Studies in the Genus Thelebolus: Temperature Optima for Growth and Ascocarp Development

SUMMARY

Evidence from cultural studies suggests that Thelebolus spp. (sensu Kimbr. & Korf) may be characterized as being either ‘psychrophilic’ or ‘thermophobic.’ Ascocarp size was greatly reduced at temperatures above those allowing for optimal growth (15–20 C). The ability of these fungi to grow and produce ascocarps at 0 C is related to their ecology. No variation was found in the number of spores per ascus in any of our isolates. An attempt is made to clear up some of the confusion that exists concerning the importance of ascospore number as a potential means of delimiting species within this genus. Methods are described by which many of these organisms were isolated into pure culture.