MULTIGENE EVIDENCE REVEALS THE SYSTEMATIC POSITION OF PLEUROCLADOPSIS SIMULANS (C. MASSAL.) R. M. SCHUST. WITHIN SCHISTOCHILA DUMORT., SCHISTOCHILACEAE

摘要

The monotypic Pleurocladopsis, endemic to Chile, was established by Schuster in 1964 based on an earlier poorly known species Cephalozia (?) simulans C. Massal. The phylogenetic position of Pleurocladopsis simulans had been considered uncertain until it was placed in the family Schistochilaceae on account of the gynoecial and sporophytic characters. It has been assumed that Pleurocladopsis represents the starting point of evolution in Schistochilaceae. In the present study, the phylogenetic position and taxonomic status of Pleurocladopsis simulans are inferred from phylogenetic analysis of three chloroplast DNA sequence data. The result suggests that the genus was established solely based on the autapomorphic characters, thus obscuring its actual phylogenetic relationship with Schistochila and that these characters are later derived rather than ancestral. The result also confirms that the gynoecial and sporophytic characters are important in taxonomy, but they may be not sufficient at the infrafamilial level and at other lower taxonomic levels. In accordance with the results of the present study, Pleurocladopsis is synonymised with Schistochila, and the new combination Schistochila simulans (C. Massal.) Xiao L. He & Yu Sun is made.