Bolbitis lianhuachihensis Y.S.Chao, Y.F.Huang, & H.Y.Liu, 2019

Chao, Yi-Shan, Huang, Yu-Fang, Dong, Shi-Yong, Huang, Yao-Moan & Liu, Ho-Yih, 2019, Bolbitis lianhuachihensis (Dryopteridaceae), a new species from Taiwan, PhytoKeys 131, pp. 69-81 : 74-75

Bolbitis lianhuachihensis Y.S.Chao, Y.F.Huang, & H.Y.Liu sp. nov. Fig. 1 and Suppl. material 1: Figures S1

Bolbitis virens var. compacta auct. non Hennipman: Knapp, Ferns Fern Allies Taiwan: 440. 2011.

Type.

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.

Description.

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.

Additional specimens examined.

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 Knapp 2011 1022-4 (HAST), 4 Dec. 2012, Pi-Fong Lu 24940 (TAIF), 23 Apr. 2006, Wei-Hsiu Wu s.n. (TAIF); Tiandi, 830 m a.s.l., 8 Aug. 2006, Ralf Knapp 20060806-18 (HAST, TAIF), 900 m a.s.l., 26 Sep. 2016, Yu-Fang Huang 172, 173, 174 (TAIF).

Distribution.

Taiwan ( Fig. 4 ).

Ecology.

Evergreen, broad-leaf forests, often near streams, below 1000 m a.s.l.

Etymology.

The specific epithet ' lianhuachihensis ' refers to the type locality.

Common name (assigned here).

Lian Hua Chih Shih Jyue (蓮華池實蕨; Chinese name).

Preliminary conservation assessment.

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 IUCN (2017) criteria.

Note.

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 ( Knapp 2011). However, based on our study, only B. hainanensis has coriaceous laminae, thicker than chartaceous laminar of B. lianhuachihensis and B. virens var. compacta . Moreover, B. lianhuachihensis has lanceolate sterile pinnae and very few free veinlets in areoles of sterile pinnae wider than 3.5 cm, differing from the two similar taxa.

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 ( Hennipman 1977; Moran et al. 2010a). We have applied several characters, including angles of veinlets to costae, free or anastomosing, row number of areoles between the costae and margins in sterile fronds and free veinlets in areoles or not for sterile fronds. We also found that venation patterns are more complicated, composed of multiple areoles, sub-areoles and free veinlets, which is also reported by Hennipman (1977). A character-state change from free venation to anastomosing venation is reported by Moran et al. (2010a). The venation characteristics in Bolbitis species are worthy of further investigation and application to the systematic and evolutionary study. To classify and describe the diverse venation morphology in detail would contribute to further studies of Bolbitis systematics.

Figures

Figure 1. Bolbitis lianhuachihensis A habit; note taller fertile fronds (photographed by Y. - S. Chao) B acrostichoid sori (photographed by P. - F. Lu) C venation of sterile frond (photographed by Y. - F. Huang).

Figure 4. Distribution of Bolbitis lianhuachihensis (black circles) in Taiwan.