Osteological variation of the olive barb Puntius sarana (Cyprinidae) in Sri Lanka

Abstract

Osteological intra-specific variation was studied in olive barb Puntius sarana Hamilton 1822, from six water bodies in Sri Lanka. Discernible variation was reported in the elements of the cranium, pharyngeal bones and caudal skeleton of the fish. The curvature of the median suture between frontals of the skull roof in fish from the rivers Walawe, Nilwala and the Kirindi Oya was directed opposite to that in fish from the rivers Menik, Gin and Kalu. Shape of the tip of dorsal limb of the pharyngeal bones was either most commonly pointed or truncated. Consistent distinctiveness in the rudimentary neural arch of the compound centrum was observed in the Walawe River population, while double neural spines were present on preural centra (PU2 or PU3) of the caudal skeleton in some populations. The size of the parhypural foramen and epural distance in the caudal skeleton, and the total number of vertebrae of the axial skeleton also showed variation. The results are the first information on osteological variation of P. sarana in Sri Lanka.