Taxon cycles in Lungfish (Sarcopterygii: Dipnoi)

Since their origin 300 MYBP, lungfish underwent an initial period of rapid morphological innovation through the Paleozoic (rapid origination and extinction of short-lived genera, as indicated by solid bars), and have since developed relatively few new characteristics (persistence of a few long-lived genera afterwards). There are currently three monotypic genera, one each in Africa, Australia, and South America. (from Stanley 1978, after Westoff 1949).