It is practically difficult to differentiate
from Red River drainage of China. Without stated reasons, P. robustus
has been assumed as the synonyms of P. caudofasciatus
. The present study aims to decipher the morphological differences between two species so as to provide reliable clues for their classification by multivariate morphometry. A total of 72 specimens of two species in genus Placocheilus
were examined. Besides morphological character comparisons, 10 anatomic landmarks were utilized and 23 frame structures and 15 general characters measured. The scatter plot results of principal component analysis showed that all specimens were clustered together and could not be defined as two distinct species. No significant morphological differences existed in four diagnostic characters between P. robustus
and P. caudofasciatus
. Thus the results of the present study fail to support P. robustus
as a valid and independent species.