Scanning electron microscopic study of the tegumental surface of adult Schistosoma sinensium.

ABSTRACT

The SEM study of tegumental surface of adult Schistosoma sinensium reveals that the male tegument lacks tubercles or bosses; instead it is corrugated with small pits or perforated ridges. On the dorsal surface, spines are present whose number and size progressively increase towards the posterior end of the body. In addition, there are three types of papillae interspersed among the ridges and spines. The first type of papillae has crater-like holes surrounded by a circular doughnut-shaped elevation; some are ciliated and others are non-ciliated. They are generally found on the dorsal and ventral surfaces. The second is sensory papillae which are hemispherical in shape bearing apical cilia. They are found to be concentrated around the oral sucker and on the posterior end of the worm. The third is fungiform papillae without cilia which are found on the posterior end. There are short spines present on the tegument lining the gynecophoral canal of the male worm. The tegument of the female S. sinensium is corrugated with ridges on the ventral surface. Small spines are present on the anterior portion of the dorsal surface. They become larger and increased in number towards the posterior end of the worm. The three types of papillae are present but they are much fewer and less developed than those in the male worm.