Relaciones morfométricas en machos de cangrejo azul (Cardisoma crassum) y su relación con la madurez sexual
Fecha
2019
Autores
Título de la revista
ISSN de la revista
Título del volumen
Editor
Facultad de Ciencias Naturales. Universidad de Guayaquil
Resumen
En la costa continental norte de Ecuador se recolectaron 490 individuos machos de cangrejo azul (Cardisoma crassum), con el objetivo de establecer características morfométricas y su relación con la madurez sexual. Cada individuo fue medido considerando el ancho, largo y alto del cefalotórax, así como, de las quelas derechas e izquierda. Los rangos de tallas observados estuvieron entre 55.26 y 105.28 mm AnC, 38.79 y 77.90 mm LC, 48.46 y 24.74 mm AlC. La quela derecha tuvo mayor tamaño en el 52% de los individuos, la izquierda en el 42% mientras que, el 6% de los cangrejos fueron homoquelos. Se encontraron diferencias significativas (p < 0.01) entre las dimensiones morfométricas de la quela derecha e izquierda, así como, entre la quela mayor y menor. Mediante regresiones lineales se observó que, las relaciones entre las variables morfométricas tuvieron una tendencia lineal con un alto coeficiente de correlación (r ≥ 0.80). Los valores de las pendientes (b) mostraron un crecimiento alométrico negativo (b < 1) en la mayoría de las regresiones, excepto para AlQM vs AnC (b = 1.29) y AnQM vs LC (b = 1.62) que fueron positivas. Dos grupos de datos fueron identificados en las relaciones entre alto y largo de la quela vs el ancho y largo del cefalotórax, lo cual posiblemente se encuentra asociado con la presencia de individuos juveniles y adultos. El punto de separación entre fases de desarrollo ontogénico no pudo ser detectado por la ausencia de individuos de tallas pequeñas (< 55 mm AnC).
On the mainland coast of Ecuador, 490 males of blue crab (Cardisoma crassum) were collected, with the aim of establishing morphometric characteristics and their relationship with sexual maturity. The individuals were measured considering the width, length and height of the carapace, as well as the right and left chelaes. The observed size ranges were 55.26-105.28 mm CW, 38.79-77.90 mm CL, 48.46-24.74 mm CH. The right chelae had greater size in 52% of the individuals, the left one in 42% while, the 6% of the crabs were homochelos. Significant differences were found (p < 0.01) between the morphometric dimensions of the right and left chelae, as well as between the major and minor chela. Using linear regressions, it was observed that the relationships between the morphometric variables had a linear tendency with a high correlation coefficient (r ≥ 0.80). The values of the slopes (b) showed a negative allometric growth (b < 1) in most of the regressions, except for AlQM vs AnC (b = 1.29) and AnQM vs LC (b = 1.62) that were positive. Two groups of data were identified in the relationships between height and length of the chela vs the width and length of the carapace, which is possibly associated with the presence of juvenile and adult individuals. The point of separation between phases of ontogenetic development could not be detected by the absence of individuals of small sizes (< 55 mm CW).
On the mainland coast of Ecuador, 490 males of blue crab (Cardisoma crassum) were collected, with the aim of establishing morphometric characteristics and their relationship with sexual maturity. The individuals were measured considering the width, length and height of the carapace, as well as the right and left chelaes. The observed size ranges were 55.26-105.28 mm CW, 38.79-77.90 mm CL, 48.46-24.74 mm CH. The right chelae had greater size in 52% of the individuals, the left one in 42% while, the 6% of the crabs were homochelos. Significant differences were found (p < 0.01) between the morphometric dimensions of the right and left chelae, as well as between the major and minor chela. Using linear regressions, it was observed that the relationships between the morphometric variables had a linear tendency with a high correlation coefficient (r ≥ 0.80). The values of the slopes (b) showed a negative allometric growth (b < 1) in most of the regressions, except for AlQM vs AnC (b = 1.29) and AnQM vs LC (b = 1.62) that were positive. Two groups of data were identified in the relationships between height and length of the chela vs the width and length of the carapace, which is possibly associated with the presence of juvenile and adult individuals. The point of separation between phases of ontogenetic development could not be detected by the absence of individuals of small sizes (< 55 mm CW).
Descripción
Palabras clave
ALOMETRÍA, CRECIMIENTO RELATIVO, MADUREZ SEXUAL, MORFOMETRÍA