Polycephalomyces myrmecophilus Hong Yu bis, Z. H. Liu & D. X. Tang

Liu, Zuoheng, Tang, Dexiang, Lu, Yingling, Zhu, Juye, Luo, Lijun, Sun, Tao & Yu, Hong, 2024, Morphology and phylogeny of four new species within Polycephalomycetaceae (Hypocreales) parasitising Ophiocordyceps species, MycoKeys 105, pp. 179-202 : 179-202

Polycephalomyces myrmecophilus Hong Yu bis, Z. H. Liu & D. X. Tang sp. nov.

Fig. 5

Etymology.

myrmecophilus = myrmecophilous, the epithet referred to the species parasitising myrmecophilous Ophiocordyceps species.

Diagnosis.

Polycephalomyces myrmecophilus are similar to that of Po. ramosus regarding the production of two types of conidia, but Po. myrmecophilus differ by α-conidia round or ovoid, β-conidia elliptical.

Holotype.

China, Yunnan Province, Pu’er City, The Sun River National Forest Park , parasitic on Ophiocordyceps acroasca ( Ophiocordycipitaceae ), on insects underside of leaves, with erect stromata, 30 ° 34 ′ 34 ″ N, 101 ° 6 ′ 24 ″ E, alt. 1095 m, 28 September 2020, Hong Yu bis ( YHH 2009001 ) ;

Sexual morph.

Undetermined.

Asexual morph.

Synnemata arising from the Ophiocordyceps acroasca or Colobopsis sp. corpses, tomentose, white. Colonies on PDA growing slowly, attaining a diameter of 1.7–2.1 cm in 3 weeks at 25 ° C, villous, cinerous, and reverse black yellow. Phialides existing in two types: α- and β-phialides. Both types of phialides often reproduce new phialides at their own apices, collarettes not flared, periclinal thickening not visible. α-phialides verticillate and acropleurogenous on conidiophores and solitary on hyphae; lanceolate, tapering gradually from the base to the apex, 6.1–14.5 μm long, 1.4–2.3 μm wide at the base and 0.8–1.8 μm wide at the apex. β-phialides acropleurogenous in whorls of 2–3 or intercalary and terminal on conidiophores and solitary on hyphae; sickle-shaped, tapering abruptly from the base to the apex, 9.8–17.6 μm long, 0.9–1.6 μm wide at the base and 0.4–1.1 μm wide at the apex. α-conidia round or ovoid, and occurring in the conidial mass on the agar or on the final portion of synnemata, 0.4–0.9 × 0.3–0.9 μm; β-conidia elliptical and produced on the surface mycelium of colony, single or multiple, usually in the form of spore balls at the phialidic apex, 0.6–1.3 × 0.3–0.8 μm.

Host.

Parasitic on Ophiocordyceps acroasca and Ophiocordyceps sp.

Distribution.

China, Yunnan Province.

Material examined.

China, Yunnan Province, Pu’er City, The Sun River National Forest Park , parasitic on Ophiocordyceps acroasca ( Ophiocordycipitaceae ), on insects underside of leaves, with erect stromata, 30 ° 34 ′ 34 ″ N, 101 ° 6 ′ 24 ″ E, alt. 1095 m, 28 September 2020, D. X. Tang . Paratype: YHH 2006020 . Culture ex-type: YFCC 09289443 ; Other cultures: YFCC 09289444 .

Notes.

Polycephalomyces myrmecophilus was sister to Cordyceps pleuricapitata (Fig. 1 : BS = 100 %, BPP = 1.00). Po. myrmecophilus was distinct from other species of Polycephalomyces , being parasitic on Ophiocordyceps acroasca and Ophiocordyceps sp. and producing β-phialides sickle-shaped, α-conidia round or ovoid, β-conidia elliptical (Table 3). Thus, Po. myrmecophilus was introduced as a new species under the genus of Polycephalomyces .

Figures

Figure 1. Phylogenetic tree of Polycephalomycetaceae, based on the concatenation of ITS, SSU, LSU, TEF- 1 α, RPB 1 and RPB 2 sequence data. The tree was generated from an alignment of 6,384 sites and 113 taxa. The phylogeny was inferred using the IQ-tree. The Maximum likelihood bootstrap values greater than 75 % (on the left) and the Bayesian posterior probabilities over 0.75 (on the right) were indicated above the nodes. The new species were indicated in back bold font.

Figure 5. Morphological features of Polycephalomyces myrmecophilus (Holotype: YHH 2009001) a overview of Polycephalomyces myrmecophilus and its host b, c colony obverse and reverse d α-phialides f – h β-phialides e α-conidia i β-conidia. Scale Bars: 2 cm (a – c); 20 μm (d – h); 10 μm (i).