The pollen of Cliococca selaginoides (Lam.) C. M. Rogers & Mildner and eight Linum L. species from Argentina were examined using light and scanning electron microscopy. Both genera share pollen grains which are 3-zonocolpate, isopolar, radiosymmetric, spheroidal and medium to large in size. The sculptural elements of the exine are gemmae or clavae, which allow the genera to be distinguished and the species to be characterised. In Cliococca Bad., the pollen is exclusively gemmate whereas in Linum the pollen is gemmate and clavate (except in L. catharticum L. whose pollen has only gemmae which are apically microechinate). The statistical analyses of quantitative and qualitative morphological characteristics were performed. A key to identify and distinguish the pollen types and subtypes is also provided. A generalized procrustes analysis (GPA) of joint characterisation based on both qualitative and quantitative characters identified four distinct groups.