Sexual dimorphism is the variation in the morphology between individual’s sexes that belongs to the same species. Morphological variation in fishes can be attributed to sexual dimorphism. Fish species are known for their large phenotypic plasticity in life-history traits in relation to environmental characteristics. Plasticity allows species to increase their fitness in a given environment. Mesoprites cancellatus is an exceptional species found in Tagoloan River, Misamis Oriental. The primary objective of this study is to describe the variations in the morphology of M. cancellatus so as to determine if sexual dimorphism exists within the species, using relative warp analysis. A total of 3 specimens were sampled, 15 males and 15 females, 130 closely connected points were made on the outline of the body and 50 connected points were made on the caudal fin and were digitized using tpsDig program version 2.12 [5] and subjected into relative warp analysis from where relative warp scores were derived. Thin-plate spline plot, Discriminant Function Analysis and MANOVA showed significant variation in the body shape and caudal fin shape between sexes. However, it is in the body shape that exhibits greater morphological variation compared to the caudal fin shape.
