黄颡鱼的两性异形和雌性繁殖特征

Sexual Dimorphism and Female Reproductive Characteristics of Pseudobagrus fulvidraco

测定了黄颡鱼成体的体长、头长、头宽、头高、吻长、眼径、眼间距、眼后头长、体高、尾柄高、背鳍基前距、背鳍基长、尾柄长、腹鳍基前距、背鳍脂鳍间距、腹鳍臀鳍间距、尾鳍长、体重、去内脏体重等形态指标以及雌体的怀卵数量。雌性成体的体长显著小于雄性成体。其它局部特征皆与体长呈正相关,回归剩余值的t检验表明,雌性成体的眼径、头高、体高、腹鳍基前距、体重显著大于雄性成体,其它局部形态特征不存在显著的两性差异。黄颡鱼雌体通过个体大小的增加和腹部形态的改变增加腹腔容量,增加繁殖输出。

We measured some morphological traits, including the body length, head length, head width, head depth, snout length, eye diameter, interorbital width, postorbital head length, body depth, caudal peduncle depth, dorsal fin precoxal length, dorsal fin coxal length, caudal peduncle length, pelvic fin precoxal length, the space between dorsal fin and adipose fin, the space between pelvic fin and anal fin, caudal fin length, body weight, carcass weight, and individual fecundity in a population of Pseudobagrus fulvidraco, from Oujiang River, Lishui City, Zhejiang Province. Our results showed that the body length of adult females was significantly shorter than that of adult males. All other morphological traits were positively correlated with the body length. The t test of residuals indicated that adult females were significantly larger than adult males in eye diameter, head width, body depth, pelvic fin precoxal length and body weight, while there existed no apparent sex difference among other morphological traits. The analysis indicates that adult females of P.fulvidraco increase their the capacity of abdominal cavity and the breeding output through individual size increase and the morphological changes of abdomen.