Ophiocordyceps highlandensis Zhu L. Yang & J. Qin, 2015

Yang, Zhu L., Qin, Jiao, Xia, Chengfeng, Hu, Qun & Li, Qing-Qing, 2015, Ophiocordyceps highlandensis, a new entomopathogenic fungus from Yunnan, China, Phytotaxa 204 (4), pp. 287-295 : 291-292

Ophiocordyceps highlandensis Zhu L. Yang & J. Qin , sp. nov. Figs. 2–4

MycoBank: MB 810173

Etymology: highlandensis refers to habitats of the fungus.

Holotype: CHINA. Yunnan Prov.: Huize County, Jiache Township, Jiache village , 23 July 2014. Z.L. Yang 5797 ( HKAS 83207 ).

Stroma ( Fig. 2 , Fig. 3a ) arising from head of host (larva of Scarabaeidae , Coleoptera ), solitary and simple, 3.5–8 cm in height. Stipe cylindrical, 2.5–6 cm long, 1.5–2.5 mm in diam, dark-brown to blackish, fleshy, glabrous, smooth, enlarging abruptly at fertile portion. Fertile portion single, elliptical to fusiform, 5–15 mm long, 2.5–4 mm in diam, dark brown to fuliginous. Sterile apical portion 5–10 mm long, attenuate towards the apex. Perithecia ( Fig. 4 ) crowded, nearly fully immersed, vase-form, ovoid to oblong, 230–410 × 120–200 μm, oriented at more or less right angles to the longitudinal axis of the stroma; ostioles not protruding; cortex of the fertile portion in transverse section composed of slightly thick-walled (≤ 1 μm thick) yellow-brown cells 7–15 × 5–12 μm. Asci ( Fig. 3b,c ) 8-spored, narrowly clavate to nearly cylindrical, 140–170 × 5–6.5 μm when mature; apex tip 2.5–4.5 μm in height, 4.5–5.5 μm in width, non-amyloid; basal septa with crosiers ( Fig. 3b ). Ascospores ( Fig. 3d ) filiform, 3-septate, rarely 4-septate, 130–150 × 1.5–2 μm, smooth, colorless and hyaline, breaking easily into four (rarely five) part-spores (20)33–55 × 1.5–2 μm. The interior of stipe composed of vertically arranged, frequently septate, slightly thick-walled (≤ 1 μm thick), filamentous hyphae 3–8 μm. Surface of stipe (cortex, Fig. 3e ) a hymeniform layer of cells with brownish to brown vacuolar pigment; terminal cells mostly clavate to narrowly clavate, sometimes subfusiform with an attenuate apical appendage, 10–35 × 3–6 μm. Anamorph not observed.

Habitat and known distribution: On larvae of Scarabaeidae ( Coleoptera ) buried ca 20–40 mm below ground in forests dominated by Pinaceae and Fagaceae at elevation 2200–2300 m in northeastern Yunnan, China.

Additional specimens examined: CHINA. Yunnan Prov.: Huize County, Jiache Township, Jiache village , 27 June 2014. Z.L. Yang 5796 ( HKAS 83206 ) ; Huize County, Shangxiang Township, Malong village , May 2013, Z.L. Yang 5759 ( HKAS 80036 ) .

Figures

FIGURE 2. Stromata of Ophiocordyceps highlandensis and its host (larvae of Scarabaeidae, Coleoptera).

FIGURE 3.Morphological charactersof Ophiocordyceps highlandensis. a.Mature stromataonthe headsof the host(larvaeof Scarabaeidae, Coleoptera). b. Immature asci at different stages of development. c. Ascus with mature ascospores. d. Mature ascospores showing the four part-spores. e. Longitudinal section of stipe, showing the cortex and the interior.

FIGURE 4. A transversal section of the fertile portion of Ophiocordyceps highlandensis, showing the immersed perithecia.