RESUMO
Understanding how natural hybridization and polyploidizations originate in plants requires identifying potential diploid ancestors. However, cryptic plant species are widespread, particularly in Ceratopteris (Pteridaceae). Identifying Ceratopteris cryptic species with different polyploidy levels is a challenge because Ceratopteris spp. exhibit high degrees of phenotypic plasticity. Here, two new cryptic species of Ceratopteris, Ceratopteris chunii and Ceratopteris chingii, are described and illustrated. Phylogenetic analyses reveal that each of the new species form a well-supported clade. C. chunii and C. chingii are similar to Ceratopteris gaudichaudii var. vulgaris and C. pteridoides, respectively, but distinct from their relatives in the stipe, basal pinna of the sterile leaf or subelliptic shape of the fertile leaf, as well as the spore surface. In addition, chromosome studies indicate that C. chunii and C. chingii are both diploid. These findings will help us further understand the origin of Ceratopteris polyploids in Asia.
RESUMO
Paraphlomis is a genus of Lamiaceae with about 30 species distributed mainly in subtropical China. In this study, we carried out the first molecular phylogenetic analyses to elucidate the relationships within the genus based on two nuclear and four plastid DNA regions. Our results, which recovered a species of Matsumurella within Paraphlomis, indicate that the genus is not monophyletic. The two sections and most of the series previously described within the genus are also shown to be polyphyletic. Combining with morphological evidence, our study indicates that nutlet morphology rather than calyx morphology is of phylogenetic value for the infrageneric classification of Paraphlomis. Moreover, P. jiangyongensis, a new species from southern China, is here described, and P . coronata, formerly treated as a variety of P . javanica, is here resurrected as a distinct species within the genus.