Taxonomy
Mesophoma H.B. Zhang, A.L. Yang & L. Chen, gen. nov.
Etymology
Greek,. (Meso-) meaning middle, between, intermediate, or moderate. –phoma, referring to the genus Phoma
MycoBank: MB 843556
Type species. Mesophoma speciosa H.B. Zhang et al.
Conidiomata pycnidial, solitary or aggregated, globose to subglobose, black or brown-yellowish, covered with hyphae, superficial or immersed. Ostiole single, slightly papillate. Pycnidial wall consisting of 2–6 layers of cells of textura angularis. Conidiogenous cells phialidic, hyaline, smooth-walled, ampulliform to doliiform. Conidia oblong to cylindrical, obovoid, sometimes slightly curved to reniform, aseptate, smooth, thin-walled, guttulate, hyaline.
Mesophoma speciosa H.B. Zhang, A.L. Yang & L. Chen, sp. nov.
Etymology: Latin, speciosa, meaning splendid, referring to its elegant appearance
MycoBank: MB 843557
Conidiomata pycnidial, solitary or aggregated, globose to subglobose, black or brown-yellowish, covered with hyphae, superficial or semimmersed, 79–156 × 63–168 µm. Ostiole single, slightly papillate. Pycnidial wall consisting of 4–6 layers of cells of textura angularis. Conidiogenous cells phialidic, hyaline, smooth-walled, ampulliform to doliiform, 5–7 × 8–10 µm. Conidia oblong to cylindrical, obovoid, sometimes slightly curved to reniform, aseptate, smooth, thin-walled, guttulate, hyaline, 3–6 × 1–2 µm, aggregated in cream masses (Fig. 2).
Cultural characteristics: Colonies on PDA, 84–95 mm diam after 7 d, margin regular, aerial mycelia felted, white to grey. Colonies on OA, 62–67 mm diam after 7 d, margin regular, aerial mycelia felted, grey to reddish brown. Colonies on MEA, 56–69 mm diam after 7 d, margin regular, aerial mycelia felted, black to grey. NaOH (1mol/L) spot test negative on OA (Fig. 2).
Distribution: The Lancang county, Yunnan Province, China.
Habitat: Living in leaf spot of Ageratina adenophora.
Holotype: CGMCC 3.20982, isolated from leaf spots of Ageratina adenophora (Spreng.) R.M. King & H. Rob., 20August 2017, H.B. Zhang, preserved by lyophilization (a metabolically inactive state) in the State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan. GenBank: ITS ON124744, LSU ON124751, rpb2 ON156007 and tub2 ON113859.
Note The new species M. speciosa is genetically distinct from the other genera and M. ageratinae in genus of Mesophoma. Morphologically M. speciosa can be distinguished from them in having smaller conidia and 0 septum, larger conidiogenous cells.
Mesophoma ageratinae H.B. Zhang, A.L. Yang & L. Chen, sp. nov.
Etymology: Latin, ageratinae, referring to the host Ageratina adenophora.
MycoBank: MB 843558
Conidiomata pycnidial, scatteredor aggregated, globose to subglobose, black or yellow, covered with hyphae, superficialor (semi-) immersed, 65–214 × 51–223 µm. Ostiole single, slightly papillate. Pycnidial wall consisting of 3–5 layers of cells of textura angularis. Conidiogenous cells phialidic, ampulliform to doliiform, hyaline, smooth, 5–7 × 6–8 µm. Conidia oblong to cylindrical, obovoid, sometimes slightly curved, or reniform, smooth, thin-walled, guttulate, hyaline, aseptate, 3–5 × 1–2 µm, aggregated in cream masses (Fig. 2).
Cultural characteristics: Colonies on PDA, 84–85 mm diam after 7 d, margin regular, aerial mycelia felted, white to grey. Colonies on OA, 62–67 mm diam after 7 d, margin regular, aerial mycelia felted, grey to leaden-black. Colonies on MEA, 48–50 mm diam after 7 d, margin regular, aerial mycelia felted, grey to leaden-black. NaOH (1mol/L) spot test negative on OA (Fig. 2).
Distribution: Kunming county, Yunnan Province, China.
Habitat: Living in leaf spot of Ageratina adenophora.
Holotype: CGMCC 3.20981, isolated from leaf spots of Ageratina adenophora (Spreng.) R.M. King & H. Rob., 22August 2017, H.B. Zhang, preserved by lyophilization (a metabolically inactive state) in the State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan. GenBank: ITS ON124745, LSU ON124752, rpb2 ON156008 and tub2 ON113860.
Note Phylogenetically, M. ageratinae forms a clade separated from all species previously described. Morphologically, M. ageratinae also can be distinguished from them in having smaller and thinner conidia and 0 septum, larger conidiogenous cells.