Neoporphyrellus sinoalboater Yan C. Li, J. Li, Halling, Osmundson & Zhu L. Yang, 2025

Li, Jin, Halling, Roy E., Osmundson, Todd W., Yang, Zhu L. & Li, Yan-Chun, 2025, Global diversity of the Tylopilus alboater complex (Boletaceae, Boletales): new genus and species, and typification of the name Boletus alboater, IMA Fungus 16, pp. e 159676-e 159676 : e159676-

Neoporphyrellus sinoalboater Yan C. Li, J. Li, Halling, Osmundson & Zhu L. Yang sp. nov.

Figs 5, 8e, f

Etymology.

sino (Latin) = China, reflecting that the basidiomata were collected from China + alboater for the similarity of the basidiomata to T. alboater .

Type.

CHINA • Yunnan Province, Lijiang City, Liming Town, Laojunshan , alt. ca 2516 m, 26.8470°N, 99.8502°E, 31 August 2024, Y. C. Li 6989 ( KUN-HKAS 145312 ) .

Diagnosis.

Neoporphyrellus sinoalboater differs from other species of Neoporphyrellus in its gray to brownish gray pileus, whitish to pallid context, whitish to cream and then dirty white or grayish hymenophore, grayish to blackish brown stipe, a trichoderm pileipellis composed of 3.5–7 μm wide filamentous interwoven hyphae.

Description.

Basidiomata medium to large sized. Pileus 3–4.5 cm in diameter, subhemispherical to applanate; surface dry, smooth, gray (5 B 1) to brownish gray (5 B 2), staining reddish brown when bruised; margin slightly extended; context whitish (1 A 2) to pallid (1 A 3), changing to reddish (8 B 4) or brownish red (8 C 4) quickly, and then slowly becoming blackish (19 F 5) when injured. Hymenophore adnate to slightly decurrent, or sometimes slightly depressed around apex of stipe when mature; surface initially whitish (1 A 2) to cream (1 A 3) or dirty white to grayish (4 B 1); pores angular to roundish, up to 1 mm wide, tubes up to 6 mm long, concolorous or a little paler than hymenophoral surface, changing to reddish brown (8 C 3) at first and then becoming blackish when injured. Stipe 5–8.3 × 1–4 cm, clavate to subcylindrical, flexuous, solid, grayish (5 C 3) to blackish brown (5 E 2), dark in color downwards, staining reddish brown at first and then blackish when bruising; context white (1 A 1) to cream (1 A 2), changing to brownish red (8 C 4) quickly, then slowly becoming blackish (19 F 5) when injured; basal mycelium white (1 A 1). Taste and odor mild.

Basidia 25–34 × 9–10 μm, clavate, thin-walled, 4 - spored, hyaline or yellowish brown in KOH. Basidiospores [80 / 4 / 4] (7) 7.5–9.5 (10) × (3.5) 4–4.5 (5) μm, [Q = (1.67) 1.75–2.25 (2.38), Q m = 1.99 ± 0.13], subfusiform in profile view with slight suprahilar depression, elongated to fusiform in ventral view, smooth, slightly thick-walled (up to 0.5 μm), yellowish or brownish in KOH, brown to yellowish brown in Melzer’s reagent. Hymenophoral trama boletoid; hyphae cylindrical, 4–10 μm wide, hyaline to yellowish in KOH, yellow to yellowish brown in Melzer’s reagent. Cheilocystidia 34–55 × 8–14 μm, fusiform or subfusiform, thin-walled, hyaline to brownish in KOH, yellowish brown to brownish in Melzer’s reagent; surface without encrustations. Pleurocystidia morphologically similar to cheilocystidia. Pileipellis a trichoderm, composed of 3.5–7 μm wide filamentous interwoven hyphae, yellowish brown to brownish in KOH and brown to dark brown in Melzer’s reagent; terminal cells 15–88 × 3.5–7 μm, clavate to subcylindrical or fusiform, thin-walled. Pileal trama composed of thin-walled hyphae, 3.5–6 μm wide, hyaline or yellowish in KOH, brownish in Melzer’s reagent. Clamp connections absent in all tissues.

Habitat and distribution.

Solitary on the ground under Quercus semicarpifolia ; currently known from central and southwestern China.

Additional specimens examined.

CHINA • Hubei Province, Shennongjia, Muyu Town , alt. ca 1800 m, 31.4689°N, 110.3663°E, 16 July 2012, Q. Zhao 1556 ( KUN-HKAS 78815 ) ; Yunnan Province, Dali, Xiangyun Town, Dasongping Village , alt. ca 2040 m, 25.6653°N, 100.6955°E, 10 July 2009, N. K. Zeng 297 ( KUN-HKAS 107186 ) ; Lijiang City, Liming Town, Laojunshan , alt. ca 2516 m, 26.8470°N, 99.8502°E, 31 August 2024, Y. C. Li 7010 ( KUN-HKAS 145313 ) .

Note.

Neoporphyrellus sinoalboater is characterized by its gray to brownish gray pileus and stipe staining reddish brown at first and then becoming blackish when bruised; white to cream hymenophore usually staining reddish and then blackish when bruised; white to pallid context changing to reddish or brownish red initially and then slowly becoming blackish when injured; smooth basidiospores; and trichoderm pileipellis. All these features are very similar to those of Abtylopilus scabrosus Yan C. Li & Zhu L. Yang and Abtylopilus alborubellus Yan C. Li & Zhu L. Yang. However , the latter two species have a glabrous pileus, a white to cream or grayish and then grayish pink hymenophore, relatively long basidiospores (up to 11 μm), and a palisadoderm pileipellis composed of broad (up to 9 μm) vertically arranged hyphae ( Li and Yang 2021). Neoporphyrellus alboater and N. atronicotianus share the same discoloration as N. sinoalboater when injured, but N. alboater has a black to dark gray to dark brown pileus becoming gray with age; a dull pinkish or flesh-colored hymenophore; fine hymenophoral pores (up to 0.5 mm wide); relatively large basidiospores measuring 8–11 × 4–5 μm; and wide hymenial cystidia measuring 39–56 × 13–17 μm ( Singer 1947). Neoporphyrellus atronicotianus has a light brown to olive-brown pileus, a grayish to dark brown stipe with the base almost black, relatively long tubes (up to 22 mm), and relatively large basidia measuring 31–46 × 7.5–9.5 μm ( Singer 1947; Bessette and Bessette 2000; Bessette and Bessette 2001; Roody 2003).

Figures

Figure 5. Microscopic features of Neoporphyrellus sinoalboater (KUN-HKAS 107186). a Basidiospores b Basidia, basidioles and pleurocystidia c Pleurocystidia d Cheilocystidia; e Pileipellis. Scale bars: 20 μm.

Figure 8. Basidiomata of “ Tylopilus alboater ” from different regions. a, b N. alboater from North America (NY 1193926, images by Halling) c, d N. atronicotianus from North America (NY 815171, images by Both) e, f Neoporphyrellus sinoalboater from China (e KUN-HKAS 145312, type; f KUN-HKAS 145313) g Abtylopilus australiensis from Australia (NY 2049854, image by Osmundson) h Ab. indonesiensis from Indonesia (NY 1393740, image by Halling) (c – h from https://sweetgum.nybg.org/science/vh/specimen-list/).