Letendraea eurotioides Sacc., Michelia 2(6): 73 (1880)
Index Fungorum number: IF 157166; MycoBank number: MB 157166; Facesoffungi number: FoF 00045
Saprobic in terrestrial habitats. Sexual state: Ascomata 100–130 µm diam., semi-immersed to superficial, globose to subglobose, solitary, bright coloured, with papillate, central ostiole (from illustration). Hamathecium of dense, filliform, hyaline pseudoparaphyses. Asci (63-)73–75 × 13–18 µm(x̅ = 71 × 15 µm, n = 8), 8-spored, bitunicate, fissitunicate, cylindrical-clavate, slightly curved, sessile. Ascospores 13–16 × 5–6 µm (x̅ = 14 × 5 µm, n = 20), 1–2-seriate, ellipsoidal to fusoid, upper-cell wider toward base narrow and rounded ends, 1-septate, olivaceous brown, guttulate, smooth. Asexual state: unknown.
Material examined – USA, on dead branches of Rubi fruticosi (NY0091436, lectotype).
Fig. 1 Letendraea eurotioides (NY0091436, lectotype). a Semi immersed to superficial, globose-subglobose ascomata. b Hamathecium. c Young and immature asci. d–f Asci with eight spores. Scale bars: a-b = 20 µm, c = 50 µm, d–f = 10 µm, g=20 µm.
Notes – Letendraea is characterized by superficial, globose to conical ascomata, filliform pseudoparaphyses, obclavate to cylindrical, 8-spored asci, and fusoid to oblong, 1-septate ascospores (Saccardo 1880). Because of its similar morphology with Karstenula rhodostoma, Kodsueb et al. (2006b) assigned Letendraea to Melanommataceae. Subsequent multigene phylogenetic analysis indicated that both L. helminthicola(Berk. & Broome) Weese. and L. padouk Nicot & Parg.-Leduc. nested within Montagnulaceae (Schoch et al. 2009; Zhang et al. 2009), thus Zhang et al. (2012) referred Letendraea to Montagnulaceae. In our phylogeny, we obtained the same results and apart from the putative strains of L. helminthicola (CBS 884.85) and L. padouk (CBS 485.70), we included the putative strain of L. eurotioides (CBS 212.31), the generic type of Letendraea in our analysis. Therefore, we treatLetendraea as a separate genus in Didymosphaeriaceae. During our study, we collected a Dothideomycetes species (Letendraea cordylinicola)from living and dead leaves of Cordyline sp. from Thailand, associated with leaf spot disease and showing similar morphology to Wilmiabrasiliensis. Dianese et al. (2001) referred Wilmia in Phaeosphaeriaceae based on morphological characters. Wilmia is similar to other genera in Phaeosphaeriaceae viz. Barria, Lautitia and Metameris, with their didymosporous ascospores and coelomycete asexual morph (Dianese et al. 2001; Zhang 2012). Zhang et al. (2012) tentatively placed Wilmia in Phaeosphaeriaceae as the genus is poorly known and has no supporting molecular phylogenetic evidence, although Zhang et al. (2012) mentioned that the genus might be accommodated in Leptosphaeriaceae based on its dicotyledonous host habit.
Our phylogenetic analysis showed that a novel Letendraea species (Letendraea cordylinicola) was nested within Letendraea in the family Didymosphaeriaceae. Letendraea and Wilmia share similar characters in having immersed to superficial, globose-subglobose ascomata with filliform pseudoparaphyses and ellipsoidal to fusoid 1-septate, olivaceous brown ascospores with a smooth wall. Therefore, based on the morphology of the type species of Wilmia, W. brasiliensisand novel Wilmia-like (Letendraea cordylinicola) species, coupled with molecular data we exclude Wilmia from Phaeosphaeriaceae and transfer it to Didymosphaeriaceae. Furthermore, we propose to synonymize Wilmia under Letendraea by giving priority to the older name. The type species, Letendraea brasiliensis and the novel species L. cordylinicola are described.