Lamproderma pulveratum Mar. Mey. & Poulain, 1991

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 : 195-197

Lamproderma pulveratum Mar. Mey. & Poulain , in Bozonnet et al. (1991: 54). Fig. 17

Sporocarps in loose or dense groups, stipitate, total height (0.96)1.48–1.86(2.26) mm( Fig. 17A ).Sporotheca subglobose, almost always wider than high, with a strongly flattened base, (0.60)0.82–1.28(1.50) mm high, (0.84)0.90–1.32(1.50) mm diam. Hypothallus red brown, discoid or continuous under several sporocarps. Stalk short, 2/7 to 1/2 of the total sporocarp height, 0.36–0.76(0.88) mm long, black, shining ( Fig. 17B ). Peridium persistent, dehiscing in large patches, surface rough and covered with short (more rarely needle-like) crystals, with blue, violet and golden reflections also when spores are blown out ( Fig. 17A ), pale brown in transmitted light and rough from brownish pigment. Columella reaching about one-half of the sporotheca height, cylindrical to narrowly conical ( Fig. 17B ). Capillitium originating from the greater part of the columella, radiating, moderately dense, brown with white extremities when spores are blown out, rusty brown in transmitted light, with scattered brown nodes and also scattered nodes filled with crystals ( Figs 17B–C ), with many anastomoses especially in peripheral part, extremities paler, usually incrusted with pigment. Spores in mass dark brown to blackish brown, very pale brown in transmitted light, uniformly coloured, with a tiny, paler germ pore at one side, globose (8.5)9–11.5(12) μm in total range, 10.28 ±0.8 μm on average ±SD (n = 330), covered with loosely arranged thick (wide) warts ( Figs 17D–E ), baculate by SEM, baculae short and wide ( Figs 17F–G ).

Material examined:— USA. Tehama Co.: Well’s Cabin Campground, 6300 ft., on dead twigs, 18 June 1966, DTK 3496, together with L. echinosporum (as L. echinosporum, UC 1408226!); 24 June 1967, DTK 6350 (as L. arcyrioides, UC 1408287!); 5 miles E. of Mineral, 5800 ft., on duff, 15 May 1966, DTK 2966 (as L. arcyrioides, UC 1408262!); 2 miles S. of Lassen Park, 6000 ft., 21 May 1966, DTK 3035 (as L. arycrioides, UC 1408256!); Shasta Co.: Lassen Park, near Summit Lake, 6700 ft., on duff, 2 July 1967, DTK 6602 (as L. arcyrioides, UC 1408250!); Lassen Park, King’s Creek, 7200 ft., on dead twigs, 27 July 1967, DTK 7524 (as L. arcyrioides, UC 1408291!); Siskiyou Co.: Mt. Shasta, 7200 ft., on dead twigs, 4 July 1967, DTK 6653 (as L. arcyrioides, UC 1408281!); Mt. Shasta, Panther’s Meadows Campground, 7600 ft., on twigs, 6 July 1965, DTK 1858 (as L. arcyrioides, UC 1408294!); Crater Lake National Park, Park Headqurters, 6400 ft., on dead twigs, 6 July 1967, DTK 6750 (as L. arcyrioides, UC 1408284!); Olympic National Park, Hurricane Ridge, 5200 ft., on live twigs, 15 July 1967, DTK 7216 (as L. arcyrioides, UC 1408282!); DTK 7243 (as L. arcyrioides, UC 1408255!).

Notes:— Lamproderma pulveratum was segregated from the L. arcyrioides species complex in more than 20 years after Kowalski collected it in the field ( Bozonnet et al. 1991). Indeed, all specimens identified by Kowalski as L. arcyrioides represent L. pulveratum . The latter differs from the former by wider and more loosely arranged warts on spores ( Figs 17F–G ), by the tendency to form aggregated colonies of sporocarps and rough peridium covered with usually tiny, short (not needle-like) crystals. All North American specimens had also crystals present in nodes of capillitium ( Fig. 17C ). Lamproderma pulveratum occurs in Europe and Asia ( Poulain et al. 2011) and it has recently been reported from the Southern Hemisphere ( Ronikier & Lado 2015).

Figures

FIGURE 17. Lamproderma pulveratum Mar. Mey. et Poulain A. Sporocarps (note short crystals on peridium surface). B. Open sporocarp (note rusty brown capillitium). C. Nodes of capillitium (note crystals inside). D. Spores in transmitted light (edge view). E. Spores in transmitted light (top view). F. Spore by SEM. G. Details of spore ornamentation by SEM. Bars: A–B = 1 mm, C –F = 10 μm, G = 3 μm. A: coll. DTK 2966, B: coll. DTK 6653, C: coll. DTK 7524, D–E: coll. DTK 6350, F–G: coll. DTK 7216.