Cytospora Tibouchinae Fungal Planet Description Sheets 381

380 Persoonia – Volume 36, 2016

Cytospora tibouchinae Fungal Planet description sheets 381

Fungal Planet 431 – 4 July 2016 Cytospora tibouchinae Crous & M.J. Wingf., sp. nov.

Etymology. Name refers to Tibouchina, the plant genus from which this Notes — Based on ITS sequence data Cytospora tibou fungus was collected. chinae is 98 % (561/575) similar to Cytospora myrtagena Classiﬁcation — Valsaceae, Diaporthales, Sordariomycetes. (CMW4046; GenBank AY347380.1) (Adams et al. 2005, Rossman et al. 2015). Morphologically, Cytospora tibouchinae Conidiomatal (on pine needle agar; PNA) stromata up to 500 µm has conidia of similar dimensions, 3–3.5(–4) × 1 μm, but the diam, rosette cytosporoid, subdivided by invaginations, up to six two species can be distinguished in that C. myrtagena has radially arranged. Conidiophores hyaline, smooth, branched, unbranched conidiophores, and shorter conidiogenous cells, 0–3-septate, 15–25 × 2–3 µm, embedded in a gelatinous 5–7 × 1 µm (Adams et al. 2005). layer. Conidiogenous cells phialidic, with periclinal thickening, tapering towards apices, collarettes minute, 8–14 × 1.5–2 µm. Conidia hyaline, smooth, guttulate, allantoid, aseptate, (3–) 3.5(–4) × 1(–1.5) µm. Culture characteristics — Colonies covering dish after 2 wk at 25 °C, with spreading, flat surface; margins smooth, and with moderate aerial mycelium. On MEA surface grey-olivaceous, reverse greyish sepia. On OA surface olivaceous grey. On PDA surface smoke grey with patches of honey, reverse grey olivaceous.

Typus. France, La Réunion, on stems of Tibouchina semidecandra (Melastomataceae), 12 Mar. 2015, P.W. Crous & M.J. Wingfield (holotype CBS H-22620, culture ex-type CPC 26333 = CBS 141324; ITS sequence GenBank KX228284.1, LSU sequence GenBank KX228335.1, MycoBank MB817050).

Colour illustrations. Tibouchina semidecandra on La Réunion Island; conidiomata sporulating on PNA, conidiophores and conidia. Scale bars = 10 µm.

Pedro W. Crous, CBS-KNAW Fungal Biodiversity Centre, P.O. Box 85167, 3508 AD Utrecht, The Netherlands; e-mail: [email protected] Michael J. Wingﬁeld, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0002, South Africa; e-mail: [email protected] Johannes J. Le Roux & David M. Richardson, Centre for Invasion Biology, Department of Botany & Zoology, Stellenbosch University, Matieland 7602, South Africa; e-mail: [email protected] & [email protected] Dominique Strasberg, Université de La Réunion, UMR PVBMT, Peuplements Végétaux et Bioagresseurs en Milieu Tropical, 15 avenue René Cassin, CS 93002, 97 744 Saint-Denis Messag. Cedex 9, La Réunion, France; e-mail: [email protected]