Description of Lanatospora tubulifera sp. n. (Microspora, Tuzetiidae) with Emended Diagnosis and New Systematic Position for the Genus Lanatospora

Abstract

Summary Lanatospora tubulifera , a new microsporidian parasite of the ostracod Acanthocyclops vernalis is described based on light microscopic and ultrastructural characteristics. The diagnosis of the genus is emended and a new family position is suggested. The microsporidium has isolated nuclei at all stages of the life cycle. Merogony gives rise to rounded plasmodia with at least four nuclei. Sporogony produces at least 8 sporoblasts by rosette-like budding. Spores are pyriform, uninucleate and measure 3.5–4 × 2 µm when fixed and stained. The exospore consists of four layers: an electron dense layer, a double membrane-like layer, a moderately dense layer and a thin, electron dense surface layer. The polar filament is isofilar and arranged in 7–9 coils close to the spore wall in the posterior half of the spore. The polaroplast is tripartite, consisting of two lamellar parts and a posterior tubular part. The spores are surrounded by individual sporophorous vesicles, connected to the exospore by tubuli