Licea pygmaea (Meyl.) Ing, Trans. Brit. Mycol. Soc.

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 : 118

20. Licea pygmaea (Meyl.) Ing, Trans. Brit. Mycol. Soc. 78(3): 443 (1982) Figs. 17A–L

≡ Licea pusilla var. pygmaea Meyl., Bull. Soc. Vaud. Sci. Nat. 58: 89 (1933)

Sporophores sporocarpic, scattered to gregarious, sessile. Sporocarps subglobose to pulvinate, angular, 0.05–0.1 mm diam., brown. Peridium double, outer layer horny, inner layer membranous; dehiscence into platelets along shiny ridges, platelet margins with prominent outgrowths. Spores free, dark olive to dull dark brown in mass, greenish yellow by TL, globose, 12–13 µm diam., minutely evenly warted. By SEM the inner peridium inner surface is warted with different sized warts and some bare patches ( Figs. 17 I – J ); the platelet margins have different sized outgrowths mostly in a single row but sometimes overlapping, fused and sausage-shaped ( Figs. 17 I – J ); the epispore is covered with flattened bacula evenly dispersed, sometimes two or more fused ( Figs. 17 K – L ).

Material examined: Lectotypus. SWITZERLAND. Vaud, nr. Ste Croix, La Gittaz, 1250 m, OCT 1930. Myxo 055 ( LAU)!. (Designated by Kowlaski, Mycologia 67: 448-494. 1975) .

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

Distribution: Norway, Sweden, Lithuania, Russian Federation, Denmark, Netherlands, Belgium, Germany, Poland, Ireland, United Kingdom, France, Spain, Switzerland, Austria, India, Vietnam, Japan, Congo Democratic Republic, USA, Canada, Mexico, Brazil, Argentina, Paraguay, Australia, New Zealand.

Icon.: Nannenga-Bremekamp (1965: 140, Figs. 7 B – C , as L. pusilla var. pygmaea ; 1975: 66, as L. pusilla var. pygmaea ; 1991: 45, as L. pusilla var. pygmaea ), Gilert (1996: 517, Figs. 1–2 , 5–6 ; 518, Figs. 7–8 , 11–12 ; 520, Figs. 11–12 , 14 , all the images as L. pusilla ), Lado & Pando (1997: 130, Figs. 37a–b), Yamamoto (2002a: 3. Figs. 1 A – D ; 2004: 23, Figs. 3 A – C ; 2006: 35, Figs. 15 A – D ; 2021: 148, Figs. A – D), Poulain et al. (2011: 70), Ronikier et al. (2017: 253, Figs. 4 G – K ), López-Villalba & Moreno (2020: 149, Figs. 3a–d ), Johannesen & Vetlesen (2020: 79, Figs 40 A), Bortnikov et al. (2022: 39, Figs. 15a–k ).

Notes. This species was published by Meylan (1933), as a variety of L. pusilla Schrad. However based on the number of differences between these taxa, such as spore size, spore ornamentation and the peridium, Ing (1982) raised the variety to specific rank (see above). The minute size of sporocarps and the fact that it has been often included as a variety in the species L. pusilla makes the distribution of L. pygmaea unclear. As stated above, we agree with Ing (1982) and consider L. pusilla and L. pygmaea to be separate species based on the differences found by SEM in the ornamentation of the peridium and platelet edges, as well as spore colour and size.

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 2. Licea ampulliformis. A–H, K–M (dwb 1988, MA-Fungi 98835, Holotype), I–J (dwb 2535).A. Herbarium box. B–D. Sessile sporocarps. E. Spores and peridial platelets by TL showing clear margins to the platelets (arrows). F–H. Spores by TL. I. detail of platelet margin showing clear area by SEM (arrow). J. Inner surface of a platelet showing warted surface. K–L Detail of open sporocarp showing platelets and spore by SEM. M. Spores by SEM. Scale bars: B–D = 0.1 mm, E = 20 µm, F–H, L = 10 µm, I–J, M = 5 µm, K = 50 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 4. Licea belmontiana. A–J (NENB-5879, BR-MYC 5020057898868, Holotype). A. Herbarium box. B–C. Sessile sporocarps. D. Peridial platelets by TL. E. Spores by TL. F. Dehisced sporocarp by SEM. G–H. Peridial platelets by SEM showing margins without outgrowths (arrows). I–J. Warted spores by SEM. Scale bars: B–C = 0.1 mm, D–G = 10 µm, H–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.

FIGURE 7. Licea castaneoides. A–I (NENB 16135, ex Y.Y. 6407, BR5020070191601, Holotype). A. Herbarium box. B–C. Sessile sporocarps. D. Peridial platelet and spores by TL. E. Spores by TL. F. Dehisced sporocarp by SEM. G. Platelet by SEM showing double peridium with no outgrowths on the edge. H–I. Spores by SEM. Scale bars: B–C = 0.1 mm, D–F = 10 µm, G–I = 5 µm.

FIGURE 11. Licea mariae. A–H (MYX 11149, Holotype).A. Herbarium fragment. B–C. Sessile sporocarps. D. Peridial platelets by TL. E–F. Peridial platelets with row of conical outgrowths (arrows). G–H. Spores by TL. Scale bars: B–C = 0.1 mm, D–H = 10 µm.

FIGURE 12. Licea mínima.A–B, E. G, I–K (MA-Fungi 23775, Neotype); C–D, F, H (MA-Fungi 17214).A. Herbarium box. B–D. Sessile sporocarps. E–F. Peridial platelets by TL. G–H. Spores by TL. I–J. Detail of inner peridium surface and platelet edges by SEM. K. Spore by SEM. Scale bars: B–D = 0.1 mm, E, I = 20 µm, F–H, J = 10 µm, K = 5 µm.

FIGURE 14. Licea nannengae. A–I (246 Pando, MA-Fungi 16056, Holotype). A. Herbarium box with holotype indicated with arrow. B–C. Sessile sporocarps. D–E. Peridial platelets by TL. F. spore by TL. G. Dehisced sporocarp by SEM. H. Detail of inner peridium surface at platelet edges by SEM. I. Spore by SEM. Scale bars: B–C = 0.1 mm, D–F, H = 10 µm, G = 50 µm, I = 5 µm.

FIGURE 15. Licea nigromarginata.A–D (NENB 13886, BR5020071551626, Isotype).A.Isotype slide.B–D. Spores and peridial platelets by TL. Scale bars: B–C = 50 µm, D = 10 µm.

FIGURE 17. Licea pygmaea.A–L (Myxo 055, LAU, Lectotype).A. Herbarium box. B–E. Sessile sporocarps. F–G. Peridial platelets and spore by TL. H. Whole open sporocarp by SEM. I–J. Peridial platelet margins by SEM. K–L. Spores by SEM. Scale bars: B = 0.1 mm, C–E, H = 50 µm, F–G = 10 µm, I–L = 5 µm.