Morphometry and Phylogeny of the Different Populations of Selaginella tamariscina (P. Beauv.) Spring and S. pulvinata (Hook. & Grev.) Maxim. in Northern Thailand

Abstract

"Dok Hin” is the Thai local name for Selaginella species that form rosettes. They commonly distributes in Siberia, Manchuria, southern China, Japan, the Philippines and Thailand. Morphology of Dok Hin is very resemble leading to misidentification. So, exactly number of species of Dok Hin in Thailand and their differences in morphological characteristics is not well understood. Thus, revision of morphological characters and phylogenetic confirmation of the taxonomic identification are needed. This study aims to examine morphological charateristics and phylogenetic patterns in eight populations of the Dok Hin in Northern Thailand. Morphology of Dok Hin from each populations was quantitatively examined using 15 vegetative and 6 reproductive characters meanwhile phylogenetic analyses was explored by DNA barcode ITS2. The results of the phylogenetic analysis revealed the existence of two species of Dok Hin, S. tamariscina and S. pulvinata. Selaginella tamariscina can be distinguished from S. pulvinata by its presence of a pseudotrunk above ground and ridges of dorsal leaves. On the other hand, the results of phylogenetic analysis indicated the differences among populations of S. pulvinata as well. Chiang Mai populations of S. pulvinata was characterized by peculiar set of characters long leaves and leaf apices look like caudate, while the rest of their populations have shorter leaves and leaf apices look like aristate. It indicates that S. pulvinata has genetic and phenotypic divergence among populations. However, additional studies of Dok Hin populations in other parts of Thailand and studies on different genetic markers are necessary to confirm the taxonomic status of S. pulvinata.