A Morphological Cladistic Analysis of Gentianaceae-Canscorinae and the Evolution of Anisomorphic Androecia in the Subtribe

Abstract We investigated cladistic relationships among the genera and species of paleotropical Gentianaceae-Canscorinae using morphological characters. Twenty-five characters were scored across all 23 species of the subtribe plus four outgroup species representing the closely related Coutoubeinae and Chironiinae. The maximum parsimony analysis resulted in one most parsimonious tree of 91 steps. The seven genera of Canscorinae fall into two major clades. These comprise Cracosna, Hoppea, Schinziella, and Canscora (clade I), and Microrphium, Phyllocyclus, and Duplipetala ined. (clade II). Intergeneric relationships were highly congruent with earlier molecular analyses in which, however, not all genera were included. Phylogenetic relationships among genera imply that the two different types of anisomorphic androecia found in Canscorinae evolved independently. An ancestral area analysis showed that Canscorinae are likely to have originated in SE Asia. From there India was colonized by the Canscora, Hoppea, Sch...