Abstract: Hemagglutination assay of the extract from the hepatopancreas of the freshwater crab Travancoriana charu, using diverse mammalian erythrocytes revealed the presence of an agglutinin with specific affinity for rat > mice erythrocytes. Hemagglutinability was dependent on divalent cations and highly sensitive to the changes in the pH and temperature of the medium. Maximum agglutination was observed at pH 9.5 and temperature of 30ºC with the inclusion of 1-5 mM calcium or 1-10 mM manganese. HAI assay indicated the unique specificity of the agglutinin from the hepatopancreas to lactoferrin, a single subunit N-glycoprotein with Gal(α1-3)Gal(β1-4)GlcNAc(αGal),GalNAc(β1-4)GlcNAc(LacdiNAc) epitopes and N-glycolyl neuraminic acid (Neu5Gc).