Research Article |
Corresponding author: Yi-Shan Chao ( pteridaceae@gmail.com ) Corresponding author: Ho-Yih Liu ( hoyih@mail.nsysu.edu.tw ) Academic editor: Thais Almeida
© 2019 Yi-Shan Chao, Yu-Fang Huang, Shi-Yong Dong, Yao-Moan Huang, Ho-Yih Liu.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Chao Y-S, Huang Y-F, Dong S-Y, Huang Y-M, Liu H-Y (2019) Bolbitis lianhuachihensis (Dryopteridaceae), a new species from Taiwan. PhytoKeys 131: 69-81. https://doi.org/10.3897/phytokeys.131.36548
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A new species of Bolbitis, B. lianhuachihensis sp. nov., was found in central Taiwan. It most resembles B. virens var. compacta and B. hainanensis. A phylogenetic tree of Taiwanese and other Asian species of Bolbitis species supports the recognition of the new species. Morphologically, the combination of anastomosing venation and fewer sterile pinnae are critical characters to discriminate B. lianhuachihensis from other Taiwanese Bolbitis species. Bolbitis lianhuachihensis can be further distinguished from B. virens var. compacta and B. hainanensis by having lanceolate sterile pinnae and absent or fewer free veinlets in small areoles of sterile pinnae. The morphological descriptions, illustration, ecology and distribution of the new species are presented. A key to all Taiwanese Bolbitis is also provided.
Ferns, Taiwan, taxonomy, venation
Bolbitis Schott is a pantropical genus that belongs to Dryopteridaceae and consists of about 80 species (
In Taiwan, ten taxa have been recorded; namely, B. angustipinna (Hayata) H.Ito, B. appendiculata (Willd.) K.Iwats., B. heteroclita (C.Presl) Ching, B. laxireticulata K.Iwats., B. × nanjenensis C.M.Kuo, B. rhizophylla (Kaulf.) Hennipman, B. scalpturata (Fée) Ching, B. subcordata (Copel.) Ching, B. virens var. compacta Hennipman and B. heteroclita × B. subcordata (
In Taiwan, a Bolbitis plant appeared unusual due to its few sterile pinnae (Figs
The undescribed Bolbitis was collected in central Taiwan and herbarium specimens at HAST and TAIF were also studied. The keys, descriptions and illustrations in Hennipman’s monograph (1977) were investigated to compare the morphological characteristics of our suspected new species with the known Bolbitis species. Furthermore, the type specimens of two similar species in nearby regions, B. hainanensis (Wallich 1033, K) and B. virens var. compacta (Tagawa et al. 6802, L) were analysed. As the type specimen of B. hainanensis lacks fertile fronds, we also consulted the protologue (
To clarify the phylogenetic position of the undescribed plant, six more Bolbitis species from Taiwan and B. virens from China were sampled and sequenced in this study. Additional sequences of 19 species were gathered from GenBank, including 17 Bolbitis species and two outgroup species. Elaphoglossum lepervanchii and Teratophyllum koordersii were used as outgroups, based on the phylogenetic trees of Bolbitis and related taxa (
Total genomic DNA was extracted from young fronds, following a modified cetyltrimethylammonium bromide (CTAB) method (
Phylogeny was inferred by Maximum Likelihood (ML) analyses with GARLI v.2.0.1019 (
Based on the morphological study of the undescribed plant and type specimens of Bolbitis hainanensis and B. virens var. compacta (Suppl. material
Morphological comparisons amongst Bolbitis lianhuachihensis, B. hainanensis and B. virens var. compacta.
Characters | B. lianhuachihensis | B. hainanensis | B. virens var. compacta |
---|---|---|---|
Texture of laminae | Chartaceous | Coriaceous | Chartaceous |
Size of fertile pinnae | 5–9 × 0.8–1.2 cm | 6–10 × 1–1.5 cm | 4–11.5 × 0.8–2 cm |
Number of lateral pinnae of sterile fronds | 1–5 pairs | 2–3 pairs | 2–7 pairs |
Sterile pinna shape | Lanceolate | Oblong-lanceolate | Lanceate |
Size of sterile pinnae | 14–24 × 3–4.5 cm | 17–22 × 5–6 cm | 8–23 × 3–4 cm |
Bases of sterile pinnae | Cuneate | Narrowly cuneate | Narrowly cuneate or obtuse |
Margins of sterile pinnae | Entire | Entire or toothed | Entire |
Veinlets with an angle to costae of sterile pinnae | ca. 65° | 75°–80° | 75°–80° |
Row number of areoles between the costae and margins in sterile fronds | 2–4 rows | 3–4 rows | 4–5 rows |
Free veinlets in areoles of sterile fronds | Absent or very few | Present | Present |
The venation in sterile fronds of the unknown plant, Bolbitis hainanensis, B. virens var. compacta and other Bolbitis species in Taiwan is illustrated in Fig.
Venation patterns of sterile pinnae from all species of Bolbitis in Taiwan A Bolbitis angustipinna (Y.-F. Huang 176, TAIF) B Bolbitis appendiculata (Y.-F. Huang 243, TAIF) C Bolbitis heteroclita (Y.-F. Huang 221, TAIF) D Bolbitis heteroclita × subcordata (Y.-F. Huang 366, TAIF) E Bolbitis laxireticulata (Y.-F. Huang 228, TAIF) F Bolbitis × nanjenensis (Y.-F. Huang 213, TAIF) G Bolbitis rhizophylla (Y.-F. Huang 124, TAIF) H Bolbitis scalpturata (Y.-F. Huang 164, TAIF) I Bolbitis subcordata (Y.-F. Huang 254, TAIF) J Bolbitis lianhuachihensis (holotype specimen, Y.-S. Chao 3006, TAIF) K Bolbitis hainanensis (holotype specimen, C. Wang 35870, PE) L Bolbitis virens var. compacta (type specimen, Tagawa et al. 6802, L). The angles of veinlets to costae are indicated in B. lianhuachihensis (J), B. hainanensis (K), and B. virens var. compacta (L). Scale bars: 5 mm.
We also find the angles of veinlets to costae to vary. Considering the three similar taxa, the unknown plant has smaller angles than B. hainanensis and B. virens var. compacta (65°< 75° or 80°; Fig.
Three presumed hybrid taxa present intermediate venation morphology between their putative parents. Bolbitis heteroclita × B. subcordata has more free veinlets included in areoles than B. heteroclita, but fewer free veinlets included in areoles than B. subcordata. Most pinnae of B. laxireticulata, like B. appendiculata, have free veins, but some pinnae have anastomosing veins, similar to those of B. subcordata. Some pinnae of Bolbitis × nanjenensis have free veins like B. appendiculata, but some have costal areoles like B. heteroclita.
The chloroplast DNA (cpDNA) alignment of rps4-trnS and trnL-F contained 549 bp and 428 bp, respectively, with 239 parsimony-informative sites in total. The log-likelihood score for the most likely ML tree was -4989.8277. Our four specimens of Lienhuachih Bolbitis shared the same genotype and occupied a unique place that was well-separated from all other samples species in the phylogenetic tree, different from other Taiwanese Bolbitis species and B. virens var. virens (Fig.
Bolbitis virens var. compacta auct. non Hennipman: Knapp, Ferns Fern Allies Taiwan: 440. 2011.
TAIWAN. Nantou County: Lienhuachih, 700 m a.s.l., 11 March 2018, Yi-Shan Chao 3006 (holotype TAIF!, isotype TAIF!).
Bolbitis lianhuachihensis morphologically resembles B. virens var. compacta and B. hainanensis, from which it is distinguished in having lanceolate sterile pinnae and no free veinlets in areoles of sterile fronds.
Terrestrial or lithophytic. Rhizome short-creeping, thick, densely scaly; scales concolorous, black, lanceolate, 3–5 mm long, 0.5 mm wide, margin entire. Fronds clustered, 40–80 cm long, dimorphic, pinnate. Sterile fronds with stipes 18–50 cm long, near base 2–4 mm diam., scaly, glabrous upwards; lamina broad-ovate, 21–34 × 21–35 cm, chartaceous, conform; lateral pinnae 1–5 pairs, alternate, lanceolate, 14–24 × 3–4.5 cm, bases cuneate, margins entire, undulate, apices caudate or acuminate, basal two pairs of pinnae with winged petiolules < 8 mm; terminal pinna larger or similar to lateral pinnae, sometimes with a bulbil near the apex; veins reticulate, 2–4 rows, no or very few areoles with free veinlets in the largest pinnae (wider than 3.5 cm). Fertile fronds longer than or as long as the sterile ones; stipes 35–50 cm long; lamina oblong-ovate, 7.5–14.5 × 12–18 cm; pinnae 3–4 pairs, alternate, lanceolate, 5–7.5 × 0.8–1.2 cm, base narrow-cuneate, apex acuminate, stalked. Sporangia acrostichoid.
TAIWAN. Chiayi County: Tsenwen Dam, 24 Jan. 1987, Bi-Jao Wang 10039, 11009 (HAST, TAIF). Nantou County: Lienhuachih, 700 m a.s.l., Yih-Han Chang 20070317-008 (TAIF), 29 Aug. 2009, Cheng-Wei Chen Wade 955 (TAIF), 22 Mar. 2015, Cheng-Wei Chen Wade 4181 (TAIF), 29 Jan. 2016, Yu-Fang Huang 115, 116, 117 (TAIF), 10 Oct. 2005, Ralf Knapp 697 (P), 22 Oct. 2011, Ralf
Evergreen, broad-leaf forests, often near streams, below 1000 m a.s.l.
The specific epithet ‘lianhuachihensis’ refers to the type locality.
Lian Hua Chih Shih Jyue (蓮華池實蕨; Chinese name).
To date, only three small populations of Bolbitis lianhuachihensis Y.S.Chao, Y.F.Huang, & H.Y.Liu have been recorded in Taiwan. However, the estimated number of individuals is smaller than 250. It meets the category Endangered (EN D1) based on the
Bolbitis lianhuachihensis can be delimited by the combination of anastomosing venation and fewer sterile pinnae than any other species of Bolbitis in Taiwan. It was thought to be related to two similar taxa with “thick laminae” in nearby regions, B. virens var. compacta and B. hainanensis (
In this study, we revealed the venation diversity in the Taiwanese Bolbitis species and related taxa. Based on the illustration of venation, it is found that every taxon possesses its own venation morphology, supporting the taxonomic value of venation (
1 | Veins free | 2 |
– | Veins anastomosing | 3 |
2 | Sterile pinnae unequal at base, auriculate; pinna margins with sharp teeth in sinuses | B. appendiculata |
– | Sterile pinnae equal at base; pinna margins without sharp teeth | B. rhizophylla |
3 | Sterile fronds with few areoles, sometimes only a single series of costal areoles | 4 |
– | Sterile fronds with many areoles, more than one row of areoles between the costae and margins | 5 |
4 | Sterile pinnae linear-lanceolate | B. laxireticulata |
– | Sterile pinnae falcate | B. × nanjenensis |
5 | Sterile pinnae linear-lanceolate | 6 |
– | Sterile pinnae lanceolate | 8 |
6 | Sterile lateral pinnae 15–24 pairs, < 2 cm wide | B. angustipinna |
– | Sterile lateral pinnae <10 pairs, > 2 cm wide | 7 |
7 | The space between two secondary veins in sterile pinnae more than 7 mm wide | B. subcordata |
– | The space between two secondary veins in sterile pinna 3–6 mm wide | B. heteroclita × B. subcordata |
8 | Sterile terminal pinnae having extremely elongated apex | B. heteroclita |
– | Sterile terminal pinnae similar to lateral pinnae | 9 |
9 | Sterile pinnae < 3 cm wide | B. scalpturata |
– | Sterile pinnae > 3 cm wide | B. lianhuachihensis |
The authors thank Dr. Sen-Sung Cheng for his assistance in collecting plant samples and Ms. Pi-Fong Lu for her photograph. The curators of herbaria B, HAST, L, PE and TAIF are gratefully acknowledged for their loan of specimens. This research is supported by Ministry of Science and Technology of Taiwan (MOST106-2311-B-037-005-MY3) for Y.S. Chao.
Voucher specimens and GenBank accession numbers for DNA sequences used in this study. Information is presented in the following order: species, voucher, locality, GenBank numbers for rps4 and trnL-F , herbarium. “*”Newly published sequences in this study; “–“ no data.
Bolbitis acrostichoides , Faden s.n., Uganda, GU376645, GU376501, US. B. aliena, Jimenez 2634, Bolivia, GU376646, GU376502, NY. B. angustipinna, Huang 170, Taiwan, MK639320*, MK978743*, TAIF. B. appendiculata, Huang 0112, Taiwan, MK639321*, MK978743*, TAIF. B. auriculata, Rouhan 183, Mauritius, GU376650, AY536367, P. B. bipinnatifida, Rouhan 155, Seychelles, GU376676, GU376530, P. B. crispatula, Wu et al. 361, Laos, GU376655, –, MO. B. fluviatilis, Carvalho 6457, Equatorial Guinea, GU376656, GU376510, US. B. gemmifera, Fay 1001, Sierra Leone, GU376657, GU376511, US. B. heteroclita, Huang 140, Taiwan, MK639322*, MK978740*, TAIF. B. heudelotii, Fay 1167, Sierra Leone, GU376662, GU376515, NY. B. humblotii, Razafitsalana & Torge 115, Madagascar, GU376663, GU376516, NY. B. lonchophora, Motley 2669, French Polynesia, GU376664, GU376517, NY. B. major, Fraser-Jenkins 1811, Nepal, GU376665, GU376518, US. B. portoricensis, McVaugh 18983, Mexico, GU376670, GU376523, NY. B. rhizophylla, Huang 169, Taiwan, MK639323*, MK978742*, TAIF. B. salicina, Fay 1185, Sierra Leone, GU376671, GU376525, US. B. scalpturata, Huang 164, Taiwan, MK639324*, MK978741*, TAIF. B. semipinnatifida, Steyermark 89173, Venezuela, GU376672, GU376526, US. B. serratifolia, Gutierrez 1014, Bolivia, GU376673, GU376527, NY. B. sinuata, Hoshizaki 1719, USA, GU376675, GU376529, NY. B. subcordata, Huang 106, Taiwan, MK639325*, MK978736*, TAIF. B. tibetica, Fraser-Jenkins 1782, Nepal, GU376677, GU376531, US. B. lianhuachihensis, Chao 3006, Taiwan, MK978746*, MK978747*, TAIF; Huang 115, Taiwan, MK639319*, MK978738*, TAIF; Y.-F. Huang 116, Taiwan, MK639318*, MK978737*, TAIF; Huang 172, Taiwan, MK639317*, MK978744*, TAIF. B. virens var. virens, Lu 19796, China, MK639326*, MK978745*, TAIF. Elaphoglossum lepervanchii, Rakotondrainibe 6359, Madagascar, AY540228, AY536323, P. Teratophyllum koordersii, Price 981, Philippines, GU376715, GU376566, US.
Figures S1–S4.
Data type: species data
Explanation note: Figure S1. Holotype of Bolbitis lianhuachihensis at TAIF (Y.-S Chao 3006). Figure S2 Holotype of Bolbitis hainanensis at PE (C. Wang 35870). Figure S3. Holotype specimen of Bolbitis virens var. compacta at L (Tagawa et al. 6802). Figure S4. Holotype of Bolbitis virens at K (Wallich 1033).