Ontogeny and phylogeny of Brownleea (Orchidoideae: Orchidaceae)

The phylogeny of the African orchidoid genus Brownleea was investigated, using morphological characters. It has been suggested that the genus may be of hybrid origin, a hypothesis supported by the presence of two very different types of stigma ontogenies. Morphological investigations of all the species revealed that two species have stigmas derived from all three carpel apices, the 'normal' situation in the Orchidaceae. The remaining five species have stigmas derived from only the median carpel, a very unusual situation found in the Coryciinae. A phylogenetic analysis of all available morphological data for all species supports the monophyly of the genus. based on several distinct synapomorphies. The variation in stigma ontogeny may be due either to parallelism, or to an earlier hybridization event. The analysis supported the recognition of several distinct groupings within Brownleea . Two of these groupings are supported irrespective of which putative parent is used as sister-group to the genus, while a third grouping is dependent on the use of the as sister-group.