Two anaerobic, non-spore-forming, pleomorphic, Gram-negative rods, designated 
YIT 11840T and YIT 11841T, were isolated from human faeces. The organisms were 
catalase-negative, produced succinic and acetic acids as end products of glucose 
metabolism and had DNA G+C contents of approximately 48-49 mol%. Although the 
phenotypic characteristics of these two strains were very similar, analysis of 
their 16S rRNA gene sequences showed that they are only distantly related 
(93.8%), indicating that they represent two different species. A comparative 
sequence analysis revealed that these two species are members of the family 
'Prevotellaceae' but are phylogenetically distant (<88% sequence similarity) 
from the known genera belonging to this family, including Prevotella, Hallela 
and Xylanibacter. On the basis of the phylogenetic analysis and physiological 
tests, strains YIT 11840T and YIT 11841T represent two novel species of a new 
genus, for which the names Paraprevotella clara gen. nov., sp. nov. (type strain 
YIT 11840T=JCM 14859T=DSM 19731T), the type species, and Paraprevotella 
xylaniphila sp. nov. (type strain YIT 11841T=JCM 14860T=DSM 19681T) are 
proposed.