taxonID	type	description	language	source
E078202E28304718AE85520EFD6FF8EB.taxon	materials_examined	Type: — VIETNAM. Nghean Province: Pumat National park, elev. 350 m, 29 October 2014, Li Bing Zhang, Liang Zhang & Ngan Thi Lu 7189 (holotype VNMN!, isotypes CDBI!, MO!). Diagnosis: — This species resembles Arachniodes chinensis (Rosenstock 1914: 30) Ching (1962: 257) by having laminae 2 - pinnate and deltoid, pinnae slightly oblique deltoid to lanceolate, and pinnules lanceolate or oblong, but the former has rhizomes ascending, lamina apex caudate, with a conform terminal pinna, sori closer to the segment margins than to the midrib, and indusia ciliate; in contrast, the latter has rhizomes creeping, lamina apex acuminate, sori medial between midvein and margin or closer to midvein, and indusial often entire. Rhizome erect, ascending, small, ca. 1.5 × 1.0 cm, with remnant bases of old stipes, 5 – 7 fronds in one plant; ca. 15 roots, 2 – 14 cm × 1.6 mm, apex densely scaly; scales fragile often break, brown to dark brown, filiform to lanceolate, 1.6 – 8 × 0.4 – 1.0 mm, entire, membranous. Frond 22 – 66 cm, stipe 14 – 34 cm × 4 – 8 mm, base densely scaly with scales similar to those on rhizome, upward scales appressed, filiform-linear, 1.0 – 8 × 0.3 – 0.8 mm, but blackish, thicker, based or round attached with upper part entire, lower part margin sparse hairlike or irregular denticulate. Lamina 2 - pinnate, often longer than stipe, dull green when dried, deltoid somewhat as triangular or deltoid-lanceolate, 8 – 32 × 9.5 – 23 cm, thinly papery to papery, base cordate, rounded-truncate, or broadly cuneate, apex abruptly caudate with a stalked conform terminal pinna, apex very long up to 20 cm and bigger than lateral pinnae (larger any pinnae); rachis abaxially and adaxially scaly as distal portion of stipe scales; pinnae 1 – (2) – 3 – (4) pairs, lowest pinnae lanceolate, 5 – 13 × 2.2 – 5 cm, alternate, lower 1 (or 2) pairs opposite with short stalk 0.2 – 0.5 cm, base cordate, rounded-truncate, or broadly cuneate, apex acuminate; pinnules 6 – 14 pairs, very short stalked or sessile, lanceolate or oblong, 2.5 × 1.4 cm, base acroscopically rounded, broad cuneate (broad acute), obtuse, basiscopically cuneate, apex acute or obtuse, margin mucronate or aristate; costule, veins of ultimate segments with minute brown linear-subulate appressed scales abaxially. Sori, 2.8 – 4 mm, terminal on veinlets, 2 – 11 pairs per ultimate segment, close to margin; spores subglobose to elliptical type, 31 – 36 × 43 – 45 um, inflated, irregular echinate folder; indusia, 1.2 – 2.4 mm, dark brown, firmly membranous, subentire, long ciliate as hairlike.	en	Lu, Ngan Thi, Zhang, Liang, Zhou, Xin-Mao, Gao, Xin-Fen, Zhang, Li-Bing (2018): Three new species of the fern genus Arachniodes (Dryopteridaceae) from Vietnam. Phytotaxa 376 (3): 126-132, DOI: 10.11646/phytotaxa.376.3.1, URL: http://dx.doi.org/10.11646/phytotaxa.376.3.1
E078202E28304718AE85520EFD6FF8EB.taxon	etymology	Etymology: — The specific epithet refers to long caudate apex of the species	en	Lu, Ngan Thi, Zhang, Liang, Zhou, Xin-Mao, Gao, Xin-Fen, Zhang, Li-Bing (2018): Three new species of the fern genus Arachniodes (Dryopteridaceae) from Vietnam. Phytotaxa 376 (3): 126-132, DOI: 10.11646/phytotaxa.376.3.1, URL: http://dx.doi.org/10.11646/phytotaxa.376.3.1
E078202E28304718AE85520EFD6FF8EB.taxon	distribution	Distribution: — This species is currently known from North-Central Vietnam. Notes: — Arachniodes longicaudata morphologically also resembles A. yaoshanensis (Y. C. Wu 1932: 78) Serizawa (1973: 219) by having long caudate lamina apex, lowest pinnae not elongated, but the former has fewer pinnae sometimes lamina triangular, scales not blackish, and sori closer to segment margins. Phylogenetically, A. longicaudata was resolved as sister to A. nigrospinosa (Ching 1931: 191) Ching (1962: 258) whose type is from Guangdong, China (Lu et al., submitted). Arachniodes longicaudata is not rare in Vietnam and can be found in the North (Bavi, Langson, Tamdao) and in the Central (Nghean, Quangbinh, Quangtri) Vietnam.	en	Lu, Ngan Thi, Zhang, Liang, Zhou, Xin-Mao, Gao, Xin-Fen, Zhang, Li-Bing (2018): Three new species of the fern genus Arachniodes (Dryopteridaceae) from Vietnam. Phytotaxa 376 (3): 126-132, DOI: 10.11646/phytotaxa.376.3.1, URL: http://dx.doi.org/10.11646/phytotaxa.376.3.1
E078202E28304719AE85577AFAA7FB08.taxon	materials_examined	Type: — VIETNAM. Quangnam Province: Songthanh Nature reserve, elev. 400 – 460 m, 5 December 2014, Li Bing Zhang, Liang Zhang & Ngan Thi Lu 7926 (holotype VNMN!, isotypes CDBI!, MO!). Diagnosis: — This species resembles Arachniodes dimorphophylla (Hayata 1911: 428) Ching (1962: 257) in having fronds dimorphous, fertile fronds lanceolate, longer but narrower than sterile fronds, sterile fronds ovate-lanceolate, and sori small (1.5 – 2 mm in diam.) and closer to midribs than to segment margins, but the former bears rhizomes suberect or ascending (creeping rhizomes unseen), laminae more shallowly dissected, often 2 - pinnate-pinnatifid, basal basiscopic segments of lowest pinnae less elongated, and indusia ciliate; in contrast, the latter has rhizomes often short-creeping, laminae 3 - pinnate, basal basiscopic segments of lowest pinnae longelongated, and indusia entire. Rhizome erect or ascending, 1.2 – 4.2 × 1.2 – 2.5 cm, with remnant bases of old stipes, up to 18 fronds each rhizome; ca. 35 roots, 3 – 10 cm × 0.3 – 0.7 mm, apex densely scaly; scales (brown to red-brown), linear-narrow lanceolate, tip tortuous, 4 – 10 × 0.3 – 1.0 mm, entire, membranous. Fronds dimorphic, 21 – 75 cm. Sterile lamina 14 – 32 × 5 – 18 cm, stipe 7 – 29 cm × 3.2 – 12 mm, base with scales similar to those on rhizome, scales sparser upward, blackish, thread – linear, 4 – 6 × 0.12 – 0.6 mm, entire and thicker; lamina 2 pinnate-pinnatifid, green when dried, deltoid-lanceolate, papery, base acute, apex acuminate; rachis scaly as distal portion of stipe, sparse scales adaxially; pinnae 12 – 22 pairs, lowest pinnae 4 – 14 × 2 – 5.5 cm, stalks ca. 0.7 cm, upper shorter even sessile, alternate, spreading, lanceolate or deltoid-lanceolate, base rounded or broadly cuneate, apex acute or obtuse; pinnules 5 – 14 pairs per pinna, shortly stalked, oblong, deltoid-lanceolate, sometimes elliptical-oval, 1.0 – 1.5 × 1.5 – 3.8 cm, base acroscopically rounded, obtuse, cuneate basiscopically cuneate, apex obtuse, margin often aristate; costule, vein sparse minute brown filiform scales abaxially. Fertile fronds up to 75 × 4 – 12 cm; lamina similar to that of sterile fronds in shape and dissection, often longer than sterile but narrower, papery to subleathery; pinnae 12 – 24 pairs, lowest pinnae 4 – 11.2 × 1.8 – 3.2 cm, lanceolate, alternate, base acute, oblique-cordate, apex acute or acuminate; pinnule 8 – 13 pairs, lanceolate or oblong, 0.5 – 1.0 × 1.0 – 2.8 cm, base acroscopically truncate, obtuse, basiscopically cuneate, apex obtuse, margin lobed or pinnatifid, mucronate teeth. Sori small (ca. 2.0 mm), terminal on veinlets, approximate, 2 – 9 pairs per ultimate segment, closer to midvein than margin; spores elliptical type, 31 – 38 × 35 – 46 um, inflated, echinate folder; indusia brown to dark brown, membranous, ciliate or irregularly denticulate on margin (ca. 2.4 mm).	en	Lu, Ngan Thi, Zhang, Liang, Zhou, Xin-Mao, Gao, Xin-Fen, Zhang, Li-Bing (2018): Three new species of the fern genus Arachniodes (Dryopteridaceae) from Vietnam. Phytotaxa 376 (3): 126-132, DOI: 10.11646/phytotaxa.376.3.1, URL: http://dx.doi.org/10.11646/phytotaxa.376.3.1
E078202E28304719AE85577AFAA7FB08.taxon	etymology	Etymology: — From quangnam, the province name in central Vietnam, and the Latin ending - ensis, of origin, referring to the type locality where we collected the plant.	en	Lu, Ngan Thi, Zhang, Liang, Zhou, Xin-Mao, Gao, Xin-Fen, Zhang, Li-Bing (2018): Three new species of the fern genus Arachniodes (Dryopteridaceae) from Vietnam. Phytotaxa 376 (3): 126-132, DOI: 10.11646/phytotaxa.376.3.1, URL: http://dx.doi.org/10.11646/phytotaxa.376.3.1
E078202E28304719AE85577AFAA7FB08.taxon	distribution	Distribution: — This species is currently only known from the type locality and probably is endemic to Central Vietnam. Notes: — In addition to Arachniodes quangnamensis, there are two more species in the genus with dimorphic fronds: A. hainanenis (Ching 1934: 44) Ching (1962: 258) (type: Hainan, China) and A. dimorphophylla (type: Okinawa, Japan). Phylogenetically, A. quangnamensis was resolved as sister to A. hainanensis, while the Japanese dimorphic species was nested in other clade (Lu et al., submitted). He et al. (2013) noted a dimorphic species reported from Taiwan, which needs to be confirmed. Additional material examined: — VIETNAM. Quangnam Province: Songthanh Nature Reserve, elev. 400 – 460 m, 5 December 2014, Li Bing Zhang, Liang Zhang & Ngan Thi Lu 7915, 1918 (CDBI!, MO!, VNMN!).	en	Lu, Ngan Thi, Zhang, Liang, Zhou, Xin-Mao, Gao, Xin-Fen, Zhang, Li-Bing (2018): Three new species of the fern genus Arachniodes (Dryopteridaceae) from Vietnam. Phytotaxa 376 (3): 126-132, DOI: 10.11646/phytotaxa.376.3.1, URL: http://dx.doi.org/10.11646/phytotaxa.376.3.1
