Paraphyly and phylogenetic relationships in Lasianthus (Rubiaceae) inferred from chloroplast rps16 data

A phylogenetic analysis of Lasianthus and some representatives of tribes in subfamily Rubioideae based on the chloroplast rps16 data indicates that Lasianthus as currently circumscribed is paraphyletic, because Saprosma crassipes, representative of the species with two locules per ovary developing into two pyrenes per drupe with a thin wall, and Litosanthes biflora, the species in the monotypic genus Litosanthes, are nested within the highly supported Lasianthus clade. The present delimitation of the tribe Lasiantheae, which includes Saldinia and Trichostachys, is supported by our results. Finally, our results are inconclusive for evaluating the monophyly of the infrageneric classification of Lasianthus.