Numerical analyses in the classification of the Pleurothallidinae (Orchidaceae)*

Anatomical and floral data were collected from 202 species in 34 genera or species complexes of the Pleurothallidinae (Orchidaceae). A data matrix was compiled from scorings of 45 continuous or discrete variables, including 35 vegetative characters and 10 floral characters. Different cluster and factor analyses were performed with this data matrix in order to identify phenetically similar taxa and at the same time reveal differences in results owing to different statistical procedures. Regardless of the clustering method applied, several genera or complexes are measurably distinct from each other and all other Pleurothallidinae, notably Dracula, Dresslerella, and the Pleurothallis alexandrae and Pleurothallis peduncularis complexes. After further, confirmatory studies, it may become appropriate to erect new genera for the Pleurothallis alexandrae and Pleurothallis peduncularis complexes. Phenetic relationships identified suggest at least seven major phylogenetic lines in the subtribe, which represent adaptations to both the epiphytic regime and dipteran pollination.