【摘要】 通过实验室研究,对石磺(Onchidiumsp.)胚胎发育过程进行了详细观察,比较了不同水温下石磺胚胎发育的速度,探讨了膜内面盘幼虫孵化出膜的主要条件。结果表明:石磺的胚胎发育过程类似于肺螺亚纲其他贝类,行体内受精,刚产出的卵为受精卵,细胞未进行分裂,卵裂从卵产出体外开始,分别经过卵裂期,囊胚期,原肠期,膜内担轮幼虫期,膜内面盘幼虫期,经过孵化期孵化出膜为自由生活的面盘幼虫期。对各阶段幼体的大小、形状、内部器官等特征以及发育变态过程进行了详细的显微观察和描述。26℃,28℃,30℃3个水温组中,从受精卵到膜内面盘幼虫孵化出膜分别需要300h,290h,288h;发现影响幼虫孵化出膜的主要因素是水温和海水的刺激作用;繁殖盛期卵群工厂化水泥池自然水温孵化时间为10~14d。并报道了水温低于23℃时石磺胚胎停止发育现象。更多还原

【Abstract】 The embryonic development of the sea slugOnchidium sp.was observed and described at 3 temperature groups and the main factors affecting the veliger larva released were also examined in artificial conditions.Results showed: The embryonic development process of sea slug was similar to that of other Pulmonate species.The newly laid eggs were fertilized eggs with no division.They then entered into 7 stages such as the cleavage,blastula,gastrula,intracapsular trochophore,veliger in capsule,hatching or release,and the free-swimming veliger.At water temperatures of 26 ℃,28 ℃ and 30 ℃,it took 300,290,288 hours respectively,of development from the zygote to the free-swimming veliger for the sea slug.The body sizes,shapes,interior structures and the metamorphosis of every period of larvae were also recorded under microscopic observation.It is found that the main factors that affected the release were water temperature and the stimulation of sea water.The ceasing of embryo development was first reported at the temperature of below 23 ℃.更多还原