Curvularia platzii Y.P. Tan & R.G. Shivas

Tan, Yu Pei, Crous, Pedro W. & Shivas, Roger G., 2018, Cryptic species of Curvularia in the culture collection of the Queensland Plant Pathology Herbarium, MycoKeys 35, pp. 1-25 : 1

Curvularia platzii Y.P. Tan & R.G. Shivas sp. nov. Fig. 4 H–I

Type.

Australia, Queensland, Warwick, from leaf spot on Cenchrus clandestinus , 24 Jan. 2001, G.J. Platz (holotype BRIP 27703b, includes ex-type culture).

Description.

Colonies on PDA approx. 2 cm diam. after 7 d at 25 °C, surface dark olivaceous green. Hyphae subhyaline, smooth, septate, up to 3 µm wide. Conidiophores erect, straight to flexuous, geniculate towards apex, uniformly brown, sometimes pale brown towards apex, septate, up to 75 µm long, 5-6 µm wide, swollen at base, 8-10 µm. Conidiogenous cells integrated, terminal or intercalary, with sympodial proliferation, pale brown to brown, smooth, mono- or polytretic, with darkened scars. Conidia fusiform to narrowly clavate, brown, end cells sometimes paler, (65-) 94-105 (-115) × (11-) 12.5-13.5 (-14) µm, 9-13-distoseptate; hila non-protuberant, thickened and darkened.

Etymology.

Named after Gregory (Greg) J. Platz, in recognition of his contributions to Australian cereal plant pathology for the past 30 years, as well as his prowess as an international and Queensland rugby league footballer.

Notes.

The multilocus phylogenetic analyses indicated C. platzii was sister to C. hominis , C. meuhlenbeckiae and C. pisi (Fig. 1). Curvularia platzii is distinguished in one locus from the ex-type culture of C. hominis (97% in tef1α) and in two loci from the reference culture of C. meuhlenbeckiae (99% in gapdh and 99% in tef1α) and the ex-type culture of C. pisi (98% in gapdh and 99% in tef1α). Curvularia platzii differs from C. hominis , C. meuhlenbeckiae and C. pisi , which have much shorter asymmetrical conidia with fewer septa ( Madrid et al. 2014, Marin-Felix et al. 2017a).

Curvularia platzii is only known from the holotype. The host, Cenchrus clandestinus (syn. Pennisetum clandestinus ), is a perennial grass with a worldwide distribution ( Simon and Alfonso 2011). Other Curvularia species associated with C. clandestinus are C. lunata , C. nodulosa and C. trifolii ( Farr and Rossman 2018, Herbarium Catalogue 2017), although these records have not been verified by phylogenetic analyses.