Platycerium ridleyi Christ




Platycerium ridleyi Christ, Ann. Jard. Bot. Buitenzorg Suppl. 3: 8. 1909; Hennipman & Roos, Fl. Males., Ser. II, Ferns and Fern Allies 3: 142. 1998; Boonkerd & Pollawatn, Pterid. Thailand: 283. 2000. – Type: Ridley SFN 10830 (SING holo; P), Singapore.


Description from Hennipman & Roos, Fl. Males., Ser. II, Ferns and Fern Allies 3: 142. 1998.
Rhizome scales basifixed, 8–15 by 4–9 mm, index 1.5–2, widest near the middle, margin with flabelloid zone up to 3.5 mm wide and short hairs, apex rounded, midrib present. Fronds strongly dimorphic with nest leaves and fertile fronds. Nest leaves conspicuously stalked, green, appressed when old, 20–50 by 20–40 cm, margin entire, veins prominent. Foliage fronds maturing subsequently, asymmetrical, erect, 25–50 cm long or longer, with two unequal main lobes, one sterile, forked 4–6 times, one fertile, forked 4–7 times, with a central horizontal, stalked fertile patch. Hairs with 6–11 rays up to 1 mm long. Soral patch stalked 2–10 cm, obovate to elliptical, rarely bibbed or forked, 5–17 by 3–15 cm, sporangia with 10 or 11 indurated annulus cells, interspersed with receptacular paraphyses with 11–15 short-clavate rays. Spores 8 per sporangium .

Distribution in Thailand

PENINSULAR: Chumphon, Phatthalung.

Wider Distribution

Peninsular Malaysia, Sumatra, Borneo.


Epiphytic on trees high off ground at low altitude.

Proposed IUCN Conservation Assessment

Least Concern (LC). This species is widespread and not under any known threat.

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