Observations on Gymnoascaceae. V. Developmental Morphology of Two Species Representing a New Genus of the Gymnoascaceae

SUMMARY

Two species, Pseudoarachniotus roseus and P. citrinus, are described as representatives of a new genus of Gymnoascaceae. One of these species, P. roseus, is described as new. The morphological development and other diagnostic characteristics are presented for P. roseus and P. citrinus. In both species the gametangia consist of coiling initials which may be designated as antheridia and ascogonia. From the ascogonium there arise ascogenous hyphae which form asci following production of croziers. The groups of asci which arise are entirely devoid of peridial hyphae. This characteristic lack of a peridium, plus the presence of discrete antheridia and ascogonia, the formation of croziers, and the lack of conidia on phialides, distinguish the new genus, Pseudoarachniotus. The interrelationships of Byssochlamys, Talaromyces, Pseudoarachniotus and Arachniotus are discussed.