XVI International Botanical Congess
Four major austral distribution patterns are evident in pteridophytes. Some 25 species are completely circum-antarctic. Another c. 41 species are partially circum-antarctic, occurring in Australasia and Africa-Madagascar but not South America, while c. 31 are in Africa-Madagascar and South America but not Australasia, and c. 11 are in South America and Australasia but not Africa-Madagascar. The role of continental drift versus long-distance dispersal of these species will be discussed, together with aspects of their ecology that may predispose towards long-distance dispersal.