Protohydnum pululahuanum (Pat.) Spirin, 2025

Spirin, Viacheslav, Malysheva, Vera, Viner, Ilya, Alvarenga, Renato Lúcio Mendes, Grebenc, Tine, Gruhn, Gérald, Savchenko, Anton, Grootmyers, Django, Ryvarden, Leif, Vlasák, Josef, Larsson, Karl-Henrik & Nilsson, R. Henrik, 2025, Additions to the taxonomy of the Auriculariales (Basidiomycota) with pedunculate basidia, MycoKeys 120, pp. 339-392 : 339-392

Protohydnum pululahuanum (Pat.) Spirin comb. nov.

Fig. 11 M

≡ Tremella pululahuana Pat. , Bulletin de la Société Mycologique de France 9: 138, 1893. Lectotype (selected here, MBT 10025863 ). Ecuador. Pichincha: Quito, Pululahua , decayed branches, II.1892 Lagerheim ( FH 00783541 , studied) .

= Ductifera pululahuana (Pat.) Donk , Taxon 7: 164, 1958.

= Ductifera millei Lloyd , Mycological Writings 5: 711, 1917 (fide Wells 1957).

Description.

Basidiocarps first pustulate, gregarious, ca. 1 mm in diam., then adpressed-orbicular, up to 1 cm in diam., finally fusing together and forming compound crust-like, effused fructifications up to 2 cm in the widest dimension, gelatinous, semitranslucent, cream-coloured to ivory-yellowish or pale ochraceous, 1–2 mm thick, in dry condition brown and crustaceous, margin elevated, partly detaching; lobes rounded or evenly incised, hollow, 0.5–1 mm thick. Hyphal structure monomitic, hyphae hyaline, clamped, thin- to slightly thick-walled; context hyphae interwoven or subparallel, 2–6.5 μm in diam., embedded in gelatinous matrix, subhymenial hyphae predominantly ascending, rather tightly arranged, 1–3 μm in diam. Gloeocystidia abundant to rather rare, hyaline to yellowish or brownish, gradually tapering to the apex, embedded, (55 –) 65–122 (– 172) × (5.0 –) 5.8–11.4 (– 12.3) μm (n = 24 / 3). Hyphidia abundant, richly branched, 0.5–1.5 μm in diam. at the apex, forming a continuous layer up to 30 μm thick. Basidia four-celled, longitudinally septate, ovoid-ellipsoid, sessile, embedded, (12 –) 13.5–17.5 (– 18.5) × (8.9 –) 9.8–13.6 (– 13.8) μm (n = 24 / 3), sterigmata gradually tapering, up to 15 × 2–3 μm. Basidiospores smooth, thin-walled, cylindrical to broadly cylindrical, usually slightly curved, (8.4 –) 8.8–11.8 (– 12.3) × (4.0 –) 4.2–6.5 (– 6.6) μm (n = 90 / 3), L = 10.02–10.34, W = 5.36–5.56, Q’ = (1.5 –) 1.6–2.3 (– 2.8), Q = 1.85–1.93.

Distribution and ecology.

South America ( Ecuador); thin fallen branches of angiosperms.

Remarks.

Tremella pululahuana was described from Ecuador by Patouillard and Lagerheim (1893). Four original specimens (FH) are the source of the species description above, and one of them (with the collecting date indicated on the label) is selected as a lectotype. No sequences of T. pululahuana s. typi are available at the moment, and we therefore combine it in Protohydnum based on morphological evidence, i. e. its high similarity to P. album and P. aureum . Protohydnum aureum clearly differs from both P. album and P. pululahuanum in having larger basidia and basidiospores. Basidiospores of P. pululahuanum are on average slightly longer and wider than in P. album , although their dimensions strongly overlap. Ervin (1956) pointed at macroscopic differences between P. album and P. pululahuanum (both treated under Gloeotromera ), and her observations correspond with our evidence. Basidiocarps of P. pululahuanum are substantially smaller than in P. album and, when fully developed, produce hollow lobes. It seems that yellowish-ochraceous colouration is characteristic of P. pululahuanum from the very beginning (see protologue). Fructifications of P. album are initially white and either remain so or get yellow-brown tints at the very end of their development or after drying. Moreover, mature basidiocarps of P. album are cerebriform, or foliaceous, not adpressed-orbicular or effused as in P. pululahuanum , and they bear entire lobes.

Figures

Figure 11. Basidiospores of: A. Protohydnum album (specimen Miettinen 196583); B. P. aureum (holotype); C. P. elasticum (holotype); D. P. elevatum (holotype); E. P. erumpens (holotype); F. P. galzinii (three left – specimen Miettinen 15900.4, three right – lectotype of S. galzinii); G. P. lactescens (four left – specimen TAAM 192048, three right – holotype of S. lactescens); H. P. livescens (specimen Spirin 13913); I. P. microperum (holotype); J. P. nudum (holotype); K. P. ocellatum (holotype); L. P. pallidum (holotype); M. P. pululahuanum (three left – lectotype, three right – specimen FH 00783538); N. P. sucinum (three left – lectotype of A. brasiliensis, three right – specimen BPI 701268); O. Protomerulius amiliavi (holotype); P. P. deceptorius (holotype). Scale bar: 10 µm.