Pollen morphology of Tetraglochin (Sanguisorbeae): A contribution to the understanding of the fossil record of Rosaceae

Abstract

The present study describes and illustrates for the first time the pollen morphology of the six species of genus Tetraglochin (Rosaceae, Sanguisorbeae) using light microscopy (LM). T. acanthocarpa, T. alata, T. andina, T. caespitosa, T. cristata and T. inermis were compared with the pollen fossil record with rosaceous affinity. The fossil form that presents a greater similarity with the species studied is Psilatricolporites quenua (Río Leona Formation, Late Oligocene, Santa Cruz, Argentina). P. quenua presents a marked similarity with Tetraglochin in all measured characters and in its ornamentation. Previous paleobiogeographic interpretations were evaluated considering the new data provided in this contribution.