Lejeunea (sect. Papillolejeunea) Gradst. & G. E. Lee, stat. nov.

[Clade XIII]Lejeunea sect. PapillolejeuneaGradst. & G. E. Lee stat. nov. Papillolejeunea Pócs (Pócs 1997: 2) Type species Papillolejeunea balazsii Pócs (= L. balazsii (Pócs) R. M. Schust.). Description Plants dioicous or paroicous, greatly varying in size, stems with few to many medullary cell rows (3–35). Leaf surface smooth or with slime papillae. Lobules frequently large, to 1 / 2 × leaf length, and with two teeth, first tooth sometimes stylus-like prolonged, to three cells long, hyaline papilla entally displaced. Cuticle smooth or punctate-papillose. Oil bodies finely granular (L. colensoana, L. tumida). Male bracteoles restricted to the base of the male spike. Gynoecia: innovations usually repeatedly fertile. Perianths eplicate or 5 - keeled, keel smooth or crenate. Asexual reproduction by specialized devices absent. Distribution Southeast Asia-Australasia; centre of species diversity in the mountains of New Guinea. Species Lejeunea balazsii, L. candida Pócs, L. colensoana (Steph.) M. A. M. Renner, L. gradsteinii G. E. Lee, Damanhuri & Latiff, L. stephaniana Mizut., L. tumida Mitt. Further species (not sequenced) Lejeunea falcata (Pócs & J. Eggers) Pócs, L. koponenii (Pócs & J. Eggers) Pócs, L. touwii (Pócs) R. M. Schust. Notes The distinctive characters of sect. Papillolejeunea are the strongly inflated and often large lobules (to half the lobe length) with a stout, to 3 cells long tooth and an entally displaced hyaline papilla. In other sections of Lejeunea, the hyaline papilla is positioned on the leaf margin or, occasionally, at the tip of the tooth in species with a prolonged, stylus-like tooth (sect. Heterolejeunea: L. setacea, L. trinitensis). The usually repeatedly fertile innovations, with rows of up to four gynoecia, and the absence of asexual reproduction are further characteristics of this section. The occurrence of slime papillae on the dorsal leaf surface, seen in L. balazsii and L. koponenii, is an autapomorphy of the section. The centre of diversity of sect. Papillolejeunea are the mountains of New Guinea, where five species occur. Three of them (L. falcata, L. koponenii, L. touwii) have not been sequenced and are included in the section on morphological grounds because of their morphological similarity to the type species. References Pócs (1997), Schuster (1998), Pócs and Eggers (1999), Renner et al. (2010, 2021), Lee (2013).