Combined genotypic–phenotypic phylogeny of the tribe Spathicarpeae (Araceae) with reference to independent events of invasion to Andean regions

摘要

The Neotropical tribe Spathicarpeae is noteworthy within the family Araceae for having members occurring in very dry and/or very high (above 3000 m) areas in South America. Considering the small size of previously included genera in the tribe (10 geophytic genera, none with more than 15 described species), generic circumscription has been considered troublesome. To address these issues, we sequenced two cpDNA markers (matK and trnL-F) and reconstructed the phylogeny of the tribe using two approaches: Maximum parsimony and Bayesian Inference. We also evaluated the effect of adding phenotypic characters in a “total evidence” analysis. Our results confirm the previous suggestion that the two non-geophytic genera Dieffenbachia and Bognera should be included in Spathicarpeae, but the precise placement of Bognera within the tribe is still unresolved. Our results also support the segregation of Asterostigma pavonii and Asterostigma integrifolium, recently described as new monospecific genera (Incarum and Croatiella, respectively). The reconstructed phylogenies suggest that the invasion of the Andean range by the Spathicarpeae occurred in at least two independent events. The inclusion of phenotypic characters in a combined analysis has improved both internal resolution and the number of strongly supported clades.