INVESTIGADORES
IRIBARNE Oscar Osvaldo
artículos
Título:
Population structure of the SW Atlantic estuarine crab Neohelice granulata throughout its range: A genetic and morphometric study
Autor/es:
ITUARTE, R; A. DANATRO; T.A. LUPPI; P. RIBEIRO; SPIVAK, E; O. IRIBARNE,; E. LESSA
Revista:
ESTUARIES AND COASTS
Editorial:
SPRINGER
Referencias:
Lugar: Berlin; Año: 2012 vol. 35 p. 1249 - 1260
ISSN:
1559-2723
Resumen:
Abstract Phylogeographic patterns of the SW Atlantic estuarine
crab Neohelice granulata were examined using mitochondrial
DNA cytochrome oxidase I sequences and
analyzed together with morphometric data. Specimens were
sampled during a 4-year period (2001?2004) from 11 localities
encompassing the full distributional range of this species
along the SW Atlantic (22°57′ S to 42°25′ S). DNA
sequences were obtained from 69 individuals belonging to
seven localities, and morphometric variation in 12 continuous
characters was analyzed for 646 crabs from ten localities.
Strong genetic differentiation, consistent with a pattern
of isolation-by-distance, was detected among all localities
indicating that gene flow occurs mainly between neighboring
populations. Analyses of molecular variance showed
genetic subdivision between the southern (Argentina) and
the northern (Brazil) sites, suggesting restricted gene flow at
a regional scale. The genetic structure of this species could
be divided into two distinct groups due to a limited gene
flow between southern and northern regions as a consequence
of larval dispersal patterns. Coastal currents in the
vicinity of the Rio de la Plata likely act as a barrier to
dispersal within the species range. Moreover, genetic data
indicate that populations of N. granulata might have undergone
a northward demographic expansion since the late
Pleistocene. The morphometric analysis showed no geographical
pattern of morphological differentiation, although
there were differences among sampling sites.