隆线溞雄体的外部形态结构

在光镜下详细描述了隆线溞雄溞幼体和成体的外部形态,绘制了雄体成体附肢图.在此基础上运用扫描电镜技术观察第一触角生长变化.雄溞的幼体和成体相比,外部形态基本一致,但第一触角、第一胸肢和前胸部壳瓣,随着龄期的增加而相应发生了明显变化,可作为第二性征.第一触角节数增加,长成三节,并且末节成熟时末端呈弯钩形,有短钢毛着生,整个触角能自由活动;胸部前胸角出现凹陷,密生长柔毛;第一胸肢具长鞭毛和壮钩.隆线溞雄溞幼体生长过程中生殖相关器官有明显变化,且这些特征在交配时起到攀附雌体的作用.壳刺长度则显现无规律性变化.

External Morphological Study on the Male Daphnia carinata

To observe the developing process of the male Daphnia carinata and describe the variety of the segments related with reproduction during the development,the external morphology of male Daphnia carinata is observed by optic microscope and scanning electron microscope,also is described in detail.The patterns of the main organs show the important external characters of male body.The body segments of the juvenile have basically accomplished their development in the egg stage.So,the morphological features from the larvas to adults are nearly the same.But the segments related with reproduction have more changes,such as the first antenna,the first thorax limb and the setae growing at the thoracic region,they change with the development of the larvas and can be the secondary sex characteristics.The nodes increase and changed into three.When it becomes an adult,the terminal of the first antenna grows into a hamulus and with short setae inserted in the inturn.The whole first antenna can move freely.At the same period,there is a hollow in the corner of thoracic region,with long and thick soft hair inserted,and long flagellum and strong hammulus on the first thorax limb also appeared,the characteristic organs are all for the male individuals to catch and speel the female individuals when copulating.On the contrary,the organs unrelated with reproduction such as the length of capillus have irregular changes.