The genus Ceratocystis in Ontario

Abstract

From Ontario hardwoods and conifers, 234 collections were examined for Ceratocystis and associated stains and vectors. Most previously described species, including many type specimens, were also studied.Among morphological characters used to separate species of Ceratocystis, those of the ascospores are the most reliable and are stressed in this study. Three-dimensional examination of ascospores, particularly in species possessing spores with sheaths, is necessary to determine spore shape accurately. Four ascospore sheath types are recognized: uniform, hat-shaped, double-brimmed, and quadrangular.A preliminary survey indicates that the bark-beetles Ips pini (Say) and Orthotomicus caelatus (Eich.) may be principal vectors for several Ceratocystis spp. on Ontario conifers.Based mainly on ascospore characters, a key to 60 species of Ceratocystis is provided. The species C. galeiformis Bakshi, C. obscura (Davids.) Hunt, C. polonica (Siem.) Hunt, and C. serpens (Goid.) C. Moreau are excluded. It is proposed that C. ambrosia Bakshi, C. capillifera (Hedgc.) C. Moreau, C. pluriannulata (Hedgc.) C. Moreau, and C. schrenkiana (Hedge.) C. Moreau be considered synonyms of C. pilifera (Fr.) C. Moreau and that C. vesca Davids. be treated as a synonym of C. olivacea (Math.) Hunt. The following species, described since Hunt's key was published, are included: C. bicolor (Davids, and Wells) Davids., C. brevicollis Davids., C. brunnea Davids., C. brunneocrinita Wright and Cain, C. dryocoetidis Kendrick and Molnar, C. europhioides Wright and Cain, C. falcata Wright and Cain, C. huntii Robinson, C. megalobrunnea Davids, and Toole, C. nigra Davids., C. perfecta Davids., C. tremuloaurea Davids, and Hinds, C. truncicola (Davids.) Griffin comb. nov. Eleven new species are described in this paper.Descriptions, figures, and distribution data are provided for most of the 32 species of Ceratocystis encountered in Ontario. The following previously described species were collected: C. bicolor (Davids. and Wells) Davids., C. brunneocrinita Wright and Cain, C. coerulescens (Munch) Bakshi, C. europhioides Wright and Cain, C.fimbriata Ell. and Halst., C. huntii Robinson, C. ips (Rumb.) C. Moreau, C. major (Van Beyma) C. Moreau, C. minor (Hedgc.) Hunt, C. minuta (Siem.) Hunt, C. nigra Davids., C. olivacea (Math.) Hunt, C. perparvispora Hunt, C. piceae (Munch) Bakshi, C. pilifera (Fr.) C. Moreau, C. sagmatospora Wright and Cain, C. stenoceras (Robak) C. Moreau, C. tenella Davids., C. tetropii (Math.) Hunt, C. truncicola (Davids.) Griffin comb, nov., and C. ulmi (Buism.) C. Moreau.The following new species are described by the author: C. acericola, C. allantospora, C. angusticollis, C. capitata, C. crassivaginata, C. dolominuta, C. magnifica, C. ochracea, C. pallida, C. spinulosa, and C. stenospora.