Sexual and ontogenetic morphometric variation in Xiphopenaeus kroyeri (Crustacea, Decapoda, Penaeidae): a new approach with linear and angular morphometric data

The present study evaluates the ontogenetic/sexual morphometric variation in Xiphopenaeus kroyeri. Sampling was from July 2001 to June 2003 at Ubatuba, SAo Paulo, Brazil. Animals were sexed and measured (cephalothorax length-CC, partial of the rostral spine-CPR, rostral spine-CR and rostral spine an...

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Detalles Bibliográficos
Autores: Moraes, S. A. S. N., Alencar, C. E. R. D., Fransozo, A. [UNESP], Costa, R. C. [UNESP], Castilho, A. L. [UNESP], Freire, F. A. M.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2018
País:Brasil
Institución:Universidade Estadual Paulista (UNESP)
Repositorio:Repositório Institucional da UNESP
Idioma:inglés
OAI Identifier:oai:repositorio.unesp.br:11449/164622
Acceso en línea:http://dx.doi.org/10.1080/07924259.2018.1461691
http://hdl.handle.net/11449/164622
Access Level:acceso abierto
Palabra clave:Multivariate morphometry
Atlantic seabob
von Mises distribution
rostral spine angulation
Descripción
Sumario:The present study evaluates the ontogenetic/sexual morphometric variation in Xiphopenaeus kroyeri. Sampling was from July 2001 to June 2003 at Ubatuba, SAo Paulo, Brazil. Animals were sexed and measured (cephalothorax length-CC, partial of the rostral spine-CPR, rostral spine-CR and rostral spine angulation-AR). Data analysis included linear morphometric analysis: equation ln y = ln a + ln b (sex/ontogeny fitting), k-means method (ontogenetic classification), analysis of covariance (morphological maturity), removal of the allometric effect, verification of parametricity and collinearity, principal component (PCA) and linear discriminant analysis (visualization of tendencies), permutational multivariate analysis of variance (hypothesis test). In addition, circular analysis was undertaken: circular normal distribution and concentration parameter, circular analysis of variance (hypothesis test), PCA (observe tendencies) and linear-circular regression (ontogenetic trajectory, RA-dependent variable, CL-independent variable). Morphological changes in the cephalothorax, in the adult stage, may be related to the increase in size of the gonads during sexual maturation and to the development of gills during the transition from arthrobranch (juvenile) to dendrobranch (adult). The rostral spine, in the adult stage, tends to become more elongated and more sharply angled. This feature may be related to predation pressure on larger specimens (adults), knowing that throughout its ontogeny the rostral spine of this species assumes phenotypic traits that make swallowing more difficult for predators.