The genus Echinopsis comprises a polyphyletic group of columnar cacti with hermaphrodite, actinomorphic flowers, displaying diverse floral phenotypes and attracting a varied flower visitors. In Chile, the genus includes seven taxa, notably the Echinopsis chiloensis complex with three sub-species: E. c. chiloensis, E. c. litoralis, and E.c. skottsbergii. In this work, evaluated different reproductive traits that could be accounting for restrictions in gene flow between the different subspecies of the complex, as reproductive biology, floral visitors, floral morphology, nectar production and pollen limitation, including the specie E. bolligeriana, previously part of the complex. Results indicate all species are self-incompatible with diurnal anthesis, except for southern E.c. chiloensis populations (here E.c. australis). Only, detected small morphological differences distinguish between E. c. litoralis and E. bolligeriana, despite which, the pollinator assemblages presented diferences on the identity of pollinators and visit frequencies , displaying highs modularity between subspecies. Nectar sugar production and concentration remain constant throughout flower opening, except for E. c. litoralis, which produces nectar only in the morning, despite hosting a diverse pollinator assemblage with significant dipteran presence. Distinctions in morphological characters, nectar production, and pollinator assemblages account part for the persistence of subspecies differences, and potentially play a vital role in subspecies genetic isolation