taxonID	type	description	language	source
FD1287E2FFDEFF93FF18F8E25960FDB9.taxon	description	Sporocarps scattered, stipitate, total height 1.62 – 1.86 mm. Sporotheca globose, 0.72 – 0.86 mm high, 0.78 – 0.96 diam. Hypothallus dark brown, shining, discoid. Stalk long, 1 / 2 to 4 / 7 of the total sporocarp height, 0.90 – 1.06 mm long, black, shining (Fig. 2 A). Peridium evanescent, observed only as a collar at sporotheca base (Fig. 2 A). Columella reaching about one-half of the sporotheca height, slightly tapering towards apex. Capillitium dense, black when spores are blown out, branching from columella at an acute angle, uniformly dark brown in transmitted light, threads rough, nodulose and spiny (Fig. 2 B). Spores colour in mass not observed, dark brown in transmitted light, slightly paler on one side, globose, 10.5 – 12 μm in total range, 11.23 ± 0.5 μm on average ± SD (n = 15), minutely warted (Figs 2 C – D).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFDEFF93FF18F8E25960FDB9.taxon	materials_examined	Material examined: — USA. Tehama Co.: Well’s Cabin Campground, 6300 ft, on dead wood, 12 June 1966, DTK 3391, together with Meriderma sp. (as L. atrosporum, UC 1408219!).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFDEFF93FF18F8E25960FDB9.taxon	discussion	Notes: — Comatricha nigricapillitia was unknown to Kowalski, since it was described in the genus Lamproderma later (Nannenga-Bremekamp 1989). Due to evanescent peridium it is similar to the species from the genus Meriderma (= Lamproderma atrosporum agg.) and therefore it was identified by Kowalski (1970 a) as L. atrosporum. The species is known from Europe (Poulain et al. 2011) and it has recently also been found in South America (Chile and Argentina) (Lado et al. 2013, Ronikier & Lado 2015) and in North America based on the revision of material identified as Comatricha suksdorfii (Moreno et al. 2004 b). All the collections revised by Moreno et al. (2004 b) originate from Colorado. The Kowalski’s collection reported here extends the North American species distribution to the West (California).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFDFFF94FF18F9BA5B4FFE08.taxon	materials_examined	Material examined: — USA. Crater Lake National Park, Park Headquarters, 6400 ft., on dead bark, 6 July 1967, DTK 6794, (as L. sauteri, UC 1408201!); Mt. Rainer National Park, 4 miles S of Cayuse Pass, 3500 ft., 9 June 1968, DTK 8356, (as L. sauteri, UC 1408280!). Notes: — Examined specimens of Diacheopsis kowalskii are typical in respect to all characteristic features (Meyer & Poulain 1998): bi-coloured reticulate capillitium composed of flattened threads, peridium surface covered with needle-like crystals, and spiny spores. Spores of examined specimens are covered with slender spines (Figs 3 F – G) and they are very similar to the spores of Lamproderma sauteri (Figs 19 F – G). Apparently Kowalski (1970 a) identified these collections (as L. sauteri) based mainly on spore ornamentation (see the chapter Discussion). Diacheopsis kowalskii is known from North America and Europe (Poulain et al. 2011).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFD9FF95FF18FC665901F7CD.taxon	materials_examined	Material examined: — USA. Tehama Co.: 3 miles E of Mineral, 5500 ft., on decaying twigs, 30 April 1966, DTK 2913 (as L. carestiae, UC 1408227!); Lassen Park, 6 miles S of Lassen Park, 5800 ft., on dead twigs, 27 April 1968, DTK 8286, together with Lamproderma echinosporum (as L. echinosporum, UC 1408254!); 2 miles S of Lassen Park, 6000 ft., on decayed wood, 21 May 1966, DTK 3060 (as L. carestiae, UC 1408210!); Butte Co.: 4 miles above Stirling City, 4000 ft., on dead wood, 27 May 1967, DTK 6247 (as L. carestiae, UC 1408245!); Siskiyou Co.: Mt. Shasta, 7200 ft., on dead wood, 4 July 1967, DTK 6682 (as L. carestiae, UC 1408270!); Shasta Co.: Lassen Park, Hat Lake, 6500 ft., on leaves, 1 July 1967, DTK 6510 (as L. carestiae, UC 1408242!); Crater Lake National Park, Garbage Dump, 6400 ft., on dead wood, 8 July 1967, DTK 6877 (as L. carestiae, UC 1408264!). Notes: — All specimens identified by Kowalski (1970 a) as L. arcyrioides turned out to be L. pulveratum (see comment to this species below), while all specimens identified by me as L. arcyrioides were identified by Kowalski (1970 a) as L. carestiae. Lamproderma carestiae was defined by Kowalski (1970 a) as a species with short stipe, dark brown capillitium, colourless only at the extremities, and densely spinulose, uniformly coloured spores 10 – 12 μm, while L. arcyrioides was defined as a species with distinctly pale capillitium tips and minutely warted spores 8 – 11 μm in diam. Interestingly, Kowalski (1970 a) believed that L. arcyrioides and L. carestiae frequently interbreed and that the separation of these two species is difficult. Apparently, L. caresiae ss. Kowalski (1970 a) is a scpecies complex including L. arcyrioides, L. ovoideum, L. sauteri var. atrogriseum and L. aff. ovoideum (Fig. 1). For further information, see comments under these species. Lamproderma arcyrioides occurs in Europe, North America and probably Asia (Poulain et al. 2011).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFDBFF98FF18F9AC5AA5FE2C.taxon	materials_examined	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 (1970 a) 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 (1970 a) specimens of that species were confirmed to be L. arcyrionema (Fig. 1). The species is cosmopolitan in distribution (Poulain et al. 2011).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFD5FF9AFF18FF465D69FE2C.taxon	materials_examined	Material examined: — USA. Butte Co.: 4 miles above Stirling City, 4000 ft., on bark, 9 May 1969, DTK 10016 (as L. fuscatum, UC 1408212!); Olympic National Park, Hurricane Ridge, 5200 ft., on twigs, 27 June 1968, DTK 9576 (as L. fuscatum, UC 1408234!); 24 June 1968, DTK 9361 (as L. fuscatum, UC 1408277!); Mount Rainier National Park, Bench Lake Trail, 4500 ft., on twig, 13 June 1968, DTK 8630 (as L. fuscatum, UC 1408271!). Notes: — Lamproderma argenteobrunneum is a very characteristic species with silvery, persistent peridium (Fig. 7 A), dense capillitium (Fig. 7 B) and rusty brown spores covered with spines fusing to form irregular short ridges (Figs 7 C – D, E – F). All specimens of L. argenteobrunneum were identified by Kowalski (1970 a) as L. fuscatum Meyl. Kowalski (1970 a) considered L. fuscatum to be the only Lamproderma species with uniformly rusty brown colour of peridium, capillitium and spores, a taxon easily recognized in the field. He studied Meylan’s collections of L. fuscatum and noticed differences in spore ornamentation — spinulose in the Europaean material and warted with slightly elongated warts in the United States material. He believed that these differences may show some genetic divergence between the two populations, but they are not large enough to warrant the separation of the two populations into different taxa. Kowalski (1970 a) in fact noticed one of the main differences between Lamproderma fuscatum (with evanescent peridium, currently classified within Meriderma) and L. argenteobrunneum (persistent peridium), but since he depreciated differences in peridium he could not recognize the two species as separate taxa. Among specimens identified by Kowalski (1970 a) as L. fuscatum there is also another species, L. kowalskii that has persistent peridium and warted spores (see comment to L. kowalskii below). For other comments see Ronikier et al. (2010). Lamproderma argenteobrunneum is known from North America and Europe (Ronikier et al. 2010, Poulain et al. 2011).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFD6FF9AFF18FDF15CCBF988.taxon	materials_examined	Material examined: — USA. Tehama Co.: Well’s Cabin Campground, 6300 ft., on decayed wood, 24 June 1967, DTK 6418 (as L. biasperosporum, UC 1408289!); Shasta Co.: Lassen Volcanic National Park, Near Summit Lake, 6700 ft., on decayed wood, 2 July 1967, DTK 6557 (as L. biasperosporum, UC 1408257!); Lassen Volcanic National Park, King’s Creek, 7200 ft., on dead wood, 27 July 1967, DTK 7531 (as L. biasperosporum, UC 1408288!); Siskiyou Co.: Mt. Shasta, 7600 ft., on dead wood, 24 July 1967, DTK 7312 (as L. biasperosporum, UC 1408295!); DTK 7311 (as L. biasperosporum, UC 1407698!); DTK 7310 (as L. biasperosporum, UC 1408249!); DTK 7356, together with Enerthenema sp. (as L. biasperosporum, UC 1408290!); 25 July 1967, DTK 7442 (as L. biasperosporum, UC 1408292!); Crater Lake National Park, Cleetwood, 7000 ft., on decayed wood, 7 July 1967, DTK 6854, together with Cribraria sp. (as L. biasperosporum, UC 1408293!). Notes: — Lamproderma biasperosporum is simillar to L. arcyrionema, but clearly differs from the latter by sporocarp size (sporotheca less than 0.5 mm in diam.; Figs 8 A – B), capillitium colour that is white when spores are blown out (Fig. 8 B) and the type of capillitium that branches radially from the top of the columella (Fig. 8 C). For more detailed comparison of these two species, see Kowalski (1968, 1970 a). The substrate noted by Kowalski (1968, 1970 a) for L. biasperosporum was decaying coniferous wood. According to my observation the species occurs on dead wood and more often on basidiomes of various corticioid fungi. All specimens of L. biasperosporum were confiremd to be this species (Fig. 1). The species occurs in North America, Africa and Asia (Poulain et al. 2011).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFD6FF9BFF18F95D5B30FE2C.taxon	materials_examined	Material examined: — USA. Mendocino Co.: MacKerricher Beach State Park, on decayed wood [covered with mosses], 25 January 1967, DTK 4826 (as L. columbinum, UC 1408267!), DTK 4824 (as L. columbinum, UC 1408223!); 7 April 1968, DTK 8055 (as L. columbinum, UC 1408228!); on bark [covered with mosses], 8 April 1968, DTK 8087 (as L. columbinum, UC 1408222!). Notes: — Lamproderma columbinum is very characteristic species due to the long but massive stalk, small sporotheca and thick columella. All specimens identified by Kowalski (1970 a) as L. columbinum were confirmed to be this species. The species is cosmopolitan (Poulain et al. 2011).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFD0FF9DFF18F98358A4FE64.taxon	materials_examined	Material examined: — USA. Tehama Co.: 5 miles of Child’s Meadows, 5100 ft, on dead wood, 30 April 1966, DTK 2863 (as L. disseminatum, UC 1408216!); 3 miles of Child’s Meadows, 5200 ft, on dead wood, 20 May 1967, DTK 6211 Type (as L. disseminatum, UC 1408238!). Notes: — Lamproderma disseminatum is a very characteristic species due to the unique pattern on the inner peridium surface (Fig. 10 C). Silvery sporothecae, dark and rough capillitium and bi-coloured spores covered with warts with wartlets when observed by SEM are also distinctive characters. All specimens identified by Kowalski (1970 a) were confirmed to be L. disseminatum. The species is known from North America and Europe (Poulain et al. 2011).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFD1FF9FFF18F85C5965FDB9.taxon	materials_examined	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 (1970 b). All specimens identified by Kowalski (1970 a) as L. echinosporum were confirmed to be this species. Interestingly, North American specimens are characterised by long stalk (Fig. 11 A) 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).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFD3FF9FFF18FD4D5B6DFB78.taxon	materials_examined	Material examined: — USA. Tehama Co.: Well’s Cabin Camp ground, 6300 ft., on twigs, 24 June 1967, DTK 6408 (as L. fuscatum, UC 1408233!, holotype); Tehama Co.: 3 miles W of Child’s Meadow, 5200 ft., on dead wood, 20 May 1967, DTK 6169 (as L. fuscatum, UC 1408279!); 3 miles E of Mineral, on decayed wood, DTK 6161 (as L. fuscatum UC 1408235!); 1 mile S of Lassen National Park, on dead twigs, 28 May 1966, DTK 3173 (as L. fuscatum, UC 1408269!); Siskiyou Co.: Mt. Shasta, 7600 ft., on dead twigs, DTK 7453 (as L. fuscatum, UC 1408275!). Notes: — Lamproderma kowalskii is very similar to L. argenteobrunneum from which it differs in spore ornamentation (Fig. 12 C – F), and to Meriderma fuscatum (Meyl.) Mar. Mey. & Poulain from which it can be distinguished by persistent peridium (Fig. 12 A). All three species share similar, rusty brown colours of spores in mass and capillitium. Depreciating peridium characters, Kowalski (1970 a) classified all rusty brown specimens as one species Lamproderma fuscatum (see comments to L. argenteobrunneum). For further comments see Ronikier et al. (2010). Lamprorderma kowalskii is known from North America (Ronikier et al. 2010, Poulain et al. 2011), and it has recently been reported from Europe (Erastova et al. 2017).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFD3FF80FF18FB0D5ACAFE09.taxon	materials_examined	Material examined: — USA. Tehama Co.: 3 miles W, of Child’s Meadows, 5200 ft., on bark, 20 May 1967, DTK 6200, (as L. maculatum, UC 1408239!, type); 3 miles E of Mineral, 5000 ft., on dead twig, 20 May 1967, DTK 6100 (as L. maculatum, UC 1408203!); Well’s Cabin Campground, 6300 ft., on dead twigs, 18 June 1966, DTK 3470, together with Meriderma sp. (as L. sauteri, UC 1408286!); Butte Co.: 4 miles E of Inskip, 5500 ft., on decayed twig, 23 April 1966, DTK 2813 (as L. maculatum, UC 1408205!); Siskiyou Co.: Mt. Shasta, 7600 ft., on dead twig, 25 July 1967, DTK 7396 (as L. maculatum, UC 1408215!); Mt. Rainer National Park, Bench Lake Trail, 4500 ft., on twigs, 13 June 1968, DTK 8664 (as L. maculatum, UC 1408214!); Shasta Co.: Lassen Volcanic National Park, near Summit Lake, 6700 ft., on twigs, 2 July 1967, DTK 6551, together with Meriderma sp. (as L. atrosporum, UC 1408251!). Notes: — All studied specimens matched well Kowalski’s (1970 a) description and they were confirmed to be L. maculatum. The species is characterized by peridium with brown, depressed patches (Figs 13 A, C) and large, dark brown, densely warted spores (Figs 13 D – G). Additionally, one collection of L. sauteri was found to represent L. maculatum, but it seems to be rather an oversight or a mistake than a result of differences in original treatment of L. maculatum by Kowalski (1970 a), since he describes in detail the characters distinguishing the two species (Kowalski 1970 a). Lamproderma maculatum is the most similar to L. pseudomaculatum Mar. Mey. & Poulain that differs in more delicate and paler capillitium and slightly smaller spores (Poulain et al. 2011). Lamproderma maculatum is known from Europe, North America, Asia, South America and Australia (Stephenson et al. 2007 b, Stephenson & Shadwick 2009, Poulain et al. 2011, Ronikier & Lado 2015).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFCDFF82FF18F9AE5C0AFD5C.taxon	materials_examined	Material examined: — USA. Tehama Co.: 3 miles E of Mineral, 5000 ft., on duff, 20 May 1967, DTK 6147 (as L. sauteri, UC 1408237!); 3 miles W of Child’s Meadows, 5200 ft., on bark, 20 May 1967, DTK 6223 (as L. sauteri, UC 1408283!). Notes: — Lamproderma ovoideoechinulatum is a recently described species (Poulain & Meyer 2005) that was not known to Kowalski (1970 a), who apparently treated L. sauteri in a wider sense including specimens with ovoid sporothecae. Two of the specimens identified by Kowalski (1970 a) as L. sauteri have clearly ovoid sporothecae with dark capillitium originating from the greater part of the columella (Fig. 14 D) — the character of L. ovoideoechinulatum. Since L. sauteri and L. ovoideum have similar spores (Figs 14 E – H, 19 D – G), Kowalski (1970 a) who depreciated sporotheca shape and overestimated spore characteristics could not tell these two morphotypes apart. Lamproderma ovoideoechinulatum is known from Europe, North America and Asia (Poulain et al. 2011).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFCFFF84FF18FF4558A5FE2D.taxon	materials_examined	Material examined: — USA. Mt. Rainer Nat. Park, Bench Lake Trail, 4500 ft., on twigs, 10 June 1968, DTK 8401 (as L. carestiae, UC 1408273!). Notes: — Kowalski (1970 a) did not recognize L. ovoideum as a separate taxon, but considered it to be conspecific with L. sauteri. Interestingly, however, none of the revised specimens of L. sauteri turned out to be L. ovoideum. Only one specimen of typical L. ovoideum was found in the examined material and this collection was originally identified as L. carestiae. Lamproderma carestiae was considered by Kowalski (1970 a) as including L. ovoideum var. cucumer Meyl., currently treated at a species level as L. cucumer (Meyl.) Nowotny & H. Neubert. Lamproderma ovoideum occurs in Europe, North and South Americas, Asia, Australia and New Zealand (Stephenson et al. 1992, Stephenson & Johnston 2003, Stephenson et al. 2007 a, b, Stephenson & Shadwick 2009, Poulain et al. 2011, Ronikier & Lado 2015).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFC8FF84FF18FDF15A0AFA50.taxon	materials_examined	Material examined: — USA. Tehama Co.: 3 miles W of Child’s Meadows, 5200 ft., on dead twigs and duff, 20 May 1967, DTK 6237 (as L. carestiae, UC 1408244!); Well’s Cabin Campground, 6300 ft., on dead twigs, 24 June 1967, DTK 6361 (as L. carestiae, UC 1408246!). Notes: — The two examined specimens seem to be intermediate between L. ovoideum and L. ovoideoechinulatum var. microsporum Mar. Mey. & Poulain. They differ from the first by smaller spores and by blue, violet and green reflections dominating in the peridium, that are persisting in detached parts of the peridium. From the latter they differ by less delicate capillitium and spore ornamentation that is in the form of warts, not spines. This morphotype has also larger dimensions of sporocarps (total heigth) and longer stalk than the two other species. More material is needed to unequivocally identify these two collections.	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFC8FF86FF18FA755BD6FE41.taxon	materials_examined	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 17 F – 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. 17 C). Lamproderma pulveratum occurs in Europe and Asia (Poulain et al. 2011) and it has recently been reported from the Southern Hemisphere (Ronikier & Lado 2015).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFCAFF88FF18F8B85D6CFE2C.taxon	materials_examined	Material examined: — USA. Olympic National Park, Hurricane Ridge, 5200 ft., on dead twig, 14 July 1967, DTK 7072 (as L. cribrarioides, UC 1408206!); on twigs, 25 June 1968, DTK 9446 (as L. cribrarioides, UC 1408202!). Notes: — The name Lamproderma retirugisporum was proposed for L. cribrarioides after discovery that its type collection is a taxon with evanescent peridium, currently classified within the genus Meriderma (M. cribrarioides) (Singer et al. 2003 b), not a taxon with persistent peridium as interpreted by most authors (Martin & Alexopoulos 1969, Neubert et al. 2000). Kowalski (1970 a) interpreted L. cribrarioides as a species with evanescent peridium, in its original sense, but since he considered peridium differences not meaningful and based species identification mostly on spore characteristics he apparently was not able to distinguish the two taxons that have almost identical spores (Figs 18 D – G, 22 D – G). Examined Kowalski’s collections of L. cribrarioides are either L. retirugisporum or Meriderma cribrarioides (see below). Lamproderma retirugisporum is a cosmopolitan species (Poulain et al. 2011).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFC4FF88FF18FDF85C0BFAA3.taxon	materials_examined	Material examined: — USA. Olympic National Park, Hurricane Ridge, 5200 ft., on living twigs, 14 July 1967, DTK 7073 (as L. sauteri, UC 1408259!); DTK 7094 (as L. sauteri, UC 1408248!); DTK 7145 (as L. sauteri, UC 1408225!); DTK 7116 (as L. carestiae, UC 1408247!); Olympic National Park, 2 mi. below Hurricane Ridge, 4800 ft., on twigs, 22 June 1968, DTK 9177 (as L. sauteri, UC 1408285!). Notes: — Kowalski (1970 a) treated L. sauteri in a wider sense, including L. ovoideum. In the studied material, five of ten specimens identified by Kowalski (1970 a) as L. sauteri have been confirmed. However, all of them had grey peridium only slightly iridescent — a character of var. atrogriseum and none of the examined specimens represented typical variety. Lamproderma sauteri is a cosmopolitan myxomycete (Poulain et al. 2011).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFC4FF8AFF18FA415CC6FE98.taxon	materials_examined	Material examined: — USA. Butte Co.: Lower Bidwell Park, Chice, on decayed bark, 10 December 1966, DTK 4173 (as L. scintillans, UC 1408243!); Butte Creek & Skyway, on decayed twigs, 16 December 1966, DTK 4223 (as L. scintillans, UC 1408241!); U. S. 99 & Butte Creek, on plant debris, 9 December 1966, DTK 4093, together with Diacheopsis sp. (as L. scintillans, UC 1408231!); Glenn Co.: 13 miles S. of Hamilton City, on decayed wood, 29 December 1966, DTK 4519 (as L. scintillans, UC 1408265!); on decayed bark, 14 January 1967, DTK 4777 (as L. scintillans, UC 1408261!); DTK 4731, together with Comatricha sp. and Didymium sp. (as L. scintillans, UC 1408209!); Marin Co.: Tomales Bay State Park, on plant debris, 28 January 1967, DTK 5020 (as L. scintillans, UC 1408260!); Tehama Co.: Woodson Bridge State Park, on decayed leaves, 11 February 1967, DTK 5361, together with Badhamia sp. and Didymium sp. (as L. scintillans, UC 1408240!). Notes: — Lamproderma scintillans is interpreted by Kowalski (1970 a) in its present sense: as non-nivicolous species with capillitial threads much paler, often hyaline near the columella and brown at some distance from the columella (Fig. 20 D), and with spores covered with perfectly regularly distributed broadly conical, dark brown spines (Figs 20 E – H). The species is usually long-stalked (e. g. Poulain et al. 2011), but in the Kowalski’s material I found it to be variable, from short stalked (3 / 8 of the total sporocarp height; from 0.26 mm) to long stalked (2 / 3 of the total sporocarp height; up to 0.96 mm). All specimens identified as L. scintillans by Kowalski (1970 a) was confirmed to belong to this species. Due to the characteristic spore ornamentation and bi-coloured capillitium it is one of the most easily identified species from the genus. It is cosmopolitan in distribution (Poulain et al. 2011).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFC6FF8CFF18F8C558A5FC01.taxon	description	Sporocarps scattered or in loose groups, stipitate, total height 1.44 – 2.34 mm (Fig. 21 A). Sporotheca broadly ovoid to globose, with rounded or broadly conical base, 0.70 – 1.36 mm high, 0.64 – 1.10 mm diam (Figs 20 A – B). Hypothallus, thick, red brown, continuous and connecting many sporocarps. Stalk about one-half (3 / 7 to 1 / 2) of the total sporocarp height, 0.74 – 1.10 mm long, black, tapering upwards, sometimes laterally flattened, often with a membranous hypothallus remnants attached at one side (Figs 21 A – B). Peridium evanescent, dehiscing in small patches, remaining only at the base of the sporotheca, black, iridescent, with silver and golden reflections under reflected light, pale brown, smooth and transparent in transmitted light (Figs 21 A – B). Columella reaching about one-half of the sporotheca height, cylindrical to clavate (Fig. 21 B). Capillitium moderately dense, black when spores are blown out, dark brown in transmitted light, with few to many anastomoses in peripheral part and with funnel-shaped ends (Figs 20 B – C). Spores black in mass, dark brown in transmitted light, slightly paler at one side, globose, (12) 12.5 – 13.5 (15.5) μm in total range, 13.13 ± 0.7 μm on average ± SD (n = 30), covered with connected spines forming branched ridges with or without closed meshes, and with some free spines (Figs 21 D – G), ornamentation up to 1 μm high, composed of fused spines that form incomplete or complete, dense reticulum with perforated muri by SEM (Figs 21 H – K).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFC6FF8CFF18F8C558A5FC01.taxon	materials_examined	Material examined: — USA. Tehama Co.: 3 miles E of Mineral, 5800 ft., on decaying wood, 15 May 1966, DTK 2937 (as L. atrosporum, UC 1408268!); 3 miles E of Mineral, 5000 ft., on dead wood, 20 May 1967, DTK 6110 (as L. atrosporum, UC 1408220!).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFC6FF8CFF18F8C558A5FC01.taxon	discussion	Notes: — Kowalski designated lectotype of L. atrosporum (Kowalski 1975 a) circumscribing the species boundaries as a taxon with funnel-shaped capillitium tips and variable spore ornamentation from spinulose to reticulate, but never banded-reticulate. Two of the Kowalski’s (1970 a) specimens of L. atrosporum have spores ornamented with fused spines that form incomplete or complete, dense reticulum and thus belong to L. carestiae (see Poulain et al. 2003), currently classified within the genus Meriderma (Poulain et al. 2011). The two examined collections differ slightly in spore ornamentation. Spores of DTK 2937 are covered with connected spines forming ridges without closed meshes (Figs 21 D – E, H – I), so could be referred to the typical morphotype (Meriderma carestiae var. carestiae, see Poulain et al. 2011), while the spores of DTK 6110 are covered with spines connected by ridges and forming many closed meshes or dense net-like patterns (Figs 21 F – G, J – K). The latter collection may be classified as the undescribed morphotype ‘ Meriderma carestiae var. retisporum’ (Poulain et al. 2011). Meriderma carestiae is known from the Northern Hemisphere (Poulain et al. 2011) and it has recently been reported from South America (Ronikier & Lado 2015).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
FD1287E2FFC0FF8CFF18FC255CB0F810.taxon	materials_examined	Material examined: — USA. Tehama Co: 3 miles E of Mineral, 5000 ft., on dead twig, 20 May 1967, DTK 6105 (as L. cribrarioides, UC 1408204!); 5 miles W of Child’s Meadow, 5100 ft., 30 April 1966, DTK 2878, together with Lamproderma sp. (as L. cribrarioides, UC 1408224!); 6 miles S of Lassen Park, 5800 ft., on dead twigs, 27 April 1968, DTK 8285 (as L. cribrarioides, UC 1408207!); Siskiyou Co.: Mt. Shasta, 7600 ft., on dead twigs, 25 July 1967, DTK 7450 (as L. cribrarioides, UC 1408200!); Whatcom Co.: 16 miles E of Glacier, 4000 ft., on twigs, 20 June 1968, DTK 9077 (as L. cribrarioides, UC 1408217!); 15 June 1968, DTK 8779 (as L. cribrarioides, UC 1408218!); Lassen Park, near Summit Lake, 7000 ft., on dead twig, 26 July 1967, DTK 7484 (as L. cribrarioides, UC 1408208!); Mt. Rainer National Park, Bench Lake Trail, 4300 ft., on twigs, 10 June 1968, DTK 8413 (as L. cribrarioides, UC 1408229!); Notes: — Most revised Kowalski’s (1970 a) specimens of L. cribrarioides were confirmed to be this species, currently included in the genus Meriderma (Poulain et al. 2011). For further notes see comments at L. retirugisporum. Perforations in spore reticulation have been observed in all spores examined under SEM, also in those with the most regular and highest reticulation. Meriderma cribrarioides occurs in Europe (Poulain et al. 2011).	en	Ronikier, Anna (2022): Revision of the Donald T. Kowalski’s collections of Lamproderma (Myxomycetes, Amoebozoa) reveals twice higher species diversity. Phytotaxa 531 (3): 175-210, DOI: 10.11646/phytotaxa.531.3.2
