S.N. Zhang, Hyde K.D. & Liu J.K. MycoKeys.(2019)
Dothideomycetes, Subclass Pleosporomycetidae
Striatiguttula S.N. Zhang, K.D. Hyde & J.K. Liu, MycoKeys 49: 111 (2019)
Type and marine species:
Striatiguttula nypae S.N.Zhang, K.D.Hyde & J.K.Liu. MycoKeys 49: 112 (2019).
MycoBank: MB828274 Facesoﬀungi: FoF 05034
Saprobic on mangrove palm Nypa fruticans. Sexual morph: Stromata: in vertical section 240–380 μm high, 195–385 μm diameter, ( = 318.2 × 289.0 μm, n = 15), black, scattered, gregarious, immersed beneath host epidermis, and erumpent to superficial, with a papilla or short to long neck up to 550 μm, subglobose or conical, uni-loculate or bi-loculate, coriaceous to carbonaceous, ostiolate, periphysate, papillate and clypeate, glabrous or somewhat interwoven pale brown hyphae or with setae, lying at apex of the neck. Peridium: 9–16 μm thin, composed of several pale brown to hyaline angular cells, compressed and pallid inwardly. Wall of the clypeus composed of brown cells of textura epidermoidea and dark brown host tissue. Wall of the neck with thicker and elongated angular cells. Hamathecium: 1–2 μm wide, trabeculate pseudoparaphyses, septate, branched, filamentous, anastomosing, embedded in a gelatinous matrix. Asci: 64–145 × 8–17 μm, ( = 106.3 × 13.8 μm, n = 30), 8-spored, bitunicate, fissitunicate, cylindric-clavate, pedicellate, apically rounded, with an ocular chamber. Ascospores 18–26 × 4–6 μm, ( = 22.2 × 5.3 μm, n = 50), hyaline to brown, uniseriate to biseriate or triseriate, fusiform, 1–3-septate, constricted at the central septum, the upper middle cell slightly swollen towards the central septum, straight or slightly curved, striate, guttulate, end cells slightly paler, surrounded by a mucilaginous sheath. Asexual morph: Undetermined.
Key to marine species in the genus:
- Ascospores 18–26 × 4–6 μm, host Nypa fruticans nypae
- Ascospores 20–29 × 6–10 μm, host Phoenix paludosa S. phoenicis
Striatiguttula nypae varies in ascomatal appearance, mostly immersed beneath the plant surface, sometimes visible as a papilla or dome-shaped area on the plant surface, and becomes erumpent to superficial, with a papilla or a short to long neck. The typical morphological characters of S. nypae are the appearance of stromata, with interwoven pale brown hyphae or setae at the apex of the neck, and the hyaline to brown, 1–3-septate, fusiform ascospores, striate, guttulate, with slightly paler end cells and a mucilaginous sheath. In comparison to the previously encountered species on Nypa fruticans, and several morphologically similar mangrove fungal species, the striation of ascospores can be a reliable morphological character to distinguish Striatiguttula nypae from Astrosphaeriella nipicola (Hyde and Fröhlich 1998), A. nypae (Hyde 1992a) and Leptosphaeria spp. (Spegazzini 1881, Cribb and Cribb 1955, Hyde et al. 1999, Pang et al. 2011), which are characterized by one or three septa and hyaline or brown ascospores. The presence of erumpent to superficial stromata, the number of septa and size of ascospores in S. nypae are also diﬀerent from Trematosphaeria spp., despite being quite similar in ascospore morphology.
Zhang SN, Hyde KD, Liu JK (2019) Striatiguttulaceae, a new pleosporalean family to accommodate the genera Longicorpus gen. nov. and Striatiguttula gen. nov., from palms in mangrove ecosystem MycoKeys 49: 99-129.
Hyde KD, Fröhlich J (1998). Fungi from palms XXXVII. The genus Astrosphaeriella, including ten new species. Sydowia 50(1): 81–132.
Hyde KD (1992). Fungi from decaying intertidal fronds of Nypa fruticans, including three new genera and four new species. Bot J Linean Soc 110(2): 97.
Spegazzini CL (1881). Fungi Argentini additis nonnullis Brasiliensibus Montevideensibusque. Anales de la Sociedad Cientifca Argentina 12(4): 174–189.
Cribb AB, Cribb JW (1955). Marine fungi from Queensland-1. University Queensland Papers, Department of Botany 3: 77–81.
Hyde KD, Goh TK, Lu BS, Alias SA (1999). Eleven new intertidal fungi from Nypa fruticans. Mycol Res 103(11): 1409–1422.
Pang KL, Jheng JS, Jones EBG (2011). Marine mangrove fungi of Taiwan. National Taiwan Ocean University.
Striatiguttula nypae (holotype MFLU 18–1576, paratype MFLU 18–1578). a–c. Appearance of stromata on host surface; d–f. vertical section through a stroma g structure of peridium; h. structure of clypeus near the ostiole, composed of epidermoidea cells and host tissue; i. ostiole with periphyses; j. pseudoparaphyses; k. apex of the neck, with somewhat interwoven pale brown hyphae or setae; l–o. ascus; p–s. ascospores; t. ascospore in India ink and presenting a clear mucilaginous sheath; u. germinating ascospore; v. colony on PDA. Scale bars: 500 μm (a), 200 μm (b, c), 100 μm (d–f), 10 μm (g, p–s, u), 20 μm (h, i, l–o, t), 50 μm (k).