Pyrrosia rasamalae (Racib.) K.H.Shing
Pyrrosia rasamalae (Racib.) K.H.Shing, Amer. Fern J. 73: 78. 1983; Hovenkamp, Fl. Males., Ser. II, Ferns and Fern Allies 3: 171. 1998; Boonkerd et al., Thai For. Bull. (Bot.) 32: 10. 2004. – Polypodium rasamalae Racib., Pteridoph. Buitenzorg: 99. 1898. – Type: Raciborski 83 (BO, K, L, M, P, US), Java.
Description from Hovenkamp, Fl. Males., Ser. II, Ferns and Fern Allies 3: 171. 1998.Rhizome 1–3 mm thick, long creeping, phyllopodia 1–5 cm apart, buds in the lower half of the internodes. Anatomy: vascular strands 4–8, sclerenchyma sheath distinct, sclerenchyma strands up to 10, scattered. Rhizome scales spreading, peltate, 4–9.5 by 0.4–1.4 mm, base entire, acumen ciliate, shining light brown or hyaline, rounded to ovate scales without acumen regularly present. Fronds simple, monomorphic, stalked, stipe 1–10 cm long, to 0.25(–0.5) x as long as the lamina, lamina 3.5–36 by 0.3–1.4 cm, base narrowed, widest at or below the middle, apex obtuse to acute. Venation: veins distinct, veinlets simple, free, excurrent. Hydathodes absent. Stellate hairs dimorphic, forming a dense mat, light brown, the straight rays boat-shaped to acicular, separate from the lower layer. Sori apical or all over the lamina, closely packed, 2 or 3 in a row in each creole, superficial, developing acropetally. Sporangia stalked, paraphyses not differentiated. Spores with irregular ridges and protuberances.
Distribution in Thailand
NORTHERN: Tak; SOUTH-WESTERN: Phetchaburi.
Proposed IUCN Conservation Assessment
Least Concern (LC). This species is widespread outside of Thailand and not under any known threat.
Voucher specimens - Thailand
Middleton et al. 1803, Phetchaburi, Kaeng Krachan (A, BKF).
Upper surfaces of fronds
Lower surfaces of fronds
Site hosted by the Royal Botanic Garden Edinburgh. Content managed by Stuart Lindsay, Gardens by the Bay, Singapore and David Middleton, Singapore Botanic Gardens. Last updated 24 January 2012