Striatiguttula phoenicis S.N.Zhang, K.D.Hyde & J.K.Liu, sp. nov.

Zhang, Sheng-Nan, D. Hyde, Kevin, Gareth Jones, E. B., Jeewon, Rajesh, Cheewangkoon, Ratchadawan & Liu, Jian-Kui, 2019, Striatiguttulaceae, a new pleosporalean family to accommodate Longicorpus and Striatiguttula gen. nov. from palms, MycoKeys 49, pp. 99-129 : 109-112

Striatiguttula phoenicis S.N.Zhang, K.D.Hyde & J.K.Liu, sp. nov. Figure 4

Etymology.

The epithet referring to the host on which the fungus was collected.

Type.

THAILAND. Ranong: Amphoe Mueang Ranong, Tambon Ngao, on decayed rachis of Phoenix paludosa Roxb. ( Arecaceae ), 6 December 2016, S.N.Zhang, SNT51 (holotype: MFLU 18-1579; isotype: HKAS 97481; ex-type culture MFLUCC 18-0266 = GZCC 18-0008).

Description.

Saprobic on mangrove date palm Phoenix paludosa . Sexual morph: Ascomata in vertical section 195-580 µm high, 135-390 µm diameter, (x̄ = 396.0 × 230.3 µm, n = 15), black, scattered, rarely gregarious, immersed, and erumpent through host epidermis by a papilla or a short neck, ampulliform, subglobose, uni-loculate, coriaceous to carbonaceous, ostiolate, periphysate, papillate, glabrous or somewhat interwoven pale brown hyphae or setae, lying around apex of the neck. Peridium 10-24 µm thin, composed of several pale brown to hyaline cells of textura angularis, compressed and pallid inwardly. Wall of the neck composed thick and elongated angular pale brown to brown cells with hyaline inner layers. Hamathecium of 1-2 µm wide, septate, branched, filamentous, anastomosing, trabeculate pseudoparaphyses, embedded in a gelatinous matrix. Asci 89-141 × 12-18 µm, (x̄ = 120.5 × 15.4 µm, n = 20), 8-spored, bitunicate, fissitunicate, cylindric-clavate, pedicellate, apically rounded, with an ocular chamber. Ascospores 20-29 × 6-10 µm, (x̄ = 24.5 × 7.8 µm, n = 40), hyaline to brown (all cells nearly concolorous), uniseriate to biseriate, fusiform to ellipsoidal, 1-3-septate, constricted at the central septum, the upper middle cell slightly swollen and larger, straight or slightly curved, striate, guttulate, surrounded by an irregular mucilaginous sheath. Asexual morph: Undetermined.

Culture characteristics.

Colonies on PDA attaining 14 mm diam within 21 days at 25 °C under natural light, velvety, centrally raised, greenish grey or greyish olivaceous, reverse dull olivaceous or grey, with a margin of translucent, milky white to hyaline mycelium.

Habitat and distribution.

Inhabiting Thai mangrove forests, Andaman sea (west) coastline, Thailand.

Notes.

The fusiform to ellipsoidal, 1-3-septate ascospores of Striatiguttula phoenicis is similar to those of Trematosphaeria mangrovis , associated with submerged roots of mangrove trees. However, Striatiguttula phoenicis differs from T. mangrovis ( Kohlmeyer 1968) as the latter has larger ascospores and lacks striations (Table 3). Striatiguttula phoenicis is morphologically different from S. nypae as it has ellipsoidal ascospores which are broader in width. Currently, the erumpent to superficial stromata have not been found in S. phoenicis . The phylogenetic analysis also confirms that they are distinct species. There are 26 noticeable nucleotide differences across the 474 nucleotides (Suppl. material 1) of ribosomal ITS sequence data (strains: MFLUCC 18-0266 vs. MFLUCC 18-0265, MFLUCC 17-2517 and MFLUCC 17-2518).