Diplazium holttumii Hovenkamp (2019: 62)

Pongkai, Puttamon, Zhang, Li-Bing, Boonkerd, Thaweesakdi & Pollawatn, Rossarin, 2023, Revision of the fern genus Diplazium (Polypodiales: Athyriaceae) in Thailand, Phytotaxa 631 (1), pp. 1-69 : 26

9. Diplazium holttumii Hovenkamp (2019: 62) . Fig. 12 .

Diplazium malaccense C. Presl (1851:446) . nom. illeg. superfl., excluding syn. Asplenium sorzogonense C.Presl. – Athyrium malaccense Holttum, Rev. Fl. Malaya 2: 552 (1955 [‘1954’]).

Type: MALAYSIA. Malacca, H. Cuming 389 (lectotype PRC450315 !, designated by Holttum (1968); isolectotypes E00782179 !, K00044337 !, K000539990 !, K000539991 !, L3540651 , L3540653 , L3540652 , MO-104014 / / A: 1876167 !) .

Plants terrestrial. Stems erect, 3–5 cm diameter, scaly; scales 10–12 × 1.0– 1.5 mm, linear, concolorous, light brown, margin entire. Fronds 70–90 cm, pinnate, unipinnate-bipinnatifid; petioles 25–30 cm, 5–7 mm diameter, densly scaly at base, dark brown at base. Laminae 55–60 × 20–25 cm, terminal pinna not distinct, oblong in outline, apex long acuminate, glabrous, papyraceous, deep green; lateral pinnae 20–30 pairs, alternate, 12–15 × 2.0– 2.5 cm, gradually becoming smaller upwards, oblong, apex long acuminate, base subtruncate; lobed at margin; lobes 2/3 way to midrib of pinnae, about 5 mm wide, apex round or obtuse, margin subentire, stalked; stalks 1–2 mm; veins pinnate, 4–5 pairs, free. Sori 2–3 mm, narrowly-oblong, indusiate; indusia linear, persistent. Spores monolete, 32.5–35.0 × 20.0–22.5 μm, bilateral, concavo-convex to plano-convex, perispore present; ornamentation prominent wing folds.

Thailand: —PENINSULAR: Ranong (Khao Por Ta Luang Kaew), Surat Thani (Ban Don), Nakhon Si Thammarat (Khao Luang), Trang (Khao Chong, Phu Pha Mek), Songkhla (Ton Nga Chang), Yala (Ban Mae Prik) .

Distribution: — Indochina to Indonesia.

Ecology: —On mountain slopes in dense evergreen forests at medium elevations.

Specimens Examined:— THAILAND. Songkhla, Ton Nga Chang, C. Kraithep 24 (PSU); Trung, Phu Pha Mek, D.J. Middleton et al. 2029 (BKF); Nakhon Si Thammarat, Khao Luang, P. Pongkai 122 (BCU); Ranong, Khao Por Ta Luang Kaew, T. Boonkerd 1473 (BCU). INDONESIA. No locality, A.J.G.H. Kostermans 6099 (K); Sulawesi, E Hennipman 5744 (K); Sumatra, E. Gardette 306 (K); ibis., E. Gardette 461 (K); Kalimantan, J.S. Burley & Tukirin 3255 (K); Kalimantan, K. Iwatsuki, G. Murata, Jdransfield & Saerudin B2472 (K); Sumatra, K. Iwatsuki, G. Murata, Jdransfield & Saerudin S845 (K); no locality, K. Ueda & D. Darnaedy B8982 (K); Kalimantan, Kato, M.; Murata, G.; Mogea, Y.P. (K). MALAYSIA. Selangor, A.A. Samut 148 (K); Malacca, A.C. Maingay 3233 (K), Johore Mt. A.G. Piggott 1773 (K); Negri Sembilan Gunong Telepak Burok, A.G. Piggott 1912 (K); Pahang, A.G. Piggott 2495 (K); Sabah, B.S. Parris 11365, (K); Negri Sembilan Pasoh Forest Reserve, B.S. Parris & P.J. Edwards 10560 (K); Pahang, B.S. Parris 10599, (K); ibis., B.S. Parris 10960 (K); Sabah, B.S. Parris 11327 (K); Sarawak, B.S. Parris 6510 (K); Penang, C. Curtis 999 (K); Penang, C. Gaudichaud-Beaupré 13 (K); Perak, C.G. Matthew s.n. (K); Negri Sembilan Bukit Putis, E.S. Hose & G. Hose 174 (K); Negri Sembilan Gunong Angsi, E.S. Hose & G. Hose 4811 (K); Sarawak, G.F. Hose 330 (K); Perak, G.F.Hose s.n. (K); Malacca, H. Cuming 389 (K); ibis., H. Cuming 390 (K); Perak, H.C. Robinson s.n. (K); Perak, J. Sinclair SFN38674 (K); Langkawi, Jaman, R.; Hamid s.n. (K); Pahang, K.M. Kochummen 85251 (K); Perak, L. Wray 1199 (K); Selangor, L.W. Lee UL38 (K); Negri Sembilan Gunong Angsi, M. Nur 11563, (K); Negri Sembilan Ulu Rembau, M. Nur s.n. (K); Selangor, M.E.D. Poore 138 (K); Penang, N. Wallich 205 (K); ibis., N. Wallich s.n. (K); Perak, N.H. Ridley 7271 (K); Pahang, Native Collector 5818, (K); Penang R.E Holttum SFN31196 (K); Malacca, R.E. Holttum 9685 (K); Penang, W. Norris s.n. (K); Johore Mt. Wight 161 (K). SINGAPORE. Reservoir woods, N.H. Ridley 12562 (K).

Figures

FIGURE 12. Diplazium holttumii Hovenkamp. A, lamina. B, a part of pinna with sori. C, scale showing entire and not black marginal cells. T. Boonkerd 1473 (BCU).