Aspects of the populational structure of the "sagüiru” Curimata gilberti Quoy & Gaymard, 1824 [= Cyphocharax modesta Fernandez í Yepez, 1948] [Characiformes, Curimatidae], in ponte Nova Reservoir, Tietê River, São Paulo State, Brazil

Abstract

In this paper, 1976 specimens of "saguiru" Cyphocharax modesta Femandez-Yepez, 1948, caught in Ponte Nova Reservoir during the period of April 1976 to March 1978, were analyzed. The objective is to study aspects of population structure in distinct seasons of the year. It is observed in this period the predominance of females (55.57%); the females attain superior length in relation to males and are predominant in the largest length classes. It was also observed the mean length of first maturation (Lpm=13.65 cm) to females. After the total length of 14.75 cm, all the female specimens of this population are suitable to reproduction (L_100%). The relationships between body weight and total length, determined to males and to females, resulted in:  W = 0.0104 L^3.1062  and  W = 0.0108 L^3.1023.