PHRAGMOXENIDIUM-MYCOPHILUM SP-NOV, AN UNUSUAL MYCOPARASITIC HETEROBASIDIOMYCETE

Descriptions are provided of new heterobasidiomycetous taxa, Phragmoxenidiaceae, Phragmoxenidium, and Phragmoxenidium mycophilum. The type species is characterized by intrahymenial growth in fructification of the host Uthatobasidium fusisporum, without developing a basidiocarp. Hyphae and basidia of the parasite attach to host cells and develop a unique host-parasite-interaction. Hyphae are simple septate, the septal dolipores lacking parenthesomes. Transversely septate basidia are 4-celled, each cell provided with one sterigma. Basidiospores germinate by secondary spores or globose microconidia. The interphase spindle pole body resembles the Dacrymyces-type. The combination of taxonomically most important characters, i. e. septal pores, spindle pole bodies, and basidial type, is unique. Therefore, the family is only tentatively included in the Tremellales. © 1990, Gustav Fischer Verlag, Stuttgart · New York. All rights reserved.