Phylogeny of the Madagascan endemic family Didiereaceae

A molecular phylogeny of the Didiereaceae was produced through parsimony an alysis of chloroplast rpl16 intron and trnL-trnF and trnT-trnL intergenic s pacer sequences of all eleven species of the Didiereaceae and several outgr oup taxa from the Portulacaceae. Results indicated that: 1) the Didiereacea e were embedded within the Portulacaceae. with Calyptrotheca as the sister group of the family; 2) present generic limits were supported, 3) Alluadiop sis was the most basal lineage: 4) at least two separate episodes of polypl oidization within the genus Alluaudia had occurred, and 5) unusually low am ounts of variation were present in rapidly evolving noncoding plastid seque nces.