峨眉髭蟾精子形态结构及分类学意义

应用透射电镜、扫描电镜和光学显微镜对峨眉髭蟾(Vibrissaphoraboringii)精子的形态和超微结构研究的结果表明:峨眉髭蟾的精子具角蟾科物种精子基本的形态和结构特征,即精子头部呈螺旋状,尾部呈弯曲状;精子具锥形的顶体、纤维束构成的穿孔器、平行排列的中心粒和双轴丝;线粒体位于尾部;精子核窝不明显、无轴纤维和波动膜等特征。此外,对已有报道的角蟾科和无尾类物种精子的特征进行分析比较表明:(1)角蟾科精子细胞核呈螺旋状,中心粒平行排列,尾部具双轴丝等结构不同于无尾类其他科精子的结构,具有明显的科间差别;(2)角蟾科精子各部的量度,尾部线粒体的分布和数量,以及轴丝的排列等特征在属间和种间表现出明显的差异;(3)峨眉髭蟾和东南亚拟髭蟾指名亚种精子的形态和超微结构存在明显的差异。

Ultrastructure and Morphology of the Spermatozoa in Vibrissaphora boringii and Its Taxonomical Sense (Anura: Megophryidae)

Ultrastructure and morphology of the spermatozoa in Vibrissaphora boringii was studied by light microscopy, transmission and scanning electron microscopy. The structural features of spermatozoa in V. boringii and its taxonomical sense in Vibrissaphora and Megophryidae were discussed. The results show that the sperm of V. boringii present basic morphological and structural characters of Megophryidae by having a spiral head, forniciform tail, conical acrosome vesicle, perforatorium composed of fibers, parallel centrioles, two axonemes and mitochondrion lying in the tail, and lacking distinct nuclear fossa, axial fibers and an undulating membrane. Additionally, comparative analyses of the sperm structure among Megophryidae and other families of tailless Amphibians (Anura) indicates that: 1) The ultrastructural and morphological characters of spermatozoa in Megophryidae, including spiral nucleus, parallel centrioles and two axonemes in the tail, obviously differs from those of the other families of Anura; 2) The distinct differences in size of sperm, the amount and the distribution of mitochondrion, and the range of axonemes also exist among the species and genera of Megophryidae; 3) The ultrastructure and morphology of spermatozoa of Leptobrachium aff. hasselti and Vibrissaphora boringii notably differs from each other.