Heterodoassansia morotiana (Zundel) Vánky on Echinodorus ranunculoides (L.) Engelm.
Sori in the leaves, petioles and stems of paludal or aquatic plants, forming pale green, yellowish or brownish areas with numerous spore balls embedded in the host tissue appearing as minute brown dots.
Spore balls rather persistent, consisting of a central mass of spores surrounded by a cortex of sterile cells.
Cortex an external layer of small smooth empty cells and an internal layer of larger empty cells with ornamented inner surfaces.
Host-parasite interaction by complex interaction apparatus with cytoplasmic portions; haustoria absent.
Septal pore simple, with 2 membrane caps.
Heterodoassansia includes eight species that infect hosts in six monocotyledonous and dicotyledonous families across most continents. It is similar to Doassansia, from which it differs by having cortical cells of two kinds around the spore balls. In Australia, Heterodoassansia is represented by a single specimen collected more than 120 years ago.