Lineostroma H.J. Swart, Trans. Br. Mycol. Soc.

Jayasiri, Subashini C., Ariyawansa, Hiran A., Jones, E. B. Gareth, Kang, Ji-Chuan, Promputtha, Itthayakorn, Bahkali, Ali H. & Hyde, Kevin D., 2016, Towards a natural classification of Dothideomycetes: 8. The genera Cocconia, Dianesea, Endococcus and Lineostroma, Phytotaxa 255 (1), pp. 66-74 : 69-70

Lineostroma H.J. Swart, Trans. Br. Mycol. Soc. 91(3): 464 (1988)

Type species: Lineostroma banksiae (Cooke) H.J. Swart, Trans. Br. Mycol. Soc. 91(3): 464 (1988)

≡ Didymosphaeria banksiae Cooke, Grevillea 19(no. 92): 90 (1891)

Facesoffungi number: FoF 01293 ( Fig. 2 )

Pathogen on leaves of Banksia , ascomata in necrotic spots on upper surface of living leaves. Sexual morph:

Ascostromata 75–125 μm high, 70–95 μm diam., linear, intraepidermal, at maturity breaking through the upper leaf surface, locules small, containing a few asci between paraphysoid threads, anastomosing, at maturity forming a small apical ostiole. Hamathecium of dense, septate, narrow, trabeculate pseudoparaphyses in a gelatinous matrix. Peridium

15–20 μm wide, inner layer hyaline, outer layer brown, comprising cells of textura angularis to textura globularis. Asci 45–70 × 8–10 μm (x = 53 × 10 μm), 8-spored, bitunicate, cylindro-clavate, short pedicellate, apically rounded, with a minute ocular chamber. Ascospores 21–26 × 3–5 μm (x =23 × 4 μm), uniseriate to biseriate, hyaline, becoming brown when mature, 1-septate, constricted at the septum. Asexual morph: Undetermined.

Material examined:— AUSTRALIA. Victoria: on leaves of Banksia serrata ( Proteaceae ), 1892, Cooke ( K ( M) 143926, holotype).

Notes:— The family Didymosphaeriaceae contains 13 sexual genera and two asexual genera ( Ariyawansa et al. 2014a). Lineostroma banksiae has morphological characters that are distinct to other genera in the family, and hence we place it as a separate genus in the family Didymosphaeriaceae . Lineostroma banksiae is most similar to Phaeodothis in having linear, intra-epidermal ascostromata, trabeculate pseudoparaphyses, asci with a short pedicel and 1-septate ascospores. Phaeodothis tricuspidis differs in ascus arrangement and the peridium comprising hyaline, compressed cells ( Ariyawansa et al. 2014a).

Parmulariaceae E. Müll. & Arx ex M.E. Barr, Mycologia 71(5): 944 (1979)

The family Parmulariaceae was introduced by Müller and von Arx (1962) for taxa with colonies growing on the surface of living plant tissues, mostly leaves, and the family was validated by Barr (1979). The family is clearly polyphyletic and contains a range of ascostromata types, ascomata and even thyriothecia, ascus and ascospore forms ( Inácio & Cannon 2008). Lumbsch & Huhndorf (2010) included 34 genera in the family and Inácio & Cannon (2008) included 59 genera ( Guatimosim et al. 2014).

Figures

FIGURE 2. Didymosphaeria banksiae (holotype). A Herbarium material. B Ascostromata on host surface. C Close up of ascostromata. D, E Section of the ascostromata. F Close up of the peridium. G Peridium. H–J Cylindrical to clavate asci with a small pedicel and ocular chamber. K–M Clavate-fusiform ascospores. Scale bars: D=100 μm, E=50 μm, F=5 μm, G=30 μm, I–L=10 μm.