Morphology and size variation of a portunoid crab from the Maastrichtian of the Americas
Por:
Vega F.J., Phillips G.E., Nyborg T., Flores-Ventura J., Clements D., Espinosa B., Solís-Pichardo G.
Publicada:
1 nov 2013
Resumen:
The portunoid crab Ophthalmoplax Rathbun, 1935, is known from late
Cretaceous deposits of Africa and the Americas. A review of 76 specimens
from many localities in North and South America reveals that the genus
is represented by only two species - one in Africa (recently described)
and the other in the Americas. Ophthalmoplax brasiliana (Maury, 1930)
was distributed along the Atlantic and Gulf coasts of the Americas
throughout the Maastrichtian - from Brazil to North Carolina. In early
Maastrichtian deposits of North America (similar to 69.0 Ma), the
species is represented by local populations of medium-sized individuals,
and by the late Maastrichtian (similar to 67.0 Ma), populations of
larger individuals became abundant. This size increase may be related to
a decrease in ocean water temperatures. Populations of medium-sized
individuals are found again in the latest Maastrichtian (similar to 66.2
Ma), below strata with ejecta deposits in Coahuila, Mexico, and in the
uppermost Owl Creek Formation, Mississippi. This size decrease is
possibly linked to an increase in seawater temperature occurring just
below the K/P boundary, when Ophthalmoplax became extinct. (C) 2013
Elsevier Ltd. All rights reserved.
Filiaciones:
Vega F.J.:
Univ Nacl Autonoma Mexico, Inst Geol, Mexico City 04510, DF, Mexico
Phillips G.E.:
Conservation Biology Section, Mississippi Museum of Natural Science, 2148 Riverside Drive, Jackson, MI 39202-1353, United States
Nyborg T.:
Department of Earth and Biological Sciences, Loma Linda University, Loma Linda, CA 92350, United States
Flores-Ventura J.:
not available, Santa Engracia 257, Fraccionamiento Santa Elena, 25015 Saltillo, Coahuila, Mexico
Clements D.:
not available, 67 South Hummingbird Lane, Rocky Point, NC 28457, United States
Espinosa B.:
Benemérita Escuela Normal de Coahuila, Calzada de los Maestros s/n, Zona Centro, Saltillo, Coahuila 25000, Mexico
Solís-Pichardo G.:
Univ Nacl Autonoma Mexico, Inst Geol, Mexico City 04510, DF, Mexico
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