Ultrastructural aspects of Myxidium giardi (Myxozoa, Myxosporea), parasite of the European eel Anguilla Anguilla

Abstract

ABSTRACT: The ultrastructure of Myxidium giardi Cepede, 1906 (Myxosporea) from the gills of eels Anguilla anguilla was studied. Sporogenesis complies basically with the pattern known in polysporic myxosporeans, although in this species 1 or 2 spores may be formed within a pansporoblast The valvogenic cells contain 2 kinds of microtubules with diameters of 21 to 25 nm and 15 nm. The suture between the 2 valvogenic cells is formed by a septate desmosome. The sporoplasm, the cell membrane of which may be partly covered by a dense layer, contalns 2 nuclei arranged in a diplokaryon and numerous sporoplasmosomes giving a negative Thiery reaction.