Ascopolyporus tibetensis F.M. Yu, Q. Zhao, and T. Luangharn, 2023

Yu, Feng-Ming, Wei, De-Ping, Zhao, Qi, Tang, Song-Ming & Luangharn, Thatsanee, 2023, Ascopolyporus tibetensis (Cordycipitaceae, Hypocreales): a new species from Tibet, China, Phytotaxa 592 (2), pp. 88-98 : 91-92

Ascopolyporus tibetensis F.M. Yu, Q. Zhao, and T. Luangharn , sp. nov. ( FIGURES 2–3 )

Index Fungorum number: IF900383; Faces of Fungi number: FOF14099.

Etymology:—Named after Tibet Autonomous Region, China, where the type specimen was collected.

Holotype:— CHINA, Tibet, Shigatse City, Nyalam County , on the stems of living bamboo, 27°59′13.313292″ N, 85°59′5.635104″ E, alt. 2291 m, 6 July 2022, Li-Heng Mu, Mu279 ( HKAS 127121 , holotype).

Diagnosis:— Ascopolyporus tibetensis differs from all known Ascopolyporus species by its distinctive appearance of yellow to deep green stromata.

Epibiotic on the living stem of bamboo. Sexual morph: Stromata solitary, bulb-shaped, subglobose to globose, smooth, lower part wrinkles, and comes into contact with the bamboo stems, yellow to olive-yellow on the upper surface, dark turquoise, green to deep green at the lower surface, varying in size, 2–5 cm diam., over 1 mm thick, hollow, containing colorless and odorless liquid, ornamented with irregular stripes on the surface when mature, tough and fleshy when fresh, and hard and unbreakable when dried. Stromatal tissue contains three layers: first, a pare yellow outermost layer nested with gregarious perithecia; second, an internal layer consisting of vertical-arranged, hyaline cells of taxtura intricata; and third, an innermost layer comprised of horizontal-oriented, hyaline cells of taxtura intricata. Perithecia 539–641 × 139–287 μm (mean 600 × 232 μm), ovoid, immersed, with papilla protruding the stroma surface, aggregated. Ostioles papillate, lined with periphyses. Asci 334–443 × 14–31 μm (mean 391 × 20 μm), hyaline, cylindrical, and thickened cap. Asci caps 7.0–10.5 × 2.5–4.0 μm with hemispheric. Ascospores (70–) 105–296 (–339) × 4.0–6.5 μm (Q = 14.36–58.55, n =30), hyaline, whole, filiform, multi-septate, guttulate. Asexual morph: undetermined.

Host and habitat:—Epiphytic on the living stem of bamboo.

Other specimens examined: China, Tibet, Shigatse City , Nyalam County, on the living stems of bamboo, 27°59′13.313292″ N, 85°59′5.635104″ E, alt. 2291 m, 6 July 2022, Feng-Ming Yu, FM 22-182 ( HKAS 127120 ) , Lei Lei , LEI 452 ( HKAS 127119 ) .

Notes: —In phylogenetic analysis, Ascopolyporus tibetensis was closely related to A. galloides , and A. griseoperitheciatus ( Figure 1 ). Based on macro features, such species can be identified by stomata form and color. The stromata of A. galloides and A. griseoperitheciatus are similar in pulvinate shape, while color is different. The upper surface of A. galloides is white to yellowish white, and that of A. griseoperitheciatus is extremely pale violet to light purplish gray. At the lower part of the stromata, A. galloides appears strong orange, but A. griseoperitheciatus shows a vivid yellow to strong orange. Two entomopathogenic fungi A. galloides and A. griseoperitheciatus on scale insects are both epiphytes on living stems and leaves of dicotyledonous plants ( Thanakitpipattana et al. 2022). In our collections, the samples have distinctive characteristics, including the obvious green surface of stromata, which live on bamboo stems. Our sample collections share similar morphological characteristics with A. philodendrus , A. polychrous , and A. villosus in having bulbous stromata, but deeply green-colored stromata are different. The shape and size of perithecia, asci, and ascospores vary significantly among different Ascopolyporus species. The length of perithecia varies from 150 μm in A. griseoperitheciatus to 1 mm in A. polyporoides . The width of asci varies from 2–4 μm in A. purpuratus to 14–31 μm in A. tibetensis , and ascospores range from aseptate to multi-septate, and their width varies from 0.5 μm in A. galloides to 4.0–6.5 μm in A. tibetensis .

Figures

FIGURE 1. Maximum likelihood (ML) phylogenetic tree generated using RAxML, based on the combined ITS, LSU, and tef1 sequence data of Cordycipitaceae. Blackwellomyces calendulinus, B. cardinalis, and B. lateris were used as outgroup taxa here. MLBS (≥70%) and BIPP (≥0.90) are given above the internodes. The type species are indicated in bold, and newly generated sequences in this study are indicated in red.

FIGURE 2. Ascopolyporus tibetensis. a. Habitat. b, c. Stromata growing on a living bamboo in the field. d, e. Stromata after harvested. f. The underside of the fungal stroma removed from the stem. Scale bars: e = 2 cm.

FIGURE 3. Ascopolyporus tibetensis (HKAS 127121, holotype). a. Papilla of peritheicia. b. Cross-section through the stromata shows perithecia. c. Perithecium. d. Internal layer of stromatal tissue. e. Innermost layer of stromatal tissue. f. Ostiole. g. Asci and ascospores. h. Asci. i. Asci cap. j. Ascospores. k. Part of ascospore. Scale bars: a, b = 300 μm, c–e, g= 200 μm, f, h, j = 100 μm, i = 20 μm, k = 30 μm.