摘要
在水温28.5-30℃、盐度23.6-25.4条件下，观察了皱肋文蛤（Meretrix lyrata）胚胎、幼虫和稚贝的发育过程。结果表明，皱肋文蛤的胚胎经历桑椹期、囊胚期、原肠胚期等阶段，形成担轮幼虫。根据行为方式和形态特征，其幼虫阶段可分为D形幼虫、壳顶初期幼虫、壳顶中期幼虫、壳顶后期幼虫、变态期幼虫、附着期幼虫。稚贝发育可分为无管期稚贝、单管期稚贝和双管期稚贝。皱肋文蛤幼虫在不同阶段的生活习性逐渐改变，从担轮幼虫至壳顶后期幼虫营浮游生活，变态期和附着期幼虫分别营匍匐生活和附着生活。壳顶初期幼虫出现足原基，壳顶中期和壳顶后期幼虫分别形成平衡囊和鳃丝。稚贝阶段开始从附着生活向埋栖生活过渡。稚贝出现明显的次生壳，无管期稚贝和单管期稚贝的次生壳为红褐色，而双管期稚贝的次生壳为白色。皱肋文蛤从 D 形幼虫发育到附着期幼虫，后者的壳长和壳高分别增至前者的1.77倍和2.10倍；稚贝阶段从无管期发育到双管期，后者的壳长和壳高分别增至前者的3.13倍和3.28倍，显示皱肋文蛤幼虫阶段缓慢生长，稚贝阶段快速生长的特征。
Development of embryo, larvae and spat ofMeretrix lyrata was observed using optical microscope and digital camera with water temperature of 28.5-30℃ and salinity of 23.6-25.4, which would explore features of reproduction and growth, and provide reference for artificial breeding and culture. The results showed that tro-chophore was formed after development of embryo through morula, blastocyst and gastrula stages. According to the behavior and morphology, larval stage of M.lyrata could be divided into D-shaped larvae, early umbo larvae, me-dium-term umbo larvae, post umbo larvae, metamorphosis larvae and attachment larvae. Life habits ofM.lyrata larvaes in different stages changed gradually, including planktonic life style from D-shaped larvae to post umbo larvae, and creeping and attaching life types for metamorphosis larvae and attachment larvae respectively. Forma-tion of foot primordium was in early umbo larvae, and statocyst and gill filament were formed in the stage of me-dium-term umbo larvae and post umbo larvae, respectively. Life type ofM.lyrata spat began to transit from attach-ing life to buried life. Spats appeared obvious secondary shell. The shell color was brown for non siphon stage spat and single siphon stage spat, while was white for double siphon stage spat. By observing the growth of larvae and spat ofM.lyrata, we found that the shell length and shell height increased by 1.77 times and 2.10 times from D-shaped larvae to attachment larvae, respectively. However, the shell length and shell height increased by 3.13 times and 3.28 times from non siphon stage spat to double siphon stage spat, respectively. Therefore, we propose the growth feature of early developmental stages ofM.lyrata, with larvae growing slowly and spat growing rapidly.
出处
《海洋科学》
CAS
CSCD
北大核心
2015年第7期52-59,共8页
Marine Sciences
基金
广东省海洋渔业科技推广专项(A200899E04
A200908E05)
广东省教育厅项目(GCZX-A0909)
