Phylogenetic insights into Remototrachyna (Parmeliaceae) and their Trebouxia symbionts found in the Western Ghats, India

This study investigates the phylogeny and symbiotic relationships of the foliose lichen genus Remototrachyna, R. crenata and R. rhabdiformis from the Western Ghats through morphological, chemical and molecular phylogenetic tools using concatenated ITS and LSU data analyses. The study further identified the photobiont Trebouxia species in R. crenata and R. rhabdiformis based on ITS sequence data and phylogeny. The Trebouxia species of R. crenata and R. rhabdiformis were delineated as a major clade closely related to Trebouxia sp. voucher SF31 sequenced from Usnea ghattensis belonging to Trebouxia Clade I. This study represents a pioneering effort to unravel the enigmatic lichen symbiosis that exists in the genus Remototrachyna from the Western Ghats of India.