Stamen and pollen heteromorphism linked to the division of labour in Melastomataceae species

•Stamen heteromorphism shows structural and functional roles in some melastomataceae species.•Pollinating anthers were larger and produced more numerous, and more viable, pollen grains than feeding anthers.•Stamen heteromorphism lead to subtle and specific differences in anthers and pollen morphology, which might contribute to their different functional role in Melastomataceae studied species.