Family

Polypodiaceae

Nomenclature

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

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.

Wider Distribution

Malesia.

Ecology

Epiphytic in primary evergreen forest. In bamboo thicket.

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).