Lycopodiaceae are one of the oldest lineages of any living vascular plants and contain about 400 species distributed on all continents except Antarctica, with its highest diversity in tropical regions. Previous studies on the morphology, anatomy, and molecular systematics of Lycopodiaceae have made substantial progress in understanding the diversity and evolution of the family, but major issues remain. In particular, earlier studies had relatively sparse taxon sampling, some critical relationships among the genera have not been well resolved, and the monophyly of some genera (e.g., Huperzia, Lycopodiella, Pseudolycopodiella, Spinulum) has not been robustly tested with large sampling. In this study, we apply a dataset of 1150 DNA sequences of seven plastid markers (atpA, psbA-trnH, rbcL, rps4, rps4-trnS, trnL, trnL-F) of 334 accessions representing ca. 155 (ca. 39% of all) species in the family to infer a global phylogeny. Our major results include: (1) the tree is resolved into three primary clades corresponding to the three subfamilies, Huperzioideae, Lycopodioideae, and Lycopodielloideae; (2) these three primary clades are resolved into 17 major clades, of which 16 represent genera recognized in the PPG I classification, while Lycopodiella serpentina is resolved as sister to Palhinhaea, and thus a new genus, Brownseya is given.
NEW GENUS:
Brownseya Li Bing Zhang, L.D.Sheph., D.K.Chen, X.M. Zhou & H.He, gen. nov. – Type: Brownseya serpentina (Kunze) Li Bing Zhang, L.D.Sheph., D.K.Chen, X.M. Zhou & H.He (≡ Lycopodium serpentinum Kunze)
Diagnosis. Brownseya is similar to Lycopodiella in having strobili terminal and solitary on erect stems and growing in wetlands, but the former has strongly dimorphic leaves with sterile leaves (tropophylls) clearly longer than fertile leaves
(sporophylls), whereas the latter has nearly monomorphic leaves. Brownseya is also similar to Lateristachys (lateralis) in having slender plants and growing in wetlands, but the former has long-stalked, solitary, and terminal strobili, whereas the latter has non-stalked (or shortly so) multiple strobili borne on sides of the erect stems.
Description.–Horizontal stems dichotomously branching, prostrate; leaves imbricate, ascending, linear to narrowly triangular. Aerial stems erect, unbranched. Leaves strongly dimorphic with sterile leaves (tropophylls) clearly longer than fertile leaves (sporophylls). Sterile leaves monomorphic, spirally arranged, appressed or spreading, linear to narrowly triangular, apices acuminate. Strobili solitary, terminal on branches, erect, long-stalked. Sporophylls arranged in alternating whorls of 5 or more, forming 10 or more longitudinal ranks.
This genus may contain 2–4 species.
Some photos of Brownseya serpentina. A, Habitat; B & C, Habit; D, Strobili; E, Creeping stems.
Source: De-Kui Chen,Xin-Mao Zhou,Carl J. Rothfels,Lara D. Shepherd,Ralf Knapp,Liang Zhang,Lữ Thị Ngân,Xue-Ping Fan,Xia Wan,Xin-Fen Gao,Hai He,Li-Bing Zhang. A global phylogeny of Lycopodiaceae (Lycopodiales; lycophytes) with the description of a new genus, Brownseya, from Oceania. TAXON, 6(71), 1-27, 2021, ISSN: 400262.
News: Lu Thi Ngan, Vietnam National Museum of Nature, VAST