Pleocatenata chiangraiensis Y.R. Sun, Yong Wang bis & K.D. Hyde, 2022

Sun, Ya-Ru, Liu, Ning-Guo, Hyde, Kevin D., Jayawardena, Ruvishika S. & Wang, Yong, 2022, Pleocatenata chiangraiensis gen. et. sp. nov. (Pleosporales, Dothideomycetes) from medicinal plants in northern Thailand, MycoKeys 87, pp. 77-98 : 77

Pleocatenata chiangraiensis Y.R. Sun, Yong Wang bis & K.D. Hyde sp. nov.

Fig. 2

Etymology.

The epithet referring to the location in which the fungus was collected.

Holotype.

MFLU: 22-0002

Description.

Saprobic on twigs of Clerodendrum quadriloculare and Tarenna stellulata . Asexual morph: Hyphomycetous. Colonies on natural substrate effuse, dark, velvety. Mycelium immersed, composed of septate, branched, hyaline to subhyaline hyphae. Conidiophores macronematous, mononematous, erect, straight or slightly curved, cylindrical, unbranched, robust, 4-6-septate, brown or dark brown, rough, 35-100 µm long, 5.5-8.5 µm wide. Conidiogenous cells monotretic, integrated, terminal, determinate, cylindrical, dark brown. Conidia catenate, formed in acropetal chains of 2-3, straight or curved, obclavate, olivaceous to brown when young, blackish brown when mature, 5-8-euseptate, slightly constricted at septa, distal conidia rounded at apex, truncate at base, intercalary conidia truncate at both ends, with thickened and darkened scars at base or both ends, 34-70 µm long, 6.5-12 µm at the widest. Sexual morph: Unknown.

Culture characteristics.

Conidia germinated on PDA within 12 hours at 26 °C. Germ tubes were produced from both ends. Colony reached 20-25 mm diameter after 4 weeks at room temperature on PDA media. Mycelia superficial, irregularly circular, entire edge, dark brown from above, black from below, pigment produced which turns the media reddish brown.

Material examined.

Thailand, Chiang Rai Province, Mae Fah Luang University , on twigs of Tarenna stellulata , 3 July 2020, Y.R. Sun, MFU5 (MFLU 22-0002, holotype, ex-type living culture MFLUCC 21-0222) . Thailand, Chiang Rai Province, Medicinal Plants Garden , on twigs of Clerodendrum quadriloculare , 7 June 2020, Y.R. Sun, B45 (MFLU 22-0001, living culture MFLUCC 21-0223) .

Notes.

Two isolates collected from different hosts share similar morphology and clustered together in the phylogenic tree. There are no base pair differences in LSU and tef1 -α genes between these two isolates. One base pair and two base pair differences (without gaps) are observed in ITS and rpb2, respectively. Therefore, the two isolates MFLUCC 21-0222 and MFLUCC 21-0223 are identified as conspecific.

Figures

Figure 2. Pleocatenata chiangraiensis (MFLU 22 - 0002, holotype) a host (Tarenna stellulata) b, c colonies on natural substrate d, e conidiophores with conidia f conidiogenous cells g-k conidia l germinated conidium m, n colonies on PDA (upper view and lower view). Scale bars: 1 mm (b); 100 μm (c); 20 μm (d-l).