Lee Chi-Hoon, Kaang Bong-Kiun, Lee Young-Don
Marine Science Institute, Jeju National University, Jeju 695-965, Republic of Korea.
Department of Biological Sciences, College of National Sciences, Seoul National University, Seoul 151-747, Republic of Korea.
Dev Reprod. 2014 Mar;18(1):25-31. doi: 10.12717/DR.2014.18.1.025.
This study was investigated spawning behavior, structure of egg masses and egg development in Aplysia kurodai inhabiting the coastal waters of Jeju Island, Korea. The mating and courtship behavior of A. kurodai occurred in the form of unilateral copulating with chain formation. In chain copulation, only the first animal acted as a female; the second and succeeding animals acted as males (sperm donors) to the animals in front and as females to the animals behind. The fertilized eggs were packaged in capsules that are embedded in jelly to form a cylindrical string called an egg masses. The number of capsule per cm of the egg masses was 55 to 60 capsules and each capsule within the egg masses held 15 to 25 eggs. After spawning, the egg masses were bright yellow or orange in color. This egg masses color not changed until embryos developed into trochophore stage. Thereafter, as embryo developed from trochophore stage to veliger stage the egg masses color became brownish. The fertilized eggs were spherical, with a diameter of approximately 80±1 μm at spawning. At 5 to 6 days after spawning, the embryo developed into trochophore stage and began to rotate within the egg capsule. In the trochophore stage, the precursor of the velum, called the prototroch or prevelum, developed. At 10 days after spawning, the prevelum is transformed into the velum, and the trochophore developed into veliger stage. Between 10 to 15 days after spawning, the veligers broke out of the egg capsule, and hatched as free-swimming larvae.
本研究调查了栖息于韩国济州岛沿海水域的黑指纹海兔的产卵行为、卵块结构和卵的发育。黑指纹海兔的交配和求偶行为以单侧连锁交配的形式发生。在连锁交配中，只有第一只动物充当雌性；第二只及后续动物对前面的动物充当雄性（精子供体），对后面的动物充当雌性。受精卵被包裹在胶囊中，这些胶囊嵌入凝胶中形成一种称为卵块的圆柱形串状物。每厘米卵块中的胶囊数量为55至60个，卵块内的每个胶囊容纳15至25个卵。产卵后，卵块呈亮黄色或橙色。这种卵块颜色在胚胎发育到担轮幼虫阶段之前不会改变。此后，随着胚胎从担轮幼虫阶段发育到面盘幼虫阶段，卵块颜色变为褐色。受精卵呈球形，产卵时直径约为80±1μm。产卵后5至6天，胚胎发育到担轮幼虫阶段并开始在卵囊内旋转。在担轮幼虫阶段，面盘的前身，称为原担轮或前鳃盖，开始发育。产卵后10天，前鳃盖转化为鳃盖，担轮幼虫发育到面盘幼虫阶段。产卵后10至15天之间，面盘幼虫破囊而出，孵化成为自由游动的幼虫。
