A numerical taxonomic study has been carried out to establish the relationship of group F to other biochemically similar organisms within the family Vibrionaceae. A total of 154 strains were examined including 59 of group F. Out of 114 characters determined for each strain 100 were used to compute average Euclidean distances between strains. Four methods of clustering were used, all of which gave very similar results.
Strains resembling
Vibrio anguillarum
fell into clusters corresponding to
V. anguillarum, Beneckea nereida
and a previously unrecognized group, phenon 5. Strains of the
Aeromonas hydrophila/punctata
group formed a heterogenous phenon within which certain subdivisions, perhaps artificial, could be discerned.
Group F strains all fell in one closely‐knit cluster distinct from all the species of
Vibrio, Aeromonas, Plesiomonas
and
Photobacteriwn
studied. Group F strains could be divided into two biovars, I and II. Both biovars are present in aquatic, particularly estuarine, environments throughout the world but biovar I strains have also been isolated from humans with diarrhoea. It is concluded that group F is a synonym of group EF6 and that the strains within these groups should be classified in a new species named
Vibrio fluvialis.
The type strain is NCTC 11327.