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Recent molecular phylogenetic studies reported high diversity of Ruppia species in the Mediterranean. Multiple taxa, including apparent endemics, are known from that region, however, they have thus far not been exposed to phylogenetic analyses aimed at studying their relationships to taxa from other parts of the world. Here we present a comprehensive phylogenetic analyses of the R. maritima complex using data sets composed of DNA sequences of the plastid genome, the multi-copy nuclear ITS region, and the low-copy nuclear phyB gene with a primary focus on the Mediterranean representatives of the complex. As a result, a new lineage, 'Drepanensis', was identified as the seventh entity of the complex. This lineage is endemic to the Mediterranean. The accessions included in the former 'Tetraploid' entity were reclassified into two entities: an Asia-Australia-Europe disjunct 'Tetraploid_α' with a paternal 'Diploid' origin, and a European 'Tetraploid_γ' originating from a maternal 'Drepanensis' lineage. Another entity, 'Tetraploid_β', is likely to have been originated as a result of chloroplast capture through backcrossing hybridization between paternal 'Tetraploid_α' and maternal 'Tetraploid_γ'. Additional discovery of multiple tetraploidizations as well as hybridization and chloroplast capture at the tetraploid level indicated that hybridization has been a significant factor in the diversification of Ruppia. [ABSTRACT FROM AUTHOR]

Nothapodytes (Icacinaceae) is a genus of seven to eleven evergreen or deciduous tree species distributed in tropical Asia from India to Japan. Nothapodytes nimmoniana sensu lato is the most widespread species of the genus, being reported sporadically throughout South Asia, Southeast Asia, Taiwan, and Japan’s southwest islands. Nothapodytes amamianus was recently described from Amami-oshima, Japan, the northeastern edge of this widespread species’ range. However, the phylogenetic distinction between these two species has yet to be explored. Here we present an analysis of molecular species delimitation to test the morphology-based taxonomic hypothesis currently used to differentiate the two species. The results clearly show that N. nimmoniana sensu lato comprises two species, one in India and the other in Taiwan and Japan, including N. amamianus, requiring a reassessment of the morphological traits hitherto used to define the former and distinguish it from the latter in East Asia. Based on the taxonomic history of the taxa and rules of nomenclature, the name N. nimmoniana is retained for the former. We propose a new combination, N. insularis, for the latter. Longitudinal intraspecific geographic structure is highlighted as an apparent indicator of further hidden diversity in India’s Western Ghats. [ABSTRACT FROM AUTHOR]