e-Flora of Thailand
Volume 11 > Part 2 > Year 2012 > Page 281 > Araceae > Rhaphidophora
16. Rhaphidophora sylvestris (Blume) Engl.
in A.DC. & C.DC., Monogr. Phan. 2: 239. 1879; Engl. & Krause in Engl., Pflanzenr. IV, 23B (Heft 37): 22–25, fig. 6. 1908 (‘silvestris’); Ridl., Fl. Malay Penins. 5: 122. 1925; Boyce, Gard. Bull. Singapore 51: 243–247, fig. 16. 1999.— Calla sylvestris Blume, Catalogus: 62. 1823.— Scindapsus sylvestris (Blume) Kunth, Enum. 64, Pl.3. 1841.
Accepted Name : This is currently accepted.
Synonyms & Citations :
Description : Medium to large, occasionally very large, moderately robust, leptocaul to semipachycaul, homeophyllous secondary hemiepiphyte to 20 m. Stems smooth, climbing stems rectangular in cross-section, the angles often slightly winged and surfaces between slightly concave, free stems rectangular to sub-terete in cross-section, green, later mid-brown, without prophyll, cataphyll and petiolar sheath fibre. Leaves distichous on adherent and free shoots, those distal on flowering shoots densely so; petiole deeply grooved adaxially, 1–8.5 by 0.15–0.3 cm, smooth, apical and basal pulvini weakly defined; petiolar sheath very prominent, extending to and encircling the apical pulvinus, briefly ligulate, very soon drying and falling to leave a continuous conspicuous scar from the petiole base, around the top of the apical pulvinus and back to the base; leaf blade entire, lanceolate-elliptic to falcate-lanceolate, slightly to markedly oblique, 4.5–32 by 1.75–8.5 cm, thinly coriaceous, upper surfaces slightly glossy, lower surfaces semimatte, base sub-acute to briefly truncate, apex acute to slightly attenuate, with a prominent apiculate tubule; midrib slightly raised abaxially, slightly sunken adaxially; primary venation pinnate, slightly raised abaxially and adaxially; interprimaries parallel to primaries and only slightly less prominent, very slightly raised abaxially and adaxially; secondary and tertiary venation ± obscure in fresh material, visible as a faint reticulum in dried specimens. Inflorescence solitary, subtended by a fully developed foliage leaf; peduncle compressed-cylindrical, 2–8.5 by 0.15–0.5 cm; spathe narrowly elliptic, very shortly, stoutly beaked, 4.5–7.5 by 1–3 cm, thinly but stiffly fleshy, dull yellow at anthesis, paler internally, soon falling; spadix weakly clavate-cylindrical, sessile, inserted ± level on peduncle, 3–6 by 1–2.5 cm; stylar region mostly rhombohexagonal, 1–2 by 1.5–2 mm, truncate; stigma punctiform, raised, ca 0.25–0.3 mm diam.; anthers exserted at anthesis. Infructescence 6–8 by 2–2.5 cm.
Thailand : PENINSULAR: Phangnga, Nakhon Si Thammarat.
Distribution : Peninsular Malaysia (type of Rhaphidophora wrayi), Sumatra, Java (type and type of R. ligulatus), Lesser Sunda Islands, throughout Borneo (types of R. gratissima and R. motleyana), and the Moluccas (type of R. aruensis).
Ecology : Perhumid to wet lowland, hill to sub-montane forests; 100–1,400 m alt.
Vernacular : Ta khap (ตะขาบ)(Peninsular).
Notes: Rhaphidophora sylvestris is most similar to R. montana and R. crassifolia. From R. montana it may be distinguished by the narrower leaves, the lack of shoot tip fibre and by the shorter, clavate-cylindrical spadix (3.5–6 cm vs 9–16 cm in R. montana). Overall R. crassifolia is very similar in appearance but may be readily identified by the considerably thicker leaves, especially notable in dried specimens, and the twisted primary adherent stem.