Virgibacillus carmonensis sp nov., Virgibacillus necropolis sp nov and Virgibacillus picturae sp nov., three novel species isolated from deteriorated mural paintings, transfer of the species of the genus Salibacillus to Virgibacillus, as Virgibacillus marismortui comb. nov and Virgibacillus salexigens comb. nov., and emended description of the genus Virgibacillus