Lamproderma echinosporum Meylan (1924: 241)

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 : 188-190

Lamproderma echinosporum Meylan (1924: 241) . Fig. 11

Sporocarps in loose groups or scattered, stipitate, total height 1.50–2.28 mm ( Fig. 11A ). Sporotheca globose or subglogose, 1.00– 1.40 mm high, 1.02–1.40 mm diam, silvery grey with numerous, small, depressed blackish brown patches, with faint colour reflections, brownish at base ( Fig. 11A ). Hypothallus orange brown, discoid. Stalk short to long, 1/4 to 1/2 of the total sporocarp height, 0.40–1.08 mm long, black, tapering upwards ( Fig. 11A ). Peridium persistent, dehiscing irregularly in large patches from apex, often remaining in the lower half of sporotheca, hyaline with blackish brown darker patches in the upper part of sporotheca in transmitted light, often almost uniformly brown at the base of sporotheca ( Fig. 11B ). Columella reaching about one-half of the sporotheca height, cylindrical ( Fig. 11B ). Capillitium originating from the upper half of columella, dense, rigid, pale when spores are blown out, brown in central part and white at extremities, tips white, dark brown with hyaline extremities in transmitted light, with many anastomoses and pointed ends ( Fig. 11B ). Spores dark brown in mass, dark brown in transmitted light, darker at one side, with small to large germ pore and then eyeball-like in shape, globose, (13.5)14–17(18.5) μm in total range, 15.47 ±1.0 μm on average ±SD (n = 150), covered with loosely arranged, long spines about 1 μm high ( Figs 11C–D ), baculate by SEM, baculae coralloid at the top ( Figs 11E–F ).

Material examined:— USA. Tehama Co.: Well’s Cabin Campground, 6300 ft., on dead twigs, 18 June 1966, DTK 3496 together with L. pulveratum (as L. echinosporum, UC 1408226!); 24 June 1967, DTK 6275 (as L. echinosporum, UC 1408213!); Tehama Co.: 6 miles S of Lassen Park, 5800 ft., on dead twigs, 27 April 1968, DTK 8286 together with L. arcyrioides (as L. echinosporum, UC 1408254!); Mt. Rainer National Park, 4 miles S of Cayuse Pass, 3500 ft., on twig, 11 June 1968, DTK 8456, (as L. echinosporum, UC 1408221!); Olympic National Park, 2 miles below Hurricane Ridge, on twig, 22 June 1968, DTK 9262 (as L. echinosporum, UC 1408230!).

Notes:— Lamproderma echinosporum is easy to identify based on peridium with depressed blackish brown patches and large, distinctly spiny spores very often with a large germ pore area. For a detailed description and comments see Kowalski (1970b). All specimens identified by Kowalski (1970a) as L. echinosporum were confirmed to be this species. Interestingly, North American specimens are characterised by long stalk ( Fig. 11A ) what makes them more similar to the South American population (see Ronikier & Lado 2015) than to the European one. The species occurs in Europe, Asia, North America and South America ( Wrigley de Basanta et al. 2010, Poulain et al. 2011, Ronikier & Lado 2015).

Figures

FIGURE 11. Lamproderma echinosporum Meyl.. A. Sporocarps (note blackish brown depressed patches on the peridium surface and relatively long stalks). B. Capillitium, columella and peridium in transmitted light (note brown patches visible on the peridium). C. Spores in transmitted light (edge view). D. Spores in transmitted light (top view). E. Spore by SEM. F. Details of spore ornamentation by SEM. Bars:A = 1 mm, B = 500 μm, C–E = 10 μm, G = 3 μm. A: coll. DTK 3496, B: coll. DTK 8386, C–F: coll. DTK 6275.