Ultrastructural localization of chitin in the cystic wall of Euplotes muscicola Kahl (ciliata, hypotrichia).

The ultrastructural localization of chitin in the cyst walls of Euplotes muscicola was carried out after deproteinization and by specific labelling with WGA-gold complex. The overall ectocyst contains chitin that alone can sustain the exact profile of this cystic layer. In the endocyst, electron clear sublayers include chitin and alternate with other sublayers probably of proteic nature.