Mesophoma H.B. Zhang, A.L. Yang & L. Chen, in Yang, Chen, Cheng, Li, Zeng & Zhang, Curr. Microbiol. 80(4, no. 129): 5 (2023)
Index Fungorum number: IF 843556; MycoBank number: MB 843556; Facesoffungi number: FoF 15901
Etymology – Greek,. meso-, meaning middle, between, intermediate, or moderate. –phoma, referring to the genus Phoma due to its resemblance.
Asexual morph: 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.
Type species – Mesophoma speciosa H.B. Zhang et al.
Note – The Mesophoma is close to Allophoma Qian Chen & L. Cai, Heterophoma Qian Chen & L. Cai and Boeremia, Stagonosporopsis, while distant from Epicoccum. In terms of each locus, the ITS sequence of Mesophoma differs from that of Allophoma (15 bp), Heterophoma (11 bp), Boeremia (9 bp), and Stagonosporopsis (14 bp). The LSU sequence of Mesophoma differs from that of Allophoma (5 bp), Heterophoma (5 bp), Boeremia (10 bp), and Stagonosporopsis (11 bp). The rpb2 sequence of Mesophoma differs from that of Allophoma (135 bp), Heterophoma (101 bp), Boeremia (133 bp), and Stagonosporopsis (138 bp). The tub2 sequence of Mesophoma differs from that of Allophoma (28 bp), Heterophoma (29 bp), Boeremia (26 bp), and Stagonosporopsis (38 bp). Obviously, the rbp2 is the most different among the four loci. Meanwhile, the most related genus is Heterophoma, while the less related one is Stagonosporopsis. Morphologically, conidia of Mesophoma (3–6 × 1–2 μm, 3–5 × 1–2 μm) are smaller than those of Stagonosporopsis (3.5–10 × 1.5–3.5 μm) and Boeremia (2.5–12 × 2–4 μm) (Figs. 2, 3) [7]. Conidia of Heterphoma are 0–1(–2) septate while those of Mesophoma almost all are 0 septate (Figs. 2, 3) [6].
Species