Three new species of Ophiostoma and notes on Cornuvesica falcata

Abstract

Sampling of beetles, beetle galleries, and stained tree tissues by ourselves and others to obtain isolates of ophiostomatoid fungal species yielded three Ceratocystiopsis-like entities. Using partial rDNA sequences, these were previously identified as being different from both each other and all other described species of Ceratocystiopsis and Ophiostoma. As Ceratocystiopsis Upadhyay et Kendrick has been reduced to synonymy with Ophiostoma Syd. et P. Syd., and sufficient dried material is now available, these are described herein as Ophiostoma carpenteri sp. nov., Ophiostoma rollhansenianum sp. nov., and Ophiostoma manitobense sp. nov. We found O. carpenteri to be closely related to Ophiostoma retusum (R.W. Davidson et T.E. Hinds) Hausner et al., and that both species may actually be fungal symbionts and could represent a discrete genus. Although morphologically O. rollhansenianum appears similar to Ophiostoma minutum Siemaszko, a clearly variable species, and O. manitobense to Ophiostoma minus (Hedgc.) Syd. et P. Syd., earlier rDNA data indicate that O. rollhansenianum and O. manitobense are actually more closely related to Ophiostoma coliferum (Marmolejo et Butin) Hausner et al., and Ophiostoma ranaculosum (J.R. Bridges et T.J. Perry) Hausner et al. We also comment on some morphological features that have previously been overlooked or misreported in Cornuvesica falcata (E.F. Wright et Cain) C.D. Viljoen et al., such as the ascospores actually being hyaline and the presence of two distinct Chalara anamorphs.Key words: Ophiostoma, molecular and morphological criteria, Ceratocystiopsis, Cornuvesica.