Modest proposals to expand the type material for naming of prokaryotes.

Gene sequences are herein proposed to be suitable type material for the description of prokaryotic species. This proposal follows from the principles described in the International Code of Nomenclature of Prokaryotes. This simple change in the Code will allow for the stability of naming of Candidatus taxa, endosymbionts and uncultivated prokaryotes and will meet an important need within microbiology. In addition, modern molecular techniques allow the identification of genera even when the species remain obscure. The Code should be modified to allow gene sequences to serve as the type material for genera in the absence of described species. This simple change will unite the nomenclature of the cultured and uncultured prokaryotes into a single, robust system.