Chawanji A S, Hodgson A N, Villet M H
Department of Zoology and Entomology, Rhodes University, P.O. Box 94, Grahamstown 6140, South Africa.
Tissue Cell. 2005 Aug;37(4):257-67. doi: 10.1016/j.tice.2005.03.006.
Mature spermatozoa from four species of platypleurine cicadas (Albanycada albigera, Azanicada zuluensis, Platypleura capensis and P. hirtipennis) were examined by light and electron microscopy. The filiform sperm have a similar ultrastructure in all species but notable variations were found in sperm dimensions. All species produce more than one discrete length of nucleated, motile sperm, a form of polymorphism termed polymegaly. Polymegaly is expressed in two ways: sperm have bi- or trimodal head and tail lengths. The anterior parts of sperm heads are embedded in an elongate homogenous matrix forming a spermatodesm. The conical acrosome is deeply invaginated posteriorly, and sits on top of the nucleus. The acrosomal contents are differentiated internally with an electron-lucent central medulla and a denser cortex. The homogenously electron-dense nucleus is pointed anteriorly and is generally cylindrical, although posteriorly there is a lateral invagination that extends part-way along the nucleus. This invagination houses fine granular material of the centriolar adjunct. Vesicle-like elements that are associated with both the posterior nucleus and the centriolar adjunct are also found within the invagination. Immediately posterior of and adjoining the centriolar adjunct is a pair of mitochondrial derivatives that are elongated and extend for almost the entire length of the tail. The absence of accessory bodies in cicada sperm suggests that within the Cicadomorpha, the families Cicadidae and Cercopidae are closely affiliated.
对四种扁胸蝉（阿尔巴尼亚扁胸蝉、祖鲁扁胸蝉、南非扁胸蝉和多毛扁胸蝉）的成熟精子进行了光学显微镜和电子显微镜检查。丝状精子在所有物种中具有相似的超微结构，但在精子尺寸上发现了显著差异。所有物种都产生不止一种离散长度的有核、可游动精子，这种多态性形式称为多形性。多形性以两种方式表现：精子头部和尾部长度具有双峰或三峰。精子头部的前部嵌入形成精子束的细长均匀基质中。圆锥形顶体向后深深凹陷，位于细胞核顶部。顶体内容物在内部有所分化，有一个电子透明的中央髓质和一个较致密的皮质。均匀电子致密的细胞核向前尖，通常呈圆柱形，尽管在后部有一个侧向凹陷，该凹陷沿细胞核延伸一段距离。这个凹陷容纳中心粒附属物的细颗粒物质。在凹陷内还发现了与细胞核后部和中心粒附属物相关的囊泡状元件。紧接在中心粒附属物后方并与之相邻的是一对线粒体衍生物，它们细长，几乎延伸到尾部的整个长度。蝉精子中没有附属体，这表明在蝉亚目中，蝉科和沫蝉科密切相关。
