Ophiocordyceps ansiformis Hong Yu bis, D.X. Tang & J. Zhao, 2023

Tang, Dexiang, Zhao, Jing, Lu, Yingling, Wang, Zhiqin, Sun, Tao, Liu, Zuoheng & Yu, Hong, 2023, Morphology, phylogeny and host specificity of two new Ophiocordyceps species belonging to the " zombie-ant fungi " clade (Ophiocordycipitaceae, Hypocreales), MycoKeys 99, pp. 269-296 : 269

Ophiocordyceps ansiformis Hong Yu bis, D.X. Tang & J. Zhao sp. nov.

Fig. 4

Etymology.

Ansi- = handle, formis = forms, the epithet refers to ascospores having a handle-shape.

Diagnosis.

Ophiocordyceps ansiformis differs from closely-related species by producing lanceolate ascospores with a structure resembling a handle-shape in the middle, while O. contiispora produces fusiform ascospores that do not exhibit a similar structure in the middle.

Holotype.

China, Yunnan Province, Jinghong City, Puwen Town. Infected Colobopsis sp. ( Formicinae ) biting into a leaf of Rubiaceae Juss., 22°31'24"N, 100°58'57"E, alt. 1,029 m, 02 October 2022, Hong Yu bis (YHH 2210036 - preserved in the Yunnan Herbal Herbarium).

Description.

Sexual morph: External mycelia produced from all orifices and sutures, brown at maturity. Stroma single, produced from dorsal pronotum, never branched, 25-28 mm in length, cylindrical, dark brown at maturity, light brown at the apical part. Fertile region of lateral cushions, 1-3, hemispherical, 1-1.3 × 0.7-1 mm. Perithecia immersed to partially erumpent, flask-shaped, (174-) 189-290 × 99-126 (-128) μm, with short, exposed neck or ostiole. Asci 8-spored, hyaline, cylindrical, (88-) 92-108 (-112) × 7-10 (-11) μm. Ascus caps prominent, hemispherical, 4-6 (-7) × 2-3 (-4) μm. Ascospores hyaline, thin-walled, lanceolate, having a handle-shape in the middle, 45-59 × 5-6 (-7) μm, 6-9-septate, tapering at apex.

Asexual morph: Hirsutella -A type present along stromata. Phialides lageniform, 15-24 × 3-4 μm, tapering to a short neck, 6-8 μm in length. Conidia were not observed.

Germination process: Ascospores released on agar germinated after 48 h to produce 1-2 capilliconidiophores, (54-) 60-79 (-84) × 0.8-1.4 μm, bearing a terminal capilliconidium, hyaline, smooth-walled, limoniform, 6-10 × 3-4 μm, slightly narrowing apically.

Host: Colobopsis sp. ( Formicinae ).

Habitat.

Subtropical monsoon evergreen broad-leaved forest. Infected Colobopsis sp. biting into a leaf of Rubiaceae Juss., from 0.8 to 1 m above the ground.

Distribution.

China, Yunnan Province, Jinghong City.

Material examined.

China, Yunnan Province, Jinghong City, Puwen Town . Infected Colobopsis sp. biting into a leaf of Rubiaceae Juss., 22°31'24"N, 100°58'57"E, alt. 1,029 m, 02 October 2022, D.X. Tang (YHH 2210007) .

Notes.

Phylogenetic analyses showed that O. ansiformis formed a sister lineage with O. tortuosa and O. contiispora , was clustered in the O. unilateralis core clade, with statistical support from bootstrap proportions (BS = 85%) and Bayesian posterior probabilities (BPP = 95%) (Fig. 1 ). Ophiocordyceps ansiformis was similar to O. tortuosa and O. contiispora in the same host Colobopsis sp. (Fig. 2 ). However, it differed from O. tortuosa and O. contiispora in that it produced lanceolate ascospores and has a handle-shape in the middle (Table 3 ).

Figures

Figure 1. Phylogenetic tree of Ophiocordyceps and related genera, based on the concatenation of LSU, SSU, TEF 1 α, RPB 1 and RPB 2 sequence data. The tree was generated from an alignment of 4,827 sites and 143 taxa (38 within O. unilateralis). The phylogeny was inferred using the IQ-tree. Values at the nodes represent IQ-tree bootstrap proportions (on the left) and posterior probabilities (on the right). All values were shown at the nodes. The scale bar 0.02 indicates the number of expected mutations per site. The two new species were indicated in blue and red font within O. unilateralis core clade. Two species (T. inflatum OSC 71235 and T. ophioglossoides CBS 100239) in Tolypocladium were used as the outgroup taxa.

Figure 2. Phylogenetic tree of some genera of the Formicinae based on COI sequence data. The tree was generated from an alignment of 660 sites and 131 taxa. The phylogeny was inferred using the IQ-tree. Values at the nodes represent IQ-tree bootstrap proportions (on the left) and posterior probabilities (on the right). All values were shown at the nodes. The scale bar 0.05 indicates the number of expected mutations per site. The species (Colonopsis sp. YHH 2210006 and Colonopsis sp. YHH 2210007) are indicated in black and bold font in this work. The Latin name on the right of the tree refers to the pathogenic fungi infecting the host ants and the illustration refers to the fungi infecting ants in the wild. Daceton armigerum USNM was used as the outgroup taxa.

Figure 4. Ophiocordyceps ansiformis a infected Colobopsis sp. biting into a leaf of Rubiaceae Juss b the three ascomata produced from the stroma c, d cross-section of ascomata showing the perithecial arrangement e-h ascus i-k ascospores l-o ascospores with capilliconidiophores p capilliconidium q phialides. Scale bars: 4000 µm (a); 2000 µm (b); 200 µm (c); 100 µm (d); 20 µm (e-h); 10 µm (i, j); 20 µm (k-o); 10 µm (p, q); 5 µm (r).