An overview of the genus Schiffneriolejeunea (Marchantiophyta: Lejeuneaceae)
Gradstein, S. Robbert
Monographic studies on the liverwort genus Schiffneriolejeunea (Lejeuneaceae subfam. Ptychanthoideae) lead to the recognition of 14 species and 5 varieties. The genus is related to Caudalejeunea and Archilejeunea, and is recognized by glossy brown color, presence of Lejeunea-type and Frullania-type branches, rigid stems with enlarged dorsal epidermis cells, convolute leaves, elongate leaf cells, cordate trigones, segmented oil bodies, undivided underleaves, hypostatic male bracts, gynoecia without innovations, perianths with 2 ventral keels (or none) and an articulate seta. A synoptic treatment of the species and varieties of Schiffneriolejeunea is provided, with keys to fertile and sterile material, data on types and published illustations, and a brief discussion of differentiating characters, distribution and habitat. The genus is pantropical with nine species occurring in Africa, six in tropical Asia and two each in Australia and tropical America. The majority of the species are dioicous and have restricted distributional ranges; widespread species with intercontinental ranges are mostly heteroicous. The species grow on bark in moist tropical forest areas from sea level to 3100 m elevation. Most of the species are drought-tolerant heliophytes.