Mutinus taishanensis P. M. Wang & Z. L. Zhou, 2023

Zhou, Zhong-Liang, Li, Zhuang, Lyu, Yue, Liu, Ao, Gao, Yi-Ming & Wang, Pan-Meng, 2023, A new species of Mutinus (Phallaceae, Phallales) from Shandong Province, China, Phytotaxa 583 (2), pp. 174-182 : 179

Mutinus taishanensis P. M. Wang & Z. L. Zhou , sp. nov. ( Fig. 2 )

MycoBank no.: MB845687

Etymology:—the epithet, taishanensis , refers to the locality where the type specimen of this species was collected, i.e., Mount Tai (Tai Shan) Scenic Area.

Diagnosis:—Unexpanded basidiome ellipsoid to ovoid, 18–28 × 6–11 mm. Pseudostipe cylindrical, 35–45 × 4–8 mm, apically perforate, sterile portion white red to red, straight, not chambered; fertile portion conical, slightly rugulose, covering about 1/4–1/5 of the total length of pseudostipe. Gleba confined in the upper region of the pseudostipe, mucilaginous. Basidiospores (2.5) 3.0–4.0 (4.2) × 1.5–2 (2.2) μm, ellipsoid, smooth.

Type:— CHINA. Shandong Province: Tai’an City, Zhulin Temple of Mount Tai Scenic Area , on the ground of the forest dominated by Phyllostachys flexuosa and Quercus palustris , elev. 410 m, 7 September 2022, P. M. Wang 077 ( EFHAAU 2894 , holotype!). [GenBank accession numbers—ITS: OQ162322 , LSU: OP584494 , atp6: OP612728 , RPB2: OP612730 ; all from holotype].

Description:— Unexpanded basidiome pyriform to ovoid ( Fig. 2a ), 18–28 × 6–11 mm, epigeous. Expanded basidiome consisting of a pseudostipe and volva. Volva sack-like, composed of exo- and endoperidium. Exoperidium membranaceous, smooth, white (1A1), with several thin white central rhizomorphs emerging from the base. Endoperidium gelatinous, hyaline. Pseudostipe cylindrical, 35–45 × 4–8 mm, acuminate at the apex, apically perforate, hollow, spongy, pale red (9A2) to red (9A6); sterile portion pale red (9A2) to red (9A6), straight, not chambered; fertile portion, slightly thick, conical, rugulose, spongy, 8–12 mm high, covering about 1/4–1/5 of the total length of pseudostipe, usually with a gradually tapered apex, perforated, red (9C4) to dark red (9E8); when fresh covered with gleba in an apical zone. Gleba covering and confined to the upper region of the pseudostipe, mucilaginous, olive green (3E3) to olive grey (3E2). Odor foul and strong while the spore slime is present.

Basidiospores [75/8/4] (2.5) 3.0–4.0 (4.2) × 1.5–2 (2.2) μm, Q = (1.25) 1.5–2.3 (2.67) (Q m = 1.94 ± 0.27), cylindric or subcylindric; ellipsoid ( Fig. 2b ), smooth, hyaline in 5 % KOH. Pseudostipe composed of pseudoparenchymatous cells, hyaline, irregularly shaped, 15.5–52.5 × 18.5–55.5 μm, irregularly subglobose; walls 0.5–1 µm thick; smooth; hyaline in KOH ( Fig. 2c ). Volva formed by filamentous hyphae, septate, branched, hyaline, 2.0–5.0 μm diam., smooth, septate, hyaline in KOH ( Fig. 2d ). Rhizomorphs composed of filamentous hyphae, septate, hyaline, 1.0–5.5 μm diam. ( Fig. 2e ). Clamp connections present in volva and rhizomorphs.

Habitat (Ecology):—Ecology saprobic; growing alone or gregariously on the ground in a forest of Phyllostachys flexuosa and Quercus palustris , widely distributed in Zhulin Temple of Mount Tai Scenic Area in Tai’an City, Shangdong Province, China.

Distribution:—Currently known only from Zhulin Temple of Mount Tai Scenic Area.

Additional specimens examined: CHINA. Shandong Province: Tai’an City, Zhulin Temple of Mount Tai Scenic Area, on the ground of forest dominated by Phyllostachys flexuosa and Quercus palustris , elev. 410 m, 7 September 2022, P. M. Wang 078 and 079 (EFHAAU2895 [GenBank accession numbers—ITS: OQ162323, LSU: OP584495 , atp6: OP612729 , RPB2: OP612731 ] and 2896 [GenBank accession numbers—ITS: OQ162324], respectively); same location, 8 September 2022, P. M. Wang 080 (EFHAAU2897).

Remarks:—The presence of a whitish red to red pseudostipe, a red conical fertile portion (covering about 1/4–1/5 of the total length of pseudostipe), relatively small basidiospores, differentiate M. taishanensis from other species in the genus including M. zenkeri to which it is closely related phylogenetically.

Figures

FIGURE 2. Basidiomata and microstructures of Mutinus taishanensis (holotype, EFHAAU2894). a Basidiomata of Mutinus taishanensis, bar = 10 mm; b Basidiospores, bar = 5 μm; c Pseudoparenchymatous cells of the pseudostipe, bar = 50 μm; d Hyphae of the volva, clamp connection shown in the upper left corner, bar = 10 μm; e. Hyphae of the rhizomorphs, clamp connection shown in the upper left corner, bar = 10 μm. Drawings by Panmeng Wang