Morphological characteristics were compared between three recorded species of rounded caudal fin
Oreonectes and specimens collected from Guan'an of Guangxi. The results showed the
Oreonectes
sp. from Guan'an was distinguished from
O. anphthalmus. Although some morphologic differentiations existed among
Oreonectes sp.,
O. polystigmus, and
O. platycephalus, their differentiations were not enough to distinguish between them. Consequently, we used multivariate morphometrics to determine their morphologic differentiation. Twenty-six frame characteristics and 20 general characteristics of 63 specimens were measured. The results of the Principal Component Analysis showed that
Oreonectes sp. and
O. polystigmus,and
Oreonectes sp. and
O. platycephalus occupied obviously different areas in the scatter plot. It is suggested that the specimens collected from Guan'an may be a cryptic new species of
Oreonectes. However, its taxonomic status should be decided by evidence from anatomical and molecular biological studies.
