Study On Taxonomy And Systematics Of The Lichen Genus Lecidella And Its Allies From China

The lichen genus Lecidella and its allies in China were studied. This lichen group includes the genera Lecidella, Carbonea, Clauzadeana, Miriquidica and Calvitimela and is characterized by the crustose thallus, lecideine apothecia, Lecanora-type and 8-spored asci, and the hyaline and simple spores. Lecidella was selected as the main group in this study because of its largest species diversity and widest distribution of the five genera. The materials for this study are about 1500 lichen specimens which were collected from 22 provinces of China and deposited in the herbaria HMAS?L, KUN, F and SDNU, respectively. The specimens were examined and identified by combining the morphological, chemical and ecological features. Specimens representing the range of morphological and chemical variation were selected for the multi-locus molecular phylogenetic investigations. The results were as follows:1. The species diversity and distribution of lichen genus Lecidella and its allies from China were studied systematically. 25 taxa belonging to 5 genera were included in this study with detailed descriptions in morphology, anatomy, chemistry and geographical distribution. Each species was discussed with its similar taxa. The key to the 5 genera and the keys for the species of genera Lecidella, Miriquidica and Calvitimela were provided. The photographs of morphology and anatomy for each species were also attached. One new species to science― Miriquidica yunnanensis Lu L. Zhang & X. Zhao, one new genus to China―Clauzadeana Cl. Roux and four new species to China―Lecidella oceanica Lu L. Zhang & Xin Y. Wang, Lecidella tumidula(A. Massal.) Knoph & Leuckert, Clauzadeana macula(Taylor) Coppins & Rambold and Miriquidica obnubila(Th. Fr. & Hellb.) Hertel & Rambold were reported in this study.2. The molecular phylogenies of Lecidella and its relatives and the species of Lecidella in China were studied based on multi-locus data using ML and Bayesian analyses for the first time. The topologies of the two analyses were almost coincident. The genus Lecidella as currently circumscribed was recovered as a high supported monophyletic clade and formed a sister-group relationship with Lecanora sensu stricto. The Lecidella species fell into three major clades, which were proposed here as three informal groups―Lecidella stigmatea group, L. elaeochroma group and L. enteroleucella group, each of them was strongly supported. The phylogenetic analysis supported traditional species delimitation based on morphological and chemical traits in most but not all cases. Individuals considered as belonging to the same species based on phenotypic characters were found to be paraphyletic, indicating that cryptic species might be hidden under these names(e. g. L. carpathica and L. effugiens). Potentially undescribed species were found within the phenotypically circumscribed species L. elaeochroma and L. stigmatea.