Laurobasidium hachijoense (Y. Otani, Kakish. & Iijima) Kakish., Nagao & Denchev, 2017

Kakishima, Makoto, Nagao, Hideyuki & Denchev, Cvetomir M., 2017, Laurobasidium hachijoense, comb. nov. (Cryptobasidiaceae) causing aerialroot-like galls on Cinnamomum japonicum in Japan, Phytotaxa 303 (1), pp. 97-100 : 97-99

Laurobasidium hachijoense (Y. Otani, Kakish. & Iijima) Kakish., Nagao & Denchev , comb. nov. ( Figs 2 , 3 )

MycoBank number: MB819172

Basionym: — Exobasidium hachijoense Y. Otani, Kakish. & Iijima, Trans. Mycol. Soc. Japan 26: 166, 1985.

Type: —On Cinnamomum japonicum Sieb. ex Nakai , JAPAN. Tokyo Metropolis: Hachijo Island, 13 July 1984, T. Iijima (TNS-F 51502, holotype!).

Additional specimen examined: —On Cinnamomum japonicum . JAPAN. Tokyo Metropolis: Hachijo Island, 25 May 2001, J. Takeuchi (TSH B 0068), GenBank nos. AB177562, 180359.

Known host and distribution: —On Lauraceae : Cinnamomum japonicum ; known only from the type locality.

Comments: —In the protologue of L. hachijoense ( Iijima et al. 1985) , morphological features of the basidia are described but existence of probasidia are not mentioned. We confirm the presence of probasidia ( Fig. 3 ), similar to that of L. lauri , reported by Begerow et al. (2002).

Large clavarioid galls and narrowly cylindrical clamped hyphae characterize the genus Laurobasidium ( Jülich 1982) but in the case of L. hachijoense , clamped hyphae were not found as reported by Iijima et al. (1985).

Begerow et al. (2002, 2014) separated this genus from Exobasidiaceae and placed it in Cryptobasidiaceae on the base of molecular data and gastroid spolulation, but they pointed out that L. lauri is morphologically similar to the genera of Exobasidiaceae in sorus structures. It sporulates on the surface of the host galls and is similar to the members of Exobasidiaceae , whereas the species of other genera sporulate internally in peripherial lacunae of host galls. Therefore, they suspected that Laurobasidium is phylogenetically placed as an intermediate genus between these families.

Figures

FIGURE 2. A.Aerialroot-like galls of Laurobasidium hachijoense formed on a trunk of Cinnamomum japonicum (Hachijo Island, Tokyo, Japan). B. A long gall consisted of deformed plant tissue and the fungus. Basidia and basidiospores are produced on the surface of the gall.

FIGURE 3. Probasidia (p) and basidia (b) of Laurobasidium hachijoense. A. Probasidium. B. Probasidium with thick wall (arrows) and basidium. C. Basidium with sterigmata (arrows). Bar: 10 μm.