Peziza elegantula P. A. KARSTEN

Šandová, Markéta, 2015, Type Studies Of Several Species Of Lachnaceae (Ascomycota, Helotiales), Acta Musei Nationalis Pragae Series B 71 (3 - 4), pp. 399-412 : 401-403

Peziza elegantula P. A. KARSTEN ,

Syn. Peziz. Ascob. Fenn., p. 24, 1861.

Pl. 4, Figs 1–15.

D e s c r i p t i o n. Closed dried apothecia ca. 0.2– 0.4 mm in diam., ca. 0.2–0.35 mm high, short-stalked, cupshaped, covered by purplish chestnut hairs, part of apothecium put in KOH 0.55 mm wide and 0.4 mm high, with stalk 0.12 mm long and 0.16 mm wide. Fragment of apothecium released purple-violet colour in 3% KOH (Pl. 4, Fig. 3). Hairs 104–153 × 3.1–3.7 µm on flanks (in KOH or water), 33–48 × 3.0–3.1 µm at margin (in KOH), septate in intervals 10–19 µm on flanks (in KOH), 16–16.5 µm at margin (in KOH), in water hyaline or more frequently with dilute purple-blood red tint, in lower 1 to 3 cells rusty tawny to chestnut, with scattered hyaline or concolorous warts and larger purplish chestnut warts, hair wall in KOH 0.6–0.9 µm thick on flanks. When KOH is added to a water mount, the flank hairs turn green to leaf-green with larger fuscous black warts, marginal hairs dilute green with only concolorous warts, cells of excipulum surface cinnamon to brick, 5–10 × 4–7.5 µm (resp. 4.5–6 µm wide in surface view, 4–7.5 µm wide in median section), hymenium subhyaline with green tint. In preparation to KOH, hairs and hymenium are greenish grey, cells of excipulum surface umber to date-brown, medullary excipulum subhyaline with greenish grey tint composed of cells up to 18 × 2.5 µm, but mostly 1.5–2 µm broad in median section. Hymenium immature, with short, subacute paraphyses 1.5– 2 µm wide (KOH) and a young ascus 32.5 × 4.5 µm (KOH), arising from a crozier, ascus pore with no reaction in MLZ after KOH pretreatment (perhaps because too immature, see also fourth paragraph of discussion).

S p e c i m e n s t u d i e d: Finland, Tavastia , Lempäälä, prope Kukkola (?ca. 8 km N of Lempäälä) , on Epilobium, Sept. 1860 , leg. P. A. Karsten, herb. Karsten ( H) , no. 3377 (holotype).

Additional specimens studied (not included to the description above): U.S.A., Wyoming, Medicine Bow Mts., Nash Fork, on Delphinium subalpinum , 7 Aug. 1950, leg. F. Petrak, PRM 876258, Reliquiae Petrakianae, no. 2021, as Dasyscyphus leucostomus REHM (specimen containing two species, Solenopezia cf. leucostoma (REHM) RAITVIIR and Peziza aff. elegantula ). – Slovakia, Nízke Tatry Mts., in valley Trangoška [near Bystrá], on foot of Veľký Gápeľ, area with calcareous soil, 1600 m a.s.l., on Delphinium sp. , 8 Sept. 1960, leg. M. Svrček, PRM 614196 (specimen containing Solenopezia leucostoma ). – Slovakia, Belianske Tatry Mts., in valley “Kotlina Siedmich prameňov” [near Tatranská Kotlina], on Cimicifuga foetida , 6 Aug. 1956, leg. M. Svrček et J. Kubička, PRM 855801 (specimen containing Solenopezia leucostoma ).

D i s c u s s i o n. The studied holotype specimen clearly compares with the original description ( Karsten 1861). The taxon was originally described as a species possessing purplish blackish-brown, fibrillose striate apothecia with a short stalk or without any stalk (group ‘Substipitatae’ in Karsten’s work), fimbriate margin, bent inwards, and slender paraphyses. Later Karsten’s descriptions, based on more material, refer again to purplish blackish-brown, sessile to short-stalked apothecia ( Karsten 1869, 1871). I studied the holotype because the substipitate apothecia and slender paraphyses seemed to me to indicate that it should be excluded from Trichopeziza in which it had been placed e.g. by Raitviir (1993) and Raitviir and Järv (1997).

Ascospores were not observed during this study of the holotype specimen, neither were they observed in the holotype specimen by Dennis (1956) and Huhtinen (in herb.), and nor were they described in the protologue by Karsten (1861). According to Karsten (1869), the ascospores are fusoid-oblong or fusoid-elongated, non-septate, 6–13 × 2 µm, and the asci cylindrical, 50–70 × 5 µm. According to Dennis (1956), ascospores of the species measure 9–12 × 2 µm, and paraphyses are cylindrical, 1.5 µm wide, pointed at the tip but only slightly longer than the asci. Schmidt and Schmidt (1991) described the ascospores as 10–14 × 1.8 µm and paraphyses cylindrical with pointed tips up to 1.5 µm wide according to material collected in Germany.

The species is unusual in the green colour of its hairs in KOH. This reaction is also known in Solenopezia leucostoma (e.g. Svrček 1988b). I was able to study several specimens of Solenopezia leucostoma deposited in the herbarium PRM, and also North-American material of a species similar to Peziza elegantula but differing from it, e.g., by larger asci, yet being considered as congeneric. The results are presented here: Specimen PRM 876258 from the U.S.A. contains two species, old apothecia of Solenopezia cf. leucostoma and apothecia of Peziza aff. elegantula (Pl. 2, Fig. 13). Solenopezia leucostoma differs from T. elegantula in its darker, urn-shaped apothecia with a conspicuous white collar (white inner margin, PRM 876258, PRM 614196, PRM 855801), filiform paraphyses, asci arising from simple septa, and hyaline, densely warted short hairs (like periphyses) on the inner margin, slightly tapering towards their rounded apex (PRM 614196, PRM 855801).

The Peziza aff. elegantula material, PRM 876258, possesses snuff brown to brown vinaceous apothecia, 0.4– 0.57 mm in diam., 0.33–0.5 mm high in dried state, with flank hairs hyaline with a buff (4D) or dilute pistachio-green tint in KOH, with the basal 2 to 3 cells vinaceous to dark brick, 187–207 × 2.5–3.8 µm, hair wall 0.6–0.7 µm thick, asci 73–87 × 5.8–7.6 µm, arising from croziers, with or without blue reaction of ascus porus in MLZ after pretreatment with KOH (probably according to the developmental stage of the asci), paraphyses cylindrical, septate, anastomosing, 2.0–2.7 µm wide, exceeding the asci by 0–17.5 µm, in lateral part of hymenium branched and with enlarged apices (to 2.5– 2.6 µm). Free ascospores or clearly developed ascospores in asci were not observed. In comparison with the holotype of Peziza elegantula , this specimen has a slightly larger and paler apothecia and slightly longer and narrower hairs. Also the asci are longer in this specimen when compared to the descriptions of P. elegantula by Karsten (1869), Dennis (1956) and Schmid and Schmid (1991).

The transfer of Peziza elegantula to Lasiobelonium in this study is based on the observed structure of the ectal excipulum (Pl. 4, Figs 7, 8), on the fact that the apothecia are stalked (Pl. 4, Fig. 4) and that there was no conspicuously raised margin with densely warted periphysis-like hairs typical of the genus Solenopezia SACCARDO (Pl. 4, Fig. 15). There are, however, several characters which show close affinity to the genus Solenopezia . A green colour of hair in KOH is also known from some species of Solenopezia and from Trichopeziza araliae RAITVIIR ( Raitviir 1995), the position of which requires revision. Species of the genus Solenopezia have, according to Raitviir et al. (1991), a raised excipular margin which is visible and white also in dried apothecia, e.g. in S. leucostoma (PRM 855801; Pl. 2, Fig. 14), but only slightly raised when fresh and incurved when dry in S. lamoureana RAITVIIR ( Raitviir 1995). A raised excipular margin is not present in Peziza elegantula according to microscopic examination in this study. The hairs near the margin (Pl. 4, Fig. 11) are shorter than flank hairs, but they do not differ qualitatively from the flank hairs (both marginal and flank hairs are usually somewhat pointed at the apex and both are in the apical part usually less coloured; no difference in shape of the concolorous warts or striking difference in thickness of the wall were observed). The hairs (Pl. 4, Fig. 6) and the ectal excipulum cells of the holotype specimen are thick-walled when observed in MLZ (Pl. 4, Fig. 10, excipulum near the base of cup). MLZ is probably the medium which was used by Raitviir for microscopic observations (e.g. Raitviir 1973) and the reason why he was describing the hairs of Trichopeziza as smooth ( Raitviir 1987). Solenopezia has a sessile apothecia and cylindrical paraphyses as previously stated ( Svrček 1988b, Raitviir et al. 1991, Raitviir 1993, 1995, 2003), but, e.g., Solenopezia solenia paraphyses are quoted as “cylindrical, pointed” ( Raitviir 1973). Paraphyses of Peziza aff. elegantula which are seemingly mature in the specimen PRM 876258 were not found to be significantly different from S. leucostoma . Raitviir (1980) described the paraphysis range in Lasiobelonium as pointed cylindrical to distinctly lanceolate and he also described the hairs as mostly with brown walls in the basal or the middle part, apically hyaline, rarely totally hyaline. The basal cells of hairs, including the hair wall, in all the material used in this study, were brown according to my observation ( P. elegantula : H 3377; two species in PRM 876258; S. leucostoma : PRM 614196, PRM 855801).

Phylogenetic relationships of Solenopezia and Lasiobelonium still remain unresolved because of the limited number of sequences available in public databases ( Cantrell and Hanlin 1997, Hosoya et al. 2010).

A white collar was not microscopically observed in Peziza elegantula in this study and the genus Solenopezia is defined by the presence of a white collar, and because the shape of the apothecia is different (Pl. 2, Fig. 13), the species is here considered as belonging to Lasiobelonium . A new combination is proposed.

Lasiobelonium elegantulum (P. A. KARSTEN) ŠANDOVÁ , comb. nov. (MycoBank MB 815254) Basionym: Peziza elegantula P.A. KARSTEN, Syn. Peziz. Ascob. Fenn. , p. 24, 1861.