We discuss the phylogeny of the predominantly Neotropical subtribe Spiranthinae, and more broadly of tribe Cranichideae, on the basis of cladistic analysis of 90 sequences each of two protein-coding plastid genes (rbcL and matK), two non-coding plastid regions (trnL intron and trnL-F intergenic spacer), and the nuclear ribosomal ITS region. These include representatives of all the subtribes currently recognized as belonging in Cranichideae (except the monotypic Manniellinae) and representatives of tribes Diurideae (identified by independent works as sister to Cranichideae), Orchideae (including Diseae), and Codonorchideae (outgroups). The five datasets produced highly congruent patterns of relationship and were thus analyzed in combination. This analysis confirms the close relation of both Chloraeinae and Pterostylidinae to the "core" Cranichideae indicated by previous studies of rbcL (Cameron et al., 1999; Kores et al., 1997) and matK sequences (Kores et al., 2000), with Chloraeinae sister to a clade including Pterostylidinae plus Megastylis and the core Cranichideae. Within the latter, Pachyplectroninae are strongly supported as sister to a monophyletic Goodyerinae, and this clade is sister to the rest of Cranichideae. Spiranthinae as delimited by Dressler (1993) are not monophyletic unless Galeottiella is excluded, and Prescottiinae are a paraphyletic grade with Cranichidinae embedded in them.

Key words: coding and non-coding plastid sequences, ITS, Orchidaceae, Phylogeny, Spiranthinae