Characterization of some previously unclassified "Pasteurella" spp. obtained from the oral cavity of dogs and cats and description of a new species tentatively classified with the family Pasteurellaceae Pohl 1981 and provisionally called taxon 16.

The taxonomic relationship of 23 unclassified canine and feline strains of Pasteurellaceae and five strains received as Pasteurella spp. or Haemophilus influenzae-murium was investigated by phenotypic and genetic characterization. Eleven strains were classified with four recently described species of genus Pasteurella sensu stricto. Fourteen canine and feline strains formed a homogeneous group, tentatively designated taxon 16. Both phenotypic characters and mol% G + C in DNA and genome size indicate classification of taxon 16 with genus Pasteurella. DNA/DNA hybridizations, however, failed to locate taxon 16 on genus level with accepted or proposed species of the family Pasteurellaceae Pohl 1981. Two additional species obtained from rats and mice remained unclassified, in addition to a human isolate obtained from a dog-bite. The necessity of detailed phenotypic characterization within the family Pasteurellaceae Pohl 1981 needs to be stressed.