Siphocranion

Abstract: Phylogenetic analyses of Isodon and related genera using the nuclear ribosomal internal transcribed spacer (nrITS), cpDNA regions (trnL-trnF region and rps16 intron), and morphological data are presented. The results clarify the relationships among Isodon and its putative related genera and the question of the monophyly of Isodon and its relationship with Siphocranion. Siphommion is a nionophyletic genus and the sister clade to the remaining species; the ne N, subtribe Siphocranioninae of tribe Ocirucae is described to accommodate it. lsodon, as currently circumscribed, is onI, monophyletic if Skalwithus oreophiffiS is included in it. lsodoii forms a distinct SUbtribe lsodoninae within tribe Ocitneae and three strongly supported subclades are identified within the genus. In addition, a close relationship between Hanccohl and Hyptis is indicated in the combined nrlTS + cpDNA data set with Bayesian inference and this is also supported in morphological analysis, but more Studies are needed to confirm this relationship. It is evident that SUbtribe Hanceolinae is polyphyletic as currently defined, so subtribe Hanceolinae is restricted to accommodate Hanceola alone. The relationships between Isodon and other genera within tribe Ocimeac are still unresolved: the newly erected SUbtribe lsodoninae is a monophyletic group representing a distinct lineage in subtribe Ociminae. The relationships among the species of the largest subclade C of Isodon are still poorly known. Additional Studies Of this group with additional data and more intensive taxon sampling might help to resolve these issues.

Abstract: Siphocranion is an oligotypic genus of Lamiaceae, with two species mainly distributed in subtropical China and one of them found also in northeastern India, Myanmar, and Vietnam. Based on field investigation, morphological comparison, and molecular phylogenetic analyses, a new species of Siphocranion from the Sino-Vietnamese border is described as S. flavidum. Bayesian and maximum likelihood analyses on two nuclear ribosomal DNA regions and six plastid DNA regions reveal that S. flavidum is a distinct species in the genus and may be sister to the clade formed by the remaining two species of Siphocranion. Morphologically, the new species differs from S. macranthum and S. nudipes in its strigose stem with dark purple spots, thick papery lamina, significantly larger calyx, pale yellow corolla with tube slightly saccate at anterior side of base.