Chapter 16 - Ascoidea Brefeld & Lindau (1891)

Abstract

This chapter studies the genus Ascoidea. In the determination of asexual reproduction, colonies are smooth, moist or dry, mostly with an expanding, submerged mycelium. Species are often dimorphic, with colonies being restricted and yeast-like or expanding and hyphal. Budding cells and pseudohyphae are present or absent. Wide, true hyphae are present and form blastoconidia, which are sessile or inserted on denticles and occur singly or in short, branched chains. In sexual reproduction, it is seen that asci occur laterally or terminally on hyphae, ellipsoidal or acicular, with firm walls, and contain numerous ascospores, which are liberated through a terminal opening. New asci are formed percurrently inside the remains of a previous ascus. Ascospores are ellipsoidal, with a unilateral, mucilaginous brim. In physiology and biochemistry, it is seen that fermentation is absent. Urease activity is absent too. The diazonium blue B reaction is negative or, rarely, weak. This chapter further examines the phylogenetic placement. The type of species mentioned is Ascoidea rubescens. The species accepted are Ascoidea africana, Ascoidea hylecoeti, and Ascoidea rubescens. The systematic discussion of the species includes growth on 4% malt extract agar, formation of ascospores, CoQ, Mol% G1C, gene sequence accession number, type strain, cell carbohydrates, origin of the strains studied, type strain, systematics, ecology, biotechnology, agriculture and food, and clinical importance.