Xenochalara, a new genus of dematiaceous hyphomycetes for chalara-like fungi with apical wall building conidial development
South African Journal of Botany
Repub l Jc of South Africa Recf!l\w/0 ' Sovel/1ber 1999: rem'ed 2-1 JanuG/y 2000 Ceratocystis autographa Bakshi IS unu sual amongst the oph!ostomatoid fung i in that it prod uces two distinct anamorphs, typifying differen t teleomorph genera , A ch a l ara~li k e anamorph characteristic of the genus Ceratocystls sensu stricto Ellis & Haist. and a Sporo thrix Hektoen & C F Perkins anamorph typical of the genus Ophiostoma Syd . & P. Syd ., have been described for the fungus. In a recent study, an
... a recent study, an isolate resembling C. autographa , that was collected from JUniperus L , was shown to have a different type of conidiogenesis to that of typica l species of Chalara (Corda ) Rabenh Furthermore, cy cloheximide to lerance and the presence of rhamnose In the cell wa ns of th is isolate also suggested tha t it wa s more closely related to Ophiosfoma than to Ceratocysfis s. sfr. Parsimony analysis of ribosoma l DNA sequence data In th is study showed that this Isolate formed a monophyletic group, distinct from Ceratocystis isolates and from Ophiostoma ulmi (8ulsman) Nannf, Th e chalara~like anamorph from Juniperus IS also distinct from typical Chalara anamorphs of Ceratocystis s. sfr. in that It prod uces con idia from ph ialide s via apical wa ll building , in contrast to the ring wall building typical of Chalara species. We, therefore, propose the establishment of a new genus, Xenoch alara gen nov , for th is and other chalara-Ilke species prod ucing conidia by apical wall building .