Revision and distribution of Liparis species (Orchidaceae) in Amur region (Russia)

Abstract

In July 2018, in the Khingan State Nature Reserve and Muravyevskiy Park of Sustainable Development, we conducted the study of Liparis populations and preliminary determining the orchid individuals collected. In the family Orchidaceae, Liparis is one of the most difficult genera in terms of systematics. Observations in nature, research of herbarium specimens and literature demonstrate the considerable intraspecies variability in morphological traits. Therefore, to assess the taxonomic position of orchids from natural populations, we collected parts of the plants for further molecular-phylogenetic research. In total, we included 110 samples in the analysis. As a molecular marker, we used the internal transcribed spacers (ITS1–5.8S–ITS2) of 18S–26S nuclear ribosomal DNA. At the obtained phylogenetic tree, samples from the studied populations formed separate and clearly supported clades, that confirms their naturalness. ITS sequences of the analysed plants of each clade have group-specific substitutions, which mark their position on the phylogenetic tree. Analysis of both morphological traits and molecular-phylogenetic data allowed conducting species determination of plants from the genus Liparis. According to botanical literature, in the Amur region, two species were known: Liparis japonica and L. makinoana. The investigation of Liparis populations found in the field together with analysis results of morphological and molecular-phylogenetic data demonstrated that in the study area, besides L. japonica and L. makinoana, there are L. kumokiri and one more taxon, which could be a new species needed to be described in future. We clarified the distribution of these Liparis species in the study area by finding their new locations. The status of each population for studied species was appropriate at most of the locations. We noted the appropriate fruiting and offspring presence. At the studied location, permanent study plots could be established for conducting of further population-based studies. The obtained data on the status of plant populations will be used in the work on new editions of Red Data Books. In the study area, the presence of Liparis makinoana have not been confirmed by data of molecular-phylogenetic analysis.

Keywords

• molecular-phylogenetic study
• morphological traits
• phylogeny
• population status
• protected area
• rare species
• red data book