Drynaria bonii Christ

Etymology

Named after Henry Francois Bon who collected the type specimen of Drynaria bonii in Vietnam in 1886.

Family

Polypodiaceae

Nomenclature

Drynaria bonii Christ, Not. Syst. 1: 186. 1910; Tardieu & C.Chr., Fl. Indo-Chine 7(2): 517, f. 61. l & 61.2. 1941; Holttum, Dansk Bot. Ark. 20: 20. 1961; Holttum, Dansk Bot. Ark. 23: 231. 1965; Tagawa, J. Jap. Bot. 38: 329. 1963; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 58. 1967; Tagawa & K.Iwats., Fl. Thailand 3: 545. 1989; Hovenkamp & Roos, Fl. Males., Ser. II, Ferns and Fern Allies 3: 36. 1998; Boonkerd & Pollawatn, Pterid. Thailand: 249, 268. 2000; Newman et al., Checkl. Vasc. Pl. Lao PDR: 29. 2007. – Type: Bon 3204 (P), Tonkin.

Description

Rhizome short creeping, tightly fixed on substrate, sometimes very flat, 1–2.5 cm wide, 3–5 mm thick, densely scaly; scales oval with long tails, peltate, round at base, up to 2.5 mm long with tails of about 2 mm in length, 1.5 mm broad, sharply toothed to fimbriate at margin, bi-coloured with black brown small central portion and brown margin. Nest-leaves many, imbricate, covering rhizome almost entirely, oval in outline, deeply cordate at base, subentire, 5–10 by 4.5–7 cm. Foliage-leaves: stipes stramineous, 10–25 cm long, narrowly winged almost to the base, scaly at base; laminae pinnatifid nearly to rachis, decurrent laminae less than 5 mm in breadth, 30–55 by 20–40 cm; lobes more or less ascending, oblanceolate or oblong-lanceolate, moderately acute to caudately acuminate, 10–22 by up to 3.8 cm, subentire, more or less narrowed towards base; veins distinct on both surfaces, finely anastomosing with 4–6 rows of areoles between main veins; chartaceous, light green, glabrous. Sori round or punctiform, in 2–4 irregular rows between main veins.

Distribution in Thailand

NORTHERN: Mae Hong Son, Chiang Mai, Chiang Rai, Lampang, Phrae, Tak, Phitsanulok; NORTH-EASTERN: Loei, Nong Khai; EASTERN: Chaiyaphum, Nakhon Ratchasima; SOUTH-WESTERN: Uthai Thani, Kanchanaburi, Prachuap Khiri Khan; CENTRAL: Sing Buri, Saraburi; SOUTH-EASTERN: Prachin Buri, Chon Buri.

Distribution in Laos

Champasak.

Distribution in Cambodia

Pursat, Siem Reap, Takeo

Wider Distribution

China (Guizhou) and Indochina.

Ecology

On dry or muddy rocks and tree trunks, rarely terrestrial, in light shade or in dense deciduous forests at low to medium altitudes, less than 1000 m, fairly common.

Proposed IUCN Conservation Assessment

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

Voucher specimens - Thailand

Middleton et al. 5133, Loei, Phu Suan Sai, Tat Huang waterfall (E).

Voucher specimens - Laos

Maxwell 98-877, Champasak (CMU)

Voucher specimens - Cambodia

Long et al. CL225, Siem Reap (P).

Habit

Habit

Rhizome

Rhizome

Cross section of rhizome

Cross section of rhizome

Young nest leaves

Young nest leaves

Old dry nest leaves

Old dry nest leaves

Scales

Scales

Growing tip and young scales

Growing tip and young scales

Stipe

Stipe

Frond upper surface

Frond upper surface

Old Sori

Old Sori

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 16 November 2016.