Systematic Botany (2018), 43(3): pp. 645–655 © Copyright 2018 by the American Society of Plant Taxonomists DOI 10.1600/036364418X697364 Date of publication August 10, 2018 Infrageneric Revision of the Fern Genus Deparia (Athyriaceae, Aspleniineae, Polypodiales) Li-Yaung Kuo,1,7 Atsushi Ebihara,2 Tian-Chuan Hsu,3 Germinal Rouhan,4 Yao-Moan Huang,5 Chun-Neng Wang,1,6,8 Wen-Liang Chiou,3 and Masahiro Kato2 1Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei 10617, Taiwan 2Department of Botany, National Museum of Nature and Science, Amakubo 4-1-1, Tsukuba, Ibaraki 305-0005, Japan 3Botanical Garden Division, Taiwan Forestry Research Institute, Taipei 10066, Taiwan 4Mus´eum national d’Histoire naturelle, Institut de Syst´ematique, Evolution, Biodiversit´e ((ISYEB) CNRS, Sorbonne Universit´e EPHE), Herbier national, 16 rue Buffon CP39, F-75005 Paris, France 5Silviculture Division, Taiwan Forestry Research Institute, Taipei 10066, Taiwan 6Department of Life Science, National Taiwan University, Taipei 10617, Taiwan 7Current address: Boyce Thompson Institute, Ithaca, New York 14853, USA ([email protected]) 8Author for correspondence ([email protected]) Communicating Editor: Sven Buerki Abstract—Current molecular phylogenetic analyses support the monophyly and circumscription of the athyrioid fern genus Deparia (Athyr- iaceae), which includes previously recognized genera including Athyriopsis, 3Depazium, Dictyodroma, Dryoathyrium (5 Parathyrium), Lunathyrium, and Neotriblemma (5 Triblemma Ching), and 3Neotribleparia. This broad generic concept has been adopted in several recent taxonomic treatments, including the Pteridophyte Phylogeny Group I. However, the infrageneric taxonomy of Deparia still needs further revision. In this study, we provide a new infrageneric classification with five sections and three subsections based on the phylogenetic evidence. We recognize two new sections, sect. Dictyodroma and sect. Erectus, and two new subsections, sect. Deparia subsect. Caespites and subsect. Athyriopsis. In addition, we provide a key to the sections and subsections, a table of diagnostic characters, new combinations for three Deparia and one Diplazium species, and a list of species assigned to the sections/subsections. Hybrids derived from crosses between the sections and subsections are also noted. Keywords—Athyrioids, Dictyodroma, sect. Erectus, taxonomy. The fern genus Deparia Hook. & Grev. was established in published a replacing genus name, Neotriblemma. Ching (1964) 1829 and based on Deparia macraei Hook. & Grev. [5 Deparia indicated that Athyriopsis is similar to Lunathyrium but dif- prolifera (Kaulf.) Hook. & Grev.; Fig. 1A]. In recent fern clas- ferent in its slender and non-winged stipe bases, absence of sifications and floristic treatments (e.g. Christenhusz et al. pneumatophores, and long-creeping rhizomes (Fig. 2). Dic- 2011; Rothfels et al. 2012b; He et al. 2013; PPG I 2016), Deparia tyodroma was recognized by a unique combination of anas- belongs to Athyriaceae, and encompasses several genera that tomosing venation, winged distal pinnae and entire proximal had long been kept separate: Lunathyrium Koidz., Dry- pinnae, hairlike scales (a kind of indument morphologically oathyrium Ching (5 Parathyrium Holttum), Athyriopsis Ching, transient from multicellular hairs to scales), and discontinuous Dictyodroma Ching, Neotriblemma Nakaike (5 Triblemma grooves between rachises and costae (Fig. 2). Neotriblemma was Ching), 3Depazium Nakaike, and 3Neotribleparia Nakaike. characterized by having diplazioid sori (i.e. paired but non- Lunathyrium was established by Koidzumi (1932) and based on connected sori on both sides of veinlets), long-creeping rhi- Lunathyrium pycnosorum (Christ) Koidz. [[ Athyrium pycno- zomes, and tuberculate perine (Ching 1978). In addition, Wang sorum Christ [ Deparia pycnosora (Christ) M. Kato; Fig. 1C]; it is (1982) established a new section under Athyriopsis, sect. characterized by its pneumatophores and almost asplenioid Caespites, based on Athyriopsis omeiensis Z. R. Wang [[ Deparia sori (i.e. linear and restricted to the acroscopic sides of veinlets; omeiensis (Z. R. Wang) M. Kato], characterized by its erect Fig. 2). Ching (1941) described Dryoathyrium based on Dry- rhizomes. 3Depazium, originally described as a nothogenus oathyrium boryanum (Willd.) Ching [[ Aspidium boryanum resulting from a cross between Deparia and Diplazium Sw., was Willd. [ Deparia boryana (Willd.) M. Kato], which is charac- based on 3Depazium tomitaroanum (Masam.) Nakaike [[ terized by the non-scaly stipe bases, creeping rhizomes, and Deparia 3tomitaroana (Masam.) R. Sano] (Nakaike 1992). One round-reniform (Fig. 2J) to U- and J-shaped sori. Holttum of the parent species of this hybrid is Diplazium subsinuatum, (1958) described the genus Parathyrium, also based on Deparia which is now, however, a synonym of Deparia lancea. Similarly, boryana, emphasizing its swollen stipe bases, presence of 3Neotribleparia was originally published for inter-generic hairlike scales, and discontinuous grooves between rachises hybrids between Neotriblemma and Deparia (Nakaike 2004) and costae (Fig. 2E and 2I). Ching (1964, 1978) recognized three but Neotriblemma is now included under the genus Deparia. additional new genera, Athyriopsis, Dictyodroma, and Tri- Affinities of species treated under the genera Athyriopsis, blemma, based on Athyriopsis japonica (Thunb.) Ching [[ Dryoathyrium, and Lunathyrium were first indicated by Asplenium japonicum Thunb. [ Deparia japonica (Thunb.) M. Tagawa (1959), and they were transferred to Lunathyrium by Kato; Fig. 1D], Dictyodroma heterophlebia (Mett. ex Baker) Kurata (1961). Taking Kurata (1961) and Ching (1964) into Ching [[ Asplenium heterophlebium Mett. ex Baker [ Deparia account, Ohba (1965) further established three sections within heterophlebia (Mett. ex Baker) R. Sano; Fig. 1G], and Triblemma Lunathyrium s. l.: sect. Lunathyrium, sect. Dryoathyrium, and lancea (Thunb.) Ching [[ Asplenium lanceum Thunb. [ Deparia sect. Athyriopsis. The morphological similarity between lancea (Thunb.) Fraser-Jenk. [ Neotriblemma lancea (Thunb.) Deparia prolifera and Lunathyrium s. l. was first noted by Kato Nakaike 5 Diplazium subsinuatum (Hook. & Grev.) Tagawa; (1977), who proposed four sections under Deparia, three of Fig. 1H], respectively. Because the genus Triblemma by Ching which were transferred from Lunathyrium s. l. This four-section (1978) is illegitimate due to the earlier name of Triblemma classification was detailed in the monographic work by Kato R. Br. ex C. Sprengel in Melastomataceae, Nakaike (2004) (1984); two subsections under sect. Athyriopsis were also 645 646 SYSTEMATIC BOTANY [Volume 43 Fig. 1. The diversity of Deparia (Athyriaceae). A. Deparia prolifera (Kaulf.) Hook. & Grev. B. Deparia dickasonii M. Kato. C. Deparia pycnosora (Christ) M. Kato. D. Deparia japonica (Thunb.) M. Kato. E. Deparia erecta (Z. R. Wang) M. Kato. F. Deparia parvisora (C. Chr.) M. Kato. G. Deparia heterophlebia (Mett. ex Baker) R. Sano. H. Deparia lancea (Thunb.) Fraser-Jenk. Photos: A by John Game; B, D, E, G by Li-Yaung Kuo; C, H by Pi-Fong Lu; and F by Germinal Rouhan. recognized by Wang (1982). The inclusion of Neotriblemma in deparioid genera as distinct: Athyriopsis, Dictyodroma, Dry- Deparia was first implied by Matsumoto and Nakaike (1990), oathyrium, Lunathyrium, and Neotriblemma (i.e. Triblemma). and Fraser-Jenkins (1997) pointed out the similarity in indu- The currently defined Deparia s. l. comprises 60–90 species, ment between Deparia lancea and Deparia sensu Kato (1984); with highest diversity in Asia but also distributed in Africa and this generic treatment was also supported by evidence from islands of the western Indian Ocean, northeastern North the rachis-groove morphology, cytology, and molecular America, the Hawaiian Islands, Australia, New Zealand, and phylogenetic studies (Nakato and Mitui 1979; Matsumoto and South Pacific Islands (Kato 1984; Rothfels et al. 2012b; He et al. Nakaike 1990; Sano et al. 2000b). Sano et al. (2000c) transferred 2013; Kuo et al. 2016, 2018b; PPG I 2016; and this study). Dictyodroma to Deparia, based on their cytological and mo- Irrespective of the marked taxonomic changes, this genus can lecular phylogenetic data (Sano et al. 2000a). However, the be distinguished from other athyrioids by both morphological species that were moved from Neotriblemma and Dictyodroma and cytological features. The hairlike scales (Fig. 2D, E), and still have not been assigned to any section. While He et al. the discontinuous grooves between rachises and costae (2013) transferred most Chinese species to Deparia, some (Fig. 2E) are the diagnostic and synapomorphic characters taxonomists (e.g. Chu et al. 1999) still recognized many (Kato 1973, 1977, 1984; Rothfels et al. 2012b; Sundue and 2018] KUO ET AL.: DEPARIA INFRAGENERIC REVISION 647 Fig. 2. Diagnostic characters in Deparia and other athyrioids. A. Cross section of broadly U-shaped rachis groove of Diplazium chinense (Baker) C. Chr. B. Narrowly U-shaped rachis groove of Deparia formosana (Rosenst.) R. Sano. C. V-shaped rachis groove of Athyrium opacum (D. Don) Copel. D. Hairlike scale of Deparia formosana (Rosenst.) R. Sano (upper) and gland-tipped hair of Deparia concinna (Z. R. Wang) M. Kato (lower) (provided by Li-Yaung Kuo). E. Discontinuous groove between rachis and costa of Deparia jiulungensis (Ching) Z. R. Wang; rachis and costae are covered by hairlike scales. F. Continuous groove between rachis and