented here support the hypothesis that organismal properties as well as extrinsic factors lead to diversification of the Cathorops mapale group along the northern coast of South America. While a lack of pelagic larval stages and ecological specialization are forces impacting this process, the identification of the SMM as contributing to allopatric speciation in marine organisms adds to the list of recognized barriers in the Caribbean. Comparative examination of additional Southern Caribbean taxa, particularly those with varying life history traits and dispersal capabilities, will determine the extent by which the SMM has influenced marine phylogeography in the region.

Show MeSH
Related in: MedlinePlus