Lamproderma arcyrionema Rostafiński (1874: 208)

Ronikier, Anna, 2022, Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity, Phytotaxa 531 (3), pp. 175-210 : 182-183

Lamproderma arcyrionema Rostafiński (1874: 208) . Fig. 6

Sporocarps scattered, stipitate, total height 1.10–2.06 mm. Sporotheca globose, 0.36–0.60 mm high, 0.36–0.62 mm diam ( Fig. 6A ). Hypothallus red brown, discoid. Stalk long, 3/5 to 7/9 of the total sporocarp height, 0.70–1.46 mm long, black, shining ( Figs 6A–B ). Peridium persistent, dehiscing in large patches, remaining as a collar at sporotheca base, sometimes peridium breaks first and collar is visible under closed sporotheca, surface rough, golden, sometimes with violet reflections also when spores are blown out ( Figs 6A–B ), pale brown and rough from brownish pigment in transmitted light, pitted. Columella reaching about one-half of the sporotheca height, divided at apex into several primary branches of the capillitium ( Fig. 6C ). Capillitium moderately dense, brown when spores are blown out, darker, blackish brown in central part, fragile, easily breaking during preparation, uniformly dark brown in transmitted light, primary branches about 3–5 μm wide, smooth or only slightly roughened, in peripheral part threads about 1 μm wide, ends wavy, looped and rough. Spores brown in mass, pale grey brown in transmitted light, uniformly coloured, globose or subglobose, (6.5)7–8.5 μm in total range, 7.60 ±0.5 μm on average ±SD (n = 60), covered with warts and groups of darker and larger warts ( Figs 6D–E ), pilate by SEM, pilae with rounded apex covered with wartlets ( Figs 6F–G ).

Material examined:— USA. Whatcom Co.: 2 miles E. of Glacier, on decayed wood, 17 June 1968, DTK 8878 (as L. arcyrionema, UC 1408266!); DTK 8883 (as L. arcyrionema, UC 1408236!); Siskiyou Co.: Panther Meadows Campground, 7600 ft., 25 June 1966, DTK 3682 (as L. arcyrionema, UC 1445742!).

Notes:— Lamproderma arcyrionema was interpreted by Kowalski (1970a) in the present sense: as non-nivicolous species with columella divided at the apex into primary branches, with entirely dark brown capillitium with looped threads at extremities, and with spores ornamentation in the form of warts and groups of larger, darker warts ( Poulain et al. 2011). All Kowalski’s (1970a) specimens of that species were confirmed to be L. arcyrionema ( Fig. 1 ). The species is cosmopolitan in distribution ( Poulain et al. 2011).

Figures

FIGURE 1. List of species identified: left column—original identifications by Kowalski (1970a), right column—updated list of species after revision of examined collections.Green—identification of all specimens confirmed,yellow—identificationof all specimens corrected, blue—some misidentifications noted (the species present before and after revision, but based on different collections), grey—collection too scanty for a proper identification to species. Dotted line—species noted as admixture to another species.

FIGURE 6. Lamproderma arcyrionema Rostaf.A. Sporocarp (note long stalk and golden colours). B. Open sporocarp with visible collar at the base of the sporotheca. C. Columella and capillitium in transmitted light (note dark brown capillitium originating from the top of the columella by primary branches). D. Spores in transmitted light (edge view). E. Spores (top view, note groups of larger warts). F. Spores by SEM. G. Details of spore ornamentation by SEM. Bars: A–B = 1 mm, C = 100 μm, D–E = 10 μm, F = 5 μm, G—2 μm. A: coll. DTK 8878, B–G: coll. DTK 8883.