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

Abstract

Grupo de estudos em ecologia e Fisiologia de animais aquáticos, universidade Federal do rio Grande do norte, natal, brasil; b núcleo de estudos em biologia, ecologia e cultura de crustáceos, universidade estadual paulista, bauru, brasil; c laboratório de biologia de camarões marinhos e de Água doce, universidade estadual paulista, bauru, brasil;

Geometric morphometric analysis of the variations in cephalothorax shape of the freshwater prawn Macrobrachium tenellum, Smith (Decapoda Palaemonidae) from two different coastal basins in Oaxaca, Mexico

“…5b; Table 3). The absence of sexual dimorphism was also found by Moraes et al (2018) in Xiphopenaeus kroyeri specimens.…”

“…Previous research has stated that body length is associated with environmental factors such as a biomechanical response to locomotion needs, which depends on water flow and feeding behavior (Zimmermann et al 2012, Mazancourt et al 2017. Moraes et al (2018) evaluated the variation of the cephalothorax and rostrum at different developmental stages, focusing on the correlation patterns between shape and size and phenotypic covariation between both structures. Geometric morphometric techniques with Decapoda are applied mostly on marine shrimps (Tzeng et al 2001, 2004, Anastasiadou & Leonardos 2008, Anastasiadou et al 2009, Konan et al 2010.…”

Biometric relationships and sex ratio for red-spotted shrimp Farfantepenaeus brasiliensis (Latreille, 1817) (Decapoda, Penaeidae) from the coast of Sergipe, northeastern Brazil

“…Regarding the RL vs CL relationship, May-Kú et al (2006) also reported a negative allometry for juveniles of F. brasiliensis off Mexico. However, studies carried out with X. kroyeri indicated differences in the RL vs CL relationship between juveniles and adults, with faster increase (positive allometry) being observed in juveniles (Moraes et al, 2018). Faster increase of the rostrum length during the juvenile stage could be a strategy of this species to avoid predation, as observed in X. kroyeri (Moraes et al, 2018) The weight-length relationships showed contrasting patterns.…”

“…However, studies carried out with X. kroyeri indicated differences in the RL vs CL relationship between juveniles and adults, with faster increase (positive allometry) being observed in juveniles (Moraes et al, 2018). Faster increase of the rostrum length during the juvenile stage could be a strategy of this species to avoid predation, as observed in X. kroyeri (Moraes et al, 2018) The weight-length relationships showed contrasting patterns. When the W W vs TL relationship was estimated, the allometry was positive for both sexes indicating a higher increase in weight than expected by the increase in total length.…”

Relative growth and morphological sexual maturity of the caridean prawn Macrobrachium villosimanus (Tiwari, 1949) (Decapoda: Palaemonidae)

“…Such studies provide a good method to elucidate the relationships between process of growth and evolution (Blackstone, 1987). Their type of growth also indicates a definite division of their ontogeny into distinct stages, revealing great differences between the growth rates of males and females, and of juveniles and adults (Hartnoll, 1978;Moraes et al, 2018). Some stages during the life cycle are very crucial for reproductive success, including the transition from the juvenile to the adult.…”