The comparison of the Saccharomonospora phages phi SaC1, phi SaG1, phi SaV1, phi SaV2, phi SaV3, and Tm1 demonstrated that they all belong to a single group of closely related actinophages: they were similar with regard to host range, virion mophology (B1 type), genome length (43-45 kb), and GC content of their genomes (63, 3% G + C). Furthermore, DNA-DNA hybridization showed that the phage genomes had a high degree of homology to each other. The phages are, therefore, proposed as representatives of a new bacteriophage species in the sense of the ICTV.