Ophiocordyceps bidoupensis H. Yu, W.Q. Zou & D.X. Tang, 2022

Zou, Weiqiu, Tang, Dexiang, Xu, Zhihong, Huang, Ou, Wang, Yuanbing, Tran, Ngoc-Lan & Yu, Hong, 2022, Multigene phylogeny and morphology reveal Ophiocordyceps hydrangea sp. nov. and Ophiocordyceps bidoupensis sp. nov. (Ophiocordycipitaceae), MycoKeys 92, pp. 109-130 : 109

Ophiocordyceps bidoupensis H. Yu, W.Q. Zou & D.X. Tang sp. nov.

Fig. 3

Etymology.

Bidoupensis, referred to the type species collected from Bidoup Nuiba National Park.

Holotype.

Vietnam, Lintong Province, Bidoup Nuiba National Park, 12°8'9.30"N, 108°31'51.38"E, alt. 1678 m, on larva of Elateridae ( Coleoptera ) buried in soil, emerging from the leaf litter on the forest floor, 16 October 2017, H. Yu (YHH 20036, holotype; YFCC 8793, ex-holotype culture).

Sexual morph.

The stroma grew from the head of the host, solitary, solid, cylindrical, 11.8-22.5 cm long, yellow. Stipe clavate, yellow, curved, 10.7-21.2 cm long, 0.7-0.9 mm wide. Fertile parts cylindrical, yellow, slightly curved, 2.9-11.3 mm long, 0.9-1.6 mm wide. Sterile apices cone, yellow, 2.1-7.2 mm long, 0.2-0.7 mm wide. Perithecia immersed, pyriform to lanceolate, brown-yellow, 213.4-405.9 × 74.8-192.4 μm. Asci hyaline, slender, 116.1-192.7 × 4.8-7.5 μm. Asci cap prominent, capitate, 4.7-6.1 × 3.3-5.4 μm. Ascospores hyaline, filiform, multi-septate.

Asexual morph.

The colony grew slowly on PDA medium. Cultured at 25 °C for about 6 weeks, the diameter of the colony was 38-45 mm, white, aerial mycelium on the surface, slightly convex. The back of the colony was grayish-white, dark brown in the middle. Surface smooth of hyphae, hyaline, septate. Conidiogenous cells cone, hyaline, septate, smooth-walled, forming on hyphae, with a hypertrophic base, tapering abruptly to a thin neck, 13.80-46.4 × 0.42-5.13 μm. Conidia hyaline, oval or briolette, smooth-walled, 2.24-3.61 × 1.49-2.70 μm.

Host.

Larva of Elateridae ( Coleoptera ).

Habitat.

The hosts were buried in soil, and the stroma were found in the leaf litter on the forest floor.

Distribution.

Vietnam.

Notes.

Phylogenetic analyses showed that O. bidoupensis was clustered with O. houaynhangensis , O. brunneipunctata , O. langbianensis , O. cossidarum , and O. furcatosubulata of the O. sobolifera clade (Fig. 1 ). Their hosts were larvae of Elateridae compared to cicada nymph hosts of the other species of the O. sobolifera clade (Table 2 ). Ophiocordyceos bidoupensis was well-supported by bootstrap support and posterior probabilities, and formed a separate subclade with O. houaynhangensis , O. brunneipunctata , O. langbianensis , and O. cossidarum . The morphology of O. bidoupensis was clearly different in shape and size from other species of O. sobolifera clade (Table 2 ). The stroma of O. bidoupensis grew solitary from the head of the host; sterile apices of the stroma were different from the other species.

Figures

Figure 1. Phylogenetic relationships of Ophiocordyceps hydrangea and related species from the five genes dataset (nr LSU, nr SSU, tef- 1 α, rpb 1, and rpb 2) based on ML and BI analyses. Statistical support values of BI posterior probabilities and ML bootstrap proportions (0.5 / ≥ 50 %) are shown at the nodes.

Figure 3. Ophiocordyceps bidoupensis A-C fungus on an Elateridae larva D, E cross-section of the ascoma showing the perithecial arrangement F-H asci I ascospores J, K colony on PDA medium L-N conidiogenous cells and conidia O conidiogenous cells P, Q conidia. Scale bars: 1 cm (A-C); 200 µm (D); 20 µm (E-H); 10 µm (I); 2 cm (J, K); 5 µm (L-Q).