Calostoma sinocinnabarinum N.K. Zeng, Chang Xu & Zhi Q. Liang, 2022

Xu, Chang, Liang, Zhi-Qun, Jiang, Shuai, Zhang, Ping, Huang, Sheng-Zhuo & Zeng, Nian- Kai, 2022, Notes on two species of Calostoma (Calostomataceae, Boletales) from the south of China, Phytotaxa 533 (1), pp. 49-61 : 57-58

Calostoma sinocinnabarinum N.K. Zeng, Chang Xu & Zhi Q. Liang , sp. nov. ( Figs. 2d–f , 4 , 5d–f )

MycoBank: MB841417

Etymology:—Latin “ sin -” meaning China, holotype locality; “ cinnabarinum ” meaning the surface of peridium colored with a red tint.

Diagnosis:—Characterized by a gelatinous, orange-red to fiery red peridium, a pale orange stipe, broadly ellipsoid basidiospores with prominent reticulations, and a distribution in Asia.

Holotype:— CHINA. Hunan Province: Yizhang County, Mangshan National Nature Reserve, 112°93′21″E, 24°95′67″71 N, elev. 1200 m, 29 July 2019, N. K. Zeng 4157 ( FHMU3739 ). GenBank accession numbers: 28 S = OK147440 , ITS = OK157459 .

Description:— Basidiomata stalked. Peridium subglobose or globose, 1.5–2.5 cm in diam. Exoperidium gelatinous, hyaline, with jelly-like and seed-like appendages when mature, finally falling off. Mesoperidium reddish orange (6A7) when young, then pale brown; surface nearly smooth, then cracked into irregular blocky lobes, finally falling off. Endoperidium red (6B8) to fiery red, velvet. Ostiolum vermilion (9B7), with upraised ridges, star-shaped, teeth 5–8, covered by the exoperidium and mesoperidium when young, exposed when mature. Stipe strongly developed, central, up to 1.8 cm long, about 2 cm wide, consisting of many lines extending from the bottom of the peridium and wrapped by the colloidal exoperidium.

Basidiospores [220/11/4] 10–15(–16) × (8.5–)9–12(–13) μm, Q = (1.00–)1.04–1.50(–1.61), Qm = 1.25 ± 0.14 (including ornamentation), [220/11/4] (7–)8–13(–13.5) × (6–)6.5–9(–9.5) μm, Q = (1.00–)1.06–1.63 (–1.86), Qm = 1.34 ± 0.19 (excluding ornamentation), broadly ellipsoid, with prominent reticulations, hyaline to pale yellow in KOH. Basidia not seen, disintegrating when mature. Exoperidium hyphae long, sparsely branched, gelatinized, hyaline to yellowish in KOH; terminal cells 12–85 × 2–3 μm, thick-walled (1–2 μm). Mesoperidium hyphae yellowish brown in KOH, occasionally branched, with yellowish brown, granular appendages; terminal cells 15–50 × 5–7 μm, slightly thick-walled (0.7–0.9 μm). Stipe hyphae composed of two layers; hyphae in the first layer lemon yellow, with terminal cells measuring 30–65 × 5–8.5 μm, thick-walled (1.5–2 μm); hyphae in the second layer hyaline to pale yellow, with terminal cells measuring 12–49 × 2–4 μm, slightly thick-walled (about 0.4 μm). Clamp connections observed in exoperidium hyphae and the second layer of stipe hyphae.

Habitat:—Gregarious on dark brown soil (pH 5.5) in mixed forests of Lithocarpus spp . and Pinus kwangtungensis Chun ex Tsiang.

Known distribution:—Central China (Hunan Province); eastern China (Jiangxi Province).

Additional specimens examined:— CHINA. Hunan Province: Yizhang County, Mangshan National Nature Reserve , elev. 1200 m, 20 July 2013, S. Z . Huang s.n. ( FHMU1007 ); same location, 29 July 2019, N. K . Zeng 4164, 4167 ( FHMU3732 , 3818 ) . Jiangxi Province: Wuyi Mountain, Tongmuguan , elev. 1080 m, 14 October 1993, M . Zang s.n. ( HKAS27132 ) .

Figures

FIGURE 2. Basidiomata of Calostoma species. a–c Calostoma areolatum (a from FHMU765; b from FHMU2098; c from FHMU2093); d–f Calostoma sinocinnabarinum (d from FHMU1007; e from FHMU3739, holotype; f from FHMU3818). a–e photos by N.K. Zeng; f photo by S.Z. Huang.

FIGURE 4. Microscopic features of C. sinocinnabarinum (FHMU3739, holotype). a. Basidiospores. b. Exoperidium hyphae. c. Mesoperidium hyphae. d. First layer of stipe hyphae. e. Second layer of stipe hyphae. Bars = 10 μm. Drawings by C. Xu.

FIGURE 5. Basidiosporesof Calostoma species fromdry materials underSEM.a–c. C.areolatum (FHMU2089).d–f. C.sinocinnabarinum (FHMU3739, holotype). Bars = 5 μm.