*Valentí Rull, Palynology and Paleoecology Group, CSIC–Botanic Institute of Barcelona, Passeig del Migdia s/n, 08038 Barcelona, Spain.
E-mail: vrull@ibb.csic.es


The concept of microrefugia is widely accepted to explain the post-glacial colonization of continents, which led to the present-day biotic configuration of the Earth. However, so far, microrefugia are no more than a ‘theoretical necessity’ without an appropriate biogeographical and ecological characterization. Here, a tentative definition and a classification of microrefugia, based on the existing literature, are proposed for discussion. A deeper biogeographical analysis of the concept is suggested using novel ecological models and methods, in order to develop new hypotheses to be tested with palaeoecological and molecular phylogenetic tools.