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British records
Tran s. Br, mycol. Soc. 51 (3 and 4),587-588 (1968) Printed in Great Britain
BRITISH RECORDS 95. Myriococcum albomyces Cooney & Emerson (Thermophilic fungi, pp. 51-61, 1964) was collected from: (a) grass compost at Keele, Staffs., Jan. 1967, IMI 125815; (b) sand dune litter at Borth, Cardigans., Feb. 1967; (c) animal and plant manure at Dovedale, Derbys., June 1967; (d) Betula litter at Silverdale, Staffs., June ]967; (e) Calluna vulgaris litter at Liathach, Loch Torridon, Wester Ross, July ]967; (f) pond mud at Keele, Staffs., Aug. ]967. This thermophilic fungus has been isolated twice in N. America from nesting materials of domestic chickens, but has not been reported since. The six strains of M. albomyces all grow vigorously on sterilized grass and straw cuttings, unlike the strain reported by Cooney & Emerson (1964). Growth is less vigorous on a cellulose agar medium, where celllllm;p. i:-:. the form of Whatman Chromedia cellulose powder, is the only carbon source present. On potato dextrose agar growth is slow and mature ascocarps never develop, but on yeast-starch agar growth is rapid, resulting in a dense white mat. Ascocarps become noticeable after about 10 days and when mature are brown to black, spherical, 10~250 p. diam. In some strains ascocarps develop in profusion but only to a limited extent in others. Only one fertile ascocarp has been observed, the ascospores being light brown, spherical and 10 p. diam. The prostrate and submerged hyphae form spore-like bodies, usually in chains, of diverse shape and size. These cells develop thick walls and stain heavily with cotton blue in lactophenol. They have been observed to germinate by germ-tubes, functioning in this manner as asexual spores. Due to the scarcity of fertile ascocarps it is thought that the spread of the species depends mainly on these specialized hyphal cells. Cooney & Emerson conclude that M. albomyces is unlikely to be widespread in occurrence, but my findings suggest a fairly wide geographical distribution on a variety of substrates. The strains isolated from Betula, Calluna vulgaris and sand dune litter have temperature ranges (24- 58 °C ) similar to the strains isolated from composting material, although the latter substrate had a very much higher temperature. The strain isolated from C. vulgaris litter was collected approximately 1500 ft (457'2m) above sea level, where temperatures can rarely be expected to support a thermophilic type ofgrowth. The soil temperature at the time of sampling was 16°, well below the minimum for growth of this fungus. M. albomyces must, in this case, have an ephemeral life-cycle, growing during periods of abnormally high soil temperatures and surviving during unfavourable conditions in the form of thick-walled hyphal cells or depend entirely on its sexuai :si.al:>C [VI survival. 96. Torula thermophila Cooney & Emerson (Thermophilicfungi, pp. 88-g2, 1964) was collected from: (a) grass compost at Keele, Staffs., Jan. 1967 IMI ]25821; (b) cow dung at Keele, Staffs., Mar. 1967; (c) animal and plant
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Transactions British Mycological Society
manure at Dovedale, Derbys., June 1967; (d) mushroom compost at Keele, Staffs., Nov. 1967. The substrates were all undergoing decomposition and temperatures ranged from 30 to 60°. T. thermophile has been isolated several times in N. America but has not been reported in this country. The cultural characteristics on yeaststarch agar (YpSs) agree well with those described by Cooney & Emerson. On potato dextrose agar growth is rapid at 40° and usually takes the form of chains of dark brown arthrospores ramifying through and on the surface of the agar. Areas of dense mycelium and spore formation occur, giving the colony a zoned appearance, a constant cultural feature on this medium. The arthrospores are spherical, dark brown with thick walls and arc produced in single or branched chains. Cooney & Emerson gave measurements of 8-12'5,u (occasionally 17,u) for spore diameter. However, the spores of the present four isolates are consistently larger, the average diameter being about 14,u and the range 9-18,u. Cultures of both species have been deposited at the Commonwealth Mycological Institute, Kew. REFERENCE COONEY,
D. G. &
EMERSON,
R. (1964). Thermophilic fungi. San Francisco: Freeman.
H. C. EVANS,
Department of Biology, The University, Keele
BRITISH RECORDS 95. Myriococcum albomyces Cooney & Emerson (Thermophilic fungi, pp. 51-61, 1964) was collected from: (a) grass compost at Keele, Staffs., Jan. 1967, IMI 125815; (b) sand dune litter at Borth, Cardigans., Feb. 1967; (c) animal and plant manure at Dovedale, Derbys., June 1967; (d) Betula litter at Silverdale, Staffs., June ]967; (e) Calluna vulgaris litter at Liathach, Loch Torridon, Wester Ross, July ]967; (f) pond mud at Keele, Staffs., Aug. ]967. This thermophilic fungus has been isolated twice in N. America from nesting materials of domestic chickens, but has not been reported since. The six strains of M. albomyces all grow vigorously on sterilized grass and straw cuttings, unlike the strain reported by Cooney & Emerson (1964). Growth is less vigorous on a cellulose agar medium, where celllllm;p. i:-:. the form of Whatman Chromedia cellulose powder, is the only carbon source present. On potato dextrose agar growth is slow and mature ascocarps never develop, but on yeast-starch agar growth is rapid, resulting in a dense white mat. Ascocarps become noticeable after about 10 days and when mature are brown to black, spherical, 10~250 p. diam. In some strains ascocarps develop in profusion but only to a limited extent in others. Only one fertile ascocarp has been observed, the ascospores being light brown, spherical and 10 p. diam. The prostrate and submerged hyphae form spore-like bodies, usually in chains, of diverse shape and size. These cells develop thick walls and stain heavily with cotton blue in lactophenol. They have been observed to germinate by germ-tubes, functioning in this manner as asexual spores. Due to the scarcity of fertile ascocarps it is thought that the spread of the species depends mainly on these specialized hyphal cells. Cooney & Emerson conclude that M. albomyces is unlikely to be widespread in occurrence, but my findings suggest a fairly wide geographical distribution on a variety of substrates. The strains isolated from Betula, Calluna vulgaris and sand dune litter have temperature ranges (24- 58 °C ) similar to the strains isolated from composting material, although the latter substrate had a very much higher temperature. The strain isolated from C. vulgaris litter was collected approximately 1500 ft (457'2m) above sea level, where temperatures can rarely be expected to support a thermophilic type ofgrowth. The soil temperature at the time of sampling was 16°, well below the minimum for growth of this fungus. M. albomyces must, in this case, have an ephemeral life-cycle, growing during periods of abnormally high soil temperatures and surviving during unfavourable conditions in the form of thick-walled hyphal cells or depend entirely on its sexuai :si.al:>C [VI survival. 96. Torula thermophila Cooney & Emerson (Thermophilicfungi, pp. 88-g2, 1964) was collected from: (a) grass compost at Keele, Staffs., Jan. 1967 IMI ]25821; (b) cow dung at Keele, Staffs., Mar. 1967; (c) animal and plant
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Transactions British Mycological Society
manure at Dovedale, Derbys., June 1967; (d) mushroom compost at Keele, Staffs., Nov. 1967. The substrates were all undergoing decomposition and temperatures ranged from 30 to 60°. T. thermophile has been isolated several times in N. America but has not been reported in this country. The cultural characteristics on yeaststarch agar (YpSs) agree well with those described by Cooney & Emerson. On potato dextrose agar growth is rapid at 40° and usually takes the form of chains of dark brown arthrospores ramifying through and on the surface of the agar. Areas of dense mycelium and spore formation occur, giving the colony a zoned appearance, a constant cultural feature on this medium. The arthrospores are spherical, dark brown with thick walls and arc produced in single or branched chains. Cooney & Emerson gave measurements of 8-12'5,u (occasionally 17,u) for spore diameter. However, the spores of the present four isolates are consistently larger, the average diameter being about 14,u and the range 9-18,u. Cultures of both species have been deposited at the Commonwealth Mycological Institute, Kew. REFERENCE COONEY,
D. G. &
EMERSON,
R. (1964). Thermophilic fungi. San Francisco: Freeman.
H. C. EVANS,
Department of Biology, The University, Keele