PROPOSED MINIMAL STANDARDS FOR DESCRIPTION OF NEW TAXA IN THE ORDER HALOBACTERIALES

In accordance with Recommendation 30b of the International Code of Nom enclature of Bacteria, which calls for the development of minimal stan dards for describing new species, we propose minimal standards for des cription of new taxa in the order Halobacteriales. The minimal standar ds include information on the following characteristics: cell morpholo gy; motility; pigmentation; the requirement for salt to prevent cell l ysis; optimum NaCl and MgCl, concentrations for growth and range of sa lt concentrations enabling growth; temperature and pH ranges for growt h; anaerobic growth in the presence of nitrate or arginine; acid produ ction from a range of carbohydrates; ability to grow on single carbon sources; catalase and oxidase tests; hydrolysis of starch, casein, and Tween 80; sensitivity to different antibiotics; and polar lipids. The placement of a new taxon should be consistent with phylogeny, which i s usually based on 16S rRNA nucleotide sequence information, and with DNA-DNA hybridization data in the case of descriptions of new species. This proposal has been endorsed by the members of the Subcommittee on the Taxonomy of Halobacteriaceae of the International Committee on Sy stematic Bacteriology.