Forty-five thermophilic streptomycetes were isolated from different habitats and examined for 163 unit characters with 8 representative thermophilic type strains, 29 reference strains and 16 randomly selected duplicated organisms for many phenotypic properties. The data were evaluated using the simple matching coefficients (SSM), and clustering achieved using the complete algorithm. It was clearly seen that the high cophenetic correlation, low test error values and high similarity level agreed with the defined numerical taxonomic criteria. The test strains were assigned to four aggregate groups consisting seven major (5-8 strains), nine minor (2-4 strains) and ten single membered clusters. It can be concluded that the numerical taxonomic studies yielded valuable information on the biodiversity of biotechnologically significant thermophilic streptomycetes from natural habitats.

Forty-five thermophilic streptomycetes were isolated from different habitats and examined for 163 unit characters with 8 representative thermophilic type strains, 29 reference strains and 16 randomly selected duplicated organisms for many phenotypic properties. The data were evaluated using the simple matching coefficients (SSM), and clustering achieved using the complete algorithm. It was clearly seen that the high cophenetic correlation, low test error values and high similarity level agreed with the defined numerical taxonomic criteria. The test strains were assigned to four aggregate groups consisting seven major (5-8 strains), nine minor (2-4 strains) and ten single membered clusters. It can be concluded that the numerical taxonomic studies yielded valuable information on the biodiversity of biotechnologically significant thermophilic streptomycetes from natural habitats.