关于新对虾属Metapenaeus幼体发育分期的探讨

新对虾属Ｍｅｔａｐｅｎａｅｕｓ为对虾科Ｐｅｎａｉｄａｅ中的重要类群，随着养虾业的发展，新对虾越来越受到重视。在人工育苗中，虾类幼体发育分期对指导生产有现实意义。国外学者Ｍ．Ｓ．Ｍｕｔｈｕ等（１９７８）对近缘新对虾和道氏新对虾的糠虾（Ｍｙｓｉｓ）阶段分为５期，并在第Ⅴ期糠虾幼体之后增加两个中间期，形成Ｎ－Ｚ－Ｍ－Ｉ的“６－３－５－２”模式。作者在中型新对虾的幼体变态实验观察中注意到，糠虾幼体在一次蜕皮后其体长和附肢形态均有渐微的变化，这种形态上的细微差异不宜作为分期的依据，幼体分期的主要依据以蜕皮为标志。因此新对虾属的幼体发育分期可借鉴中国对虾（Ｐｎｕａｅｕｓｏｒｉｅｎｔａｌｉｓ）幼体分期模式划分，即Ｎ－Ｚ－Ｍ为“６－３－３”。

A Discussion on Larval Development by Stages of Metapenaeus

There is a continuous micro metamorphosis in the period of larval development of Metapenaeus. The larva at same stage can be divided into the beginning stage and the end stage, whose body length at the end is longer than that at the beginning. The differences also occur on its morphological feature, i.e. its morphological feature gradually changes between the first molting and the next molting. The larval development of Metapenaeus can be divided into nauplius ( N 1 6 ) , zoea ( Z 1 3 ) and mysis ( M 1 3 ). The larva reaches postlarva stage after 12 moltings.