The healthy male Paracanthobrama guichenoti were employed and the spermatozoa were collected from the body by artificial conduction. The sperm was observed under the scan electron microscope. Meanwhile

effects of temperature

salinity on sperm motility were studied. The results showed that: the sperm of Paracanthobrama guichenoti containing 3 parts

a head

a middlepiece and a long tail. The head is subcircle in shape. The main structure of the head is nucleus. There is no acrosome at the anterior end of the nucleus

whereas there is an implantation fossa at the posterior end of the nucleus

within which the chromatin is dense; The sleeve of the middlepiece

which is rich in mitochondria and vesicles

is connected to the posterior end of the nucleus; The tail part is slender

including principal piece and end piece. The main structure is axoneme

which is the structure of a typical “9+2”.The effects of water temperature on spermatozoa motility showed that the optimum water temperature is 24 ℃ when the spermatozoa have the longest life of span(1 900)，and the optimum range of water temperature is 20~28℃. When the salinity of water at 5‰~8‰，the spermatozoa have the best motility and the spermatozoa have the longest life span at salinity 7‰，which is 1 350 s.