方格星虫繁殖生物学研究-水产学报.PDF

26 6 Vol. 26, No . 6 2002 12 JOURNAL OF FISHERIES OF CHINA Dec. , 2002 : 1000- 0615( 2002) 06- 0503- 0 兰国宝, 阎 冰 ( , 536000) : , 3 , 1999 1 2000 2 , ; , ( 1~ 2m) ( 3~ 30m) ( 30~ 0m ) ( 0~ 160m) ( 160m) 5 ; 4 , , 4- 9 , 5- 8 : ; ; ; : Q954. 43 : A The reproductive biology of peanut worm, Sip unculus nudus LAN Guo-bao, YAN Bing ( Guangxi Institute of Oceanology , Beihai 536000, China) Abstract: The development of germ cells of peanut worms, Sip unculus nudus , proceeding with seasonal alternating was observed by optical microscope to study reproductive cycle of the population in the sea of Guangxi. Samples were collected monthly from January 1999 to February 2000 at three sites along the coastal sea from Daguansha to Baihutou in southern Beihai. Observations in this study have bring to light as follow: All individuals observed were dioecious. The earliest germ cells of both males and females were small in size and appeared in clumps attached to nurse cells of motive activity . The oocytes underwent five stages of development: cell multiplication ( 1- 2m in diameter) , plasmic growth ( 3- 30m) , follicle formation( 30- 0m ) , jelly coat formation( 0- 160m) and mature egg w ith germinal vescle disappeared ( 160m) . The spermatocytes underwent 4 stages: cell multiplication, plasmic growth, cell differentiation and maturity. The germ cells were found in the coelom all the time of a year. The spawning of this population in Guangxis sea area took place several times from April to September each year and peaked from May to August. Key words: Sip unculus nudus; development of germ cells; spawning; reproductive cycle ( Sip unculus