Comparative Ultrastructural Observations of Spore Wall Structure in Six Species of Echinostelium and Three Species of Eumycetozoa

ABSTRACT

Transmission electron microscopy (TEM) studies reveal that the spore walls of Echinostelium minutum, E. bisporum, E. arboreum, E. coelocephalum, E. corynophorum and Echinostelium sp. consist of two layers: an electron-transparent inner layer and an electron-dense fibrillar outer layer possessing sculptural elements pierced by electron-transparent channels. The TEM studies on Cavostelium apophysatum, Semimorula liquescens and Protostelium mycophaga demonstrate spore walls consisting of a single, electron-dense layer lacking channeled elements. Scanning electron microscopy (SEM) studies on E. minutum, E. arboreum, E. coelocephalum, E. corynophorum and Echinostelium sp. indicate the presence of microverrucate, microechinate or microbaculate sculptural elements on the spore walls.

Key Words:

• Echinostelium
• Cavostelium
• Protostelium
• Semimorula
• spore ultrastructure