异毛虫Allotricha curdsi的形态及形态发生的扫描电镜观察

扫描电子显微镜技术显示:腹毛目纤毛虫异毛虫(Allotricha curdsi)的口围带领部前1片和口围带翻领基部1片小膜由3列纤毛组成,而不同于其他小膜含4列纤毛的情况;在口围带、波动膜及相应皮层区形成小膜侧向纤毛和口盖结构;背皮层背触毛列中每根背触毛的纤毛单元由含纤毛杆的基体和无纤毛杆的裸毛基体组成;形态发生中前仔虫的口围带是由老口围带部分更新而来,并且后仔虫口围带原基在表膜下首先发生,此后突出表膜形成相应的纤毛器原基,经历一系列的发育分化过程而成为新仔虫的纤毛器.此外,将本种纤毛虫与以前报道的Allotricha curdsi(漠河株系)和Pleurotricha curdsi进行了比较.结果表明,腹毛目纤毛虫口皮层和口围带小膜的组成可能具有一些普遍性特征,口皮层和口纤毛器的结构可作为分类标准依据之一;形态发生中不同种类的纤毛虫其皮层纤毛结构的形态发生,可能是在皮层内不同的深度和皮层表面不同的位置启动的;并且,口纤毛结构的起源对纤毛虫的系统学及分类的研究也具有一定的参考价值.

Scanning electron microscopic observations on the morphology and morphogenesis of Allotricha curdsi (Ciliophora:Hypotrichida)

The details of the morphology and morphogenesis of the hypotrichous ciliate Allotricha curdsi was observed with scanning electron microscopy.The result showed that: In the adoral zone of membranelles(AZM) of Allotricha curdsi,the first frontal membranelle and the last ventral membranelle,each consisting of 3 rows of cilia,are quite different from the other membranelles of AZM,which on the contrary,are made of 4 rows of cilia.It was also found that lateral membranellar cilia(LMC) and buccal seal(BS)exist at the cortex between paroral membrane(PM) and AZM,and the kinetosome unit in the dorsal kineties consists of one shafted-kinetosome and another condycondylocilium.During the process of morphogenesis,AZM of the proster would partially regenerate with the old ventral adoral membranelles renewed;whereas,the oral primordium of the opisthe would originated underneath the cell ellicle,protruding from the cell pellicle to form corresponding ciliature primordium,which then developes into new ciliatures through the process of differentiation.Besides,the position and depth where the cortex ciliatures oringinated among species of ciliate are dramatically different.The comparation of Allotricha curdsi and two similar ciliates: Allotricha curdsi and Pleurotricha curdsi indicates that: In the structure of the oral cortex and membranelle,hypotrichous ciliates share same universal characteristic which could be used as a standard in classification.