Two epiphyllous liverworts, Cololejeunea dozyana (Sande Lac.) Schiffn. and Cololejeunea sigmoidea Jovet-Ast and Tixier (Hepaticae, Lejeuneaceae), new to Taiwan

Two epiphyllous species of the genus Cololejeunea (Hepaticae, Lejeuneaceae), C. dozyana (Sande Lac.) Schiffn. and C. sigmoidea Jovet-Ast and Tixier, are reported for the first time from Taiwan. Cololejeunea dozyana is related to C. macounii (Spruce ex Underw.) A. Evans, whereas C. sigmoidea is similar to C. formosana Mizut. and C. rotundilobula (Wu and Lin) Piippo. A distribution map of C. dozyana and C. sigmoidea and distinctions from related species are provided. Descriptions and illustrations of the two species based on local specimens are also presented.