Siphonolejeunea elegantissima

White- to yellow-green patches, closely appressed to fern fronds, autoicous. Specialised asexual propagules absent. Leaves oblong, 400–800 μm long, 200–425 μm wide, rounded at apex, spreading patently, remote or imbricate, overlapping stem dorsally and extending beyond other side of stem, usually obscuring the stem from above, attached to stem by three cells; lobe margins crenulate by protruding papillae, otherwise entire, attached to lobule by straight or slightly bulging keel that seamlessly continues line of lobe margin; lobule rectangular-cylindric, 160–380 μm long, 50–110 μm wide, with the free edge opposite keel revolute, without obvious teeth, with hyaline papilla inserted half way along edge opposite from stem and about 2 cells from corner of lobule; cells circular, rounded-quadrate, rounded-polygonal or elliptic, 12–30 μm long, 11–23 μm wide, smallest toward margin, thin-walled, with prominent triangular trigones in the lobe, without trigones in the lobule, with a large prominent central papilla on adaxial surface of lobe, smooth abaxially and on lobule cells. Underleaves divided 4/7–2/3 into two lobes, 100–250 μm long, 75–220 μm wide; lobes narrowly lanceolate, not divergent, separated by a rounded sinus, 2–4 cells wide at base, terminating in a single row of 2–4 cells. Perianth pyriform, 5-keeled, 500–650 μm long, 375–450 μm wide, cells papillose like adaxial leaf surface, apex depressed and without a beak.