Phylogeny of 'Carpha' and related genera (Schoeneae, Cyperaceae) inferred from morphological and molecular data

The limits, definitions and relationships of 'Carpha' have been controversial and unclear. This study using cladistic analyses of morphological and combined morphological and molecular data indicates that: (1) 'Carpha sensu latu' is paraphyletic and its species form two clades, consistent with the definitions of 'Carpha sensu stricto' and 'Asterochaete' respectively (i.e. the data support the division of 'Carpha sensu latu' into two genera: 'Carpha sensu stricto' and 'Asterochaete'); (2) the morphological data show a high degree of homoplasy within 'Schoeneae'; (3) 'Schoeneae' is not a monophyletic tribe; (4) 'Schoenus' and 'Tricostularia' are polyphyletic; (5) it is better to place 'Schoenoides' back in 'Oreobolus'; (6) separation of 'Capeobolus brevicaulis' from 'Costularia' or 'Tetraria' is supported; and (7) both genera 'Costularia' and 'Tetraria' should be maintained. The study resolves some phylogenetic relationships between 'Carpha' and its relatives. Many aspects of these relationships are in agreement with previous studies, but some of these relationships have no support. The study also resolves the phylogenetic relationships of species of 'Carpha', although with lack of support for some clades, highlighting the need for other sources of data.