Family

Hymenophyllaceae

Nomenclature

Vandenboschia maxima (Blume) Copel., Philipp. J. Sci. 67: 54. 1938; Ching, Fl. Reipubl. Popularis Sin. 2: 182. 1959; Tagawa & K.Iwats., SouthE. Asian Stud. 3(3): 73. 1965; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 44. 1967; Tagawa & K.Iwats., Acta Phytotax. Geobot. 23: 52. 1968. – Trichomanes maximum Blume, Enum. Pl. Javae: 228. 1828; Bedd., Suppl. Ferns Brit. Ind.: 10. 1892; Copel., Philipp. J. Sci. 51: 217, pl. 38, f. 1–4. 1933; Tardieu & C.Chr., Fl. Indo-Chine 7(2): 72. 1939; Holltum, Rev. Fl. Malaya ed. 1, 2: 107, f. 43. 1955 [‘1954’]; Tagawa & K.Iwats., Fl. Thailand 3: 83. 1979. – Crepidomanes maximum (Blume) K.Iwats., J. Fac. Sci. U. Tokyo, Sect. 3, Bot. 13: 531. 1985; Tagawa & K.Iwats., Fl. Thailand 3: 613. 1989; Boonkerd & Pollawatn, Pterid. Thailand: 71. 2000.

Description

Rhizome creeping, thick, 2 mm or more diam., densely covered with stiff dark brownish hairs when young. Stipes rather close to each other, stramineous, very narrowly winged in the upper part, hairy at base, 10–37 cm long. Laminae oblong-subdeltoid, acute at apex, one or two pairs of basal pinnae smaller than the next above forming round outline at base, 15–46 cm long, 10–24 cm wide, finely decompound to quadripinnatifid; rachis narrowly winged throughout, wings entire and flat; pinnae oblong subdeltoid to oblong-lanceolate, acute to acuminate at apex, unequally cuneate and stalked at base, larger ones 10(–14) cm long, 3(–4) cm wide; ultimate segments about 0.5–0.7 mm broad, at a narrow angle to the next larger division of the frond, round to moderately acute at apex, often curved inwardly; the wings of various axes narrower than the ultimate lobes, entire, flat. Sori on short axillary lobes usually near the pinna- or pinnule-rachis; involucre tubular, with short stalk and dilated mouth, narrowly winged, about 2 mm long, 0.7 mm diam., the mouth 1 mm or more diam.

Distribution in Thailand

SOUTH-WESTERN: Phetchaburi; PENINSULAR: Ranong, Surat Thani, Phangnga, Krabi, Nakhon Si Thammarat, Trang, Pattani, Yala.

Wider Distribution

In the tropics of E Asia and Polynesia.

Ecology

On moist muddy rocks or on wet sandy ground near streams in dense gloomy forest, rather common at various altitudes.

Proposed IUCN Conservation Assessment

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

Voucher specimens - Thailand

Middleton et al. 4799, Phetchaburi, Kaeng Krachan National Park (E); Williams 1893, Krabi (E).