Davallia heterophylla J.E. Smith, 1793
Description
Rhizome without the scales 1.8-2.4 mm in diametre, white waxy under the scales (D. heterophylla Rhizome). Scales red-brown with pale border quickly diminishing or disappearing towards the apex, narrowed evenly towards the apex or flat and nearly acicular and narrowed abruptly from a broad base, curling backward (or appressed to rhizome, not crisped - only in the Pacific and New Guinea), not bearing multiseptate hairs, with marginal setae at least in distal part, peltate, 5-7 mm long by 0.5-0.6 mm broad. Stipes pale, adaxially grooved or not, 0.5-7 cm long, glabrous or with few scales. Lamina simple (D. heterophylla Habitus), one entire to pinnatilobed leaf bearing multicellular hairs or glabrous, strongly dimorphous. Sterile lamina narrowly ovate (or ovate), 5-20 cm long by 20-45 mm broad, margin flat or nearly so, not distinctly crenulate even towards apex. Fertile lamina linear or rarely pinnatifid, 4-16 cm long by 5-25 mm broad. False veins not present. Sori separate at the forking point of veins. Indusium attached at the broad base and hardly or not at the sides, semicircular, wider than long, 1 mm long by 1.5-2.5 mm broad, upper margin not elongated, truncate or slightly rounded, separated from or even with lamina margin (D. heterophylla SEM, picture of indusia).
Distribution
Continental Asia: India (Northern Nicobar Islands 1 coll.); Peninsular Thailand (8 coll.); Cambodia (1 coll.); Southern Vietnam (Poulo Condore 3 coll.).
Malesia: Sumatra (many coll.); Malay Peninsula (many coll.); Java (many coll.); Lesser Sunda Islands (Flores 1 coll.); Borneo (many coll.); Philippines (Balabac Island 1 coll., Paragua Island 1 coll., Luzon 10 coll., Polilo Islands 3 coll., Catanduanes 1 coll., Leyte 1 coll., Samar 1 coll., Mindanao, Mt. Urdaneta 1 coll.); Sulawesi (Southern, Lake Matano 1 coll., Minahasa 1 coll.); Moluccas (Ambon 2 coll., Seram 1 coll., Aru Islands, P. Kobroor 1 coll., Banda 1 coll.); New Guinea (many coll.).
Pacific: Palau Islands (1 coll.); Admiralty Islands (1 coll.); Bougainville (3 coll.); Solomon Islands (5 coll.); New Caledonia (1 coll.); Carolines (3 coll.); Marianas (Guam 4 coll.); Fiji (11 coll.); Tonga (1 coll.); Samoa (many coll.).
Ecology
Epiphytic or epilithic, sometimes in swamp forest. Altitude 0-900 (-2100, once recorded, Mt. Kaindi in Papua New Guinea).
Note
The presence of appressed scales in some collections in the New Guinea and in the Pacific seems to have no ecological base. They occasionally occur between normal collections. As there are no other differences I refrain from separating the collections with appressed scales taxonomically.