Licea castanea G. Lister, J. Bot.

Basanta, Diana Wrigley De, Mier, Carlos De & Lado, Carlos, 2023, A taxonomic revision of the species of Licea subg. Licea (Myxomycetes), Phytotaxa 629 (2), pp. 95-128 : 103-105

6. Licea castanea G. Lister, J. Bot. 49: 61 (1911) Figs. 6A–S

= Licea bryocorticola A. Kuhnt, Ber. Bayer. Bot. Ges. 91: 181 (2021), syn. nov. (Holotype see below).

Sporophores sporocarpic, dispersed or grouped, sessile. Sporocarps subglobose, 0.13–0.25 mm diam., to elongated, 0.3–0.7 mm × 0.2–0.25 mm broad, chestnut brown with definite lighter lines of dehiscence. Peridium somewhat cartilaginous, colourless to pale purplish by TL, overlaid with layer of minute bright brown granules ( Fig. 6 E ); dehiscence into platelets along lighter lines with slightly thickened minutely toothed margins. Spores free, pale olive in mass, almost colourless to yellow brown by TL, smooth, 8–10(–12) µm diam., spore wall thinner on one side. By SEM the inner layer of the peridium is smooth with dispersed tiny granules, and the platelet margins have a single row of outgrowths of up to 1 µm diam. ( Fig. 6 I ); the epispore is smooth with fine stippling of irregularly spaced flat warts visible only at very high (5000×) magnification ( Figs. 6 H, J ).

Material examined: Lectotypus. UNITED KINGDOM . Scotland, Aberdeen, Lesmoir, 57.1526ºN 2.1100ºW, on bark of Pyrus aucuparia , Nov 1911, leg. W. Cran, BM 3025 ( BM 001089212!, see Lado & Wrigley de Basanta 2018) . SPAIN. Guadalajara, Tamajón, ermita de la Virgen del Enebral, 30TVL7941, corteza de Juniperus thurifera vivo, cultivado, leg. F. Pando, 203 Pando, 17-II-1986, MA-Fungi 16013 . Guadalajara, carretera a Tamajón, km 29, 30TVL 8326, 900 m, corteza de Juniperus oxycedrus , 15-V-1980, leg. C. Lado, 224 Lado, MA-Fungi 29564 (Rev. NENB 5-12-VII-1982) . Guadalajara, Anchuela del Campo, 30TWL8343, corteza de Juniperus thurifera , 21-XI-1984, Leg. C. Lado et al., 123 Lado, MA-Fungi 15932 . GERMANY. Bayern, München, Stadtbezirk, Schwanthalerhöhe, Giesserweg, neben dem Sportplatz/Spielplatz, 530 m, MTB 7835/314, kleiner Park, Baumallee, auf mit Algen und etwas Moos bewachsener Rinde von lebendem Spitzahorn ( Acer platanoides ), in ca. 150–180 cm Höhe, 13-11-2020, HK 201113-07a (M-0313079)! (as holotypus of Licea bryocorticola ) .

Habitat: on bark of living and dead trees, trunks and stumps of angiosperms and gymnosperms, between mosses.

Distribution: Norway, Sweden, Finland, Russian Federation, Ukraine, Denmark, Netherlands, Belgium, Germany, Poland, United Kingdom, Ireland, France, Switzerland, Austria, Spain, Hungary, Greece, Türkiye, India, Thailand, Japan, Canada, USA, Mexico, Peru, Brazil, Paraguay, New Zealand.

Icon.: Lister (1925: pl. 219, Figs. e–g), Martin & Alexopoulos (1969: 481: Pl. I: 5a–f), Nannenga-Bremekamp (1965: 135, Figs. 3 A – B ; 1975: 62; 1991: 41), Neubert et al. (1993: 149, 282, Pl. V: 3), Lado & Pando (1997: 114, Figs. 27a–b), Yamamoto (1998: 130, Figs. A – B; 2021: 140, Figs. A – D), Härkönen & Sivonen (2011: 52, Fig. 63), Härkönen & Varis (2012: 146, Fig. 214), Poulain et al. (2011: 66), Ronikier et al. (2017: 248, Figs. 1 E – H ), Kuhnt (2021: 182: Figs. 47a–b; 183: Figs. 48a–d; 184: Figs. 49a–d; 185: Figs. 50a–d; 186: Fig. 51b, d, all as L. bryocorticola ; 186: Fig. 51a–c; 187: Figs 52a–d, all as L. castanea ), Bortnikov et al. (2022: 27, Figs. 5a–i ).

Notes. L. castanea was found by the Rev. W. Cran at Lesmoir, Aberdeenshire, Scotland where it occurred on moss growing on the bark of Pyrus aucuparia and also on the bark itself, according to G. Lister (1911: 61). In the box of the type specimen ( Fig. 6 A ) there is a plentiful collection of sporocarps of different sizes. This type material was examined and compared with the description and excellent iconography of L. bryocorticola A. Kuhnt ( Kuhnt 2021) to check if they are conspecific. We repeated light micrographs of the latter ( Figs. 6 K – S ), to compare the colours with the same instruments. Macroscopically the two species are very similar, and both appear on bryophytes and bark. Microscopically both species have a single line of outgrowths on the platelet edges visible by TL and by SEM. Both species have smooth spores with a large pale area, as seen under TL, and the epispore of both species is smooth, with fine stippling at very high magnification by SEM. The differences separating the two species, according to Kuhnt (2021), include slightly darker peridium, slightly darker spore mass and smaller outgrowths on the margins of the platelets. However, our examination of the two species did not corroborate these differences, and since the stated variations are very minor, our opinion is that they do not warrant the creation of a separate species. Therefore we synonymize them here.

The regulations of the BM herbarium discourage use of the sporocarps of the historic collection of L. castanea for SEM analysis, so for the micrographs we used a typical collection from our herbarium.

Licea castanea differs from L. testudinacea Nann. -Bremek. and L.minima Fr. by the chestnut colour of the sporocarps, not dark brown, and in the pale smooth spores, not warted, as in the above-mentioned two species, nor grey or red-brown as in L. testudinacea or L. minima respectively.

Figures

FIGURE 1. Licea alpina. A–F (AH 28531, Holotype).A. Herbarium boxes and slides. B–D. Stalked and subsessile sporocarps. E. Spores and peridial platelets by TL. F. Spores by TL. Scale bars: B–D = 0.1 mm, E–F = 10 µm.

FIGURE 3. Licea aurea. A–G. (dwb 3815, MA-Fungi 91750, Holotype), H–J. (dwb 3533). A. Herbarium box. B–D. Sporocarps. E. Whole sporocarp and spores by TL. F. Fragment of the inner surface of the peridium and spores. G. Spores by TL with thick walls and thinner germination area. H. Whole open sporocarp showing spores by SEM. I. Group of spores by SEM. J. Spore by SEM. Scale bars: B–D = 0.1 mm, E–G, I = 10 µm, H = 50 µm, J = 5 µm.

FIGURE 5. Licea capacia. A–I (12486.Oltra, AH 42711, Holotype).A. Herbarium box. B–D. Sessile sporocarps. E. Peridial platelets by TL. F. Angular spores by TL. G. Peridial platelet margins by SEM showing double peridium (arrow) and no outgrowths. H–I. Spores by SEM. Scale bars: B–D = 0.1 mm, E–F = 10 µm, G–I = 5 µm.

FIGURE 6. Licea castanea. A (BM 3025, BM001089212, Lectotype); B–G (MA-Fungi 16013); H, J (MA-Fungi 29564); I (MA-Fungi 15932); K–S (Holotype of L. bryocorticola, HK 201113-07a, M-0313079). A. Herbarium box. B–D. Sessile sporocarps. E. Spores and peridial platelets by TL showing outgrowths on the edges. F–G. Spores by TL. H. Spore by SEM. I. Peridial platelets by SEM, showing outgrowths along the margins. J. Spore by SEM. K. Herbarium specimen. L–N sessile sporocarps. O–Q. Peridial platelets by TL showing outgrowths on the edges. R–S. Spores by TL. Scale bars: B–D, L–N = 0.1 mm, E–G, P–S = 10 µm, H–J = 5 µm, O = 20 µm.