1. Hapaline appendiculata Ridley

in J. Straits Branch Roy. Asiat. Soc. 49:47 (1908 ('1907')); Bogner in Pl. Syst. Evol. 144: 62 (1984). Type: Sarawak, Ridley 12411 (holotype SING!; isotype K!).

Slender, tuberous, evergreen perennial herb up to 20 cm high. Stem: tuber cylindric, 1.5 x 1 cm; stolon unknown. Roots c. 0.25 - 0.33 mm in diam. Leaf: prophyll linear, up to 9 x c. 4 mm, acute; cataphyll oblong-lanceolate to linear triangular or triangular, up to 10 cm x 5 mm, attenuate to acute; petiole 2.5 - 12 cm x 1 - 2 mm; leaf blade ovate to hastate to subsagittate, 10 - 16 x 3.5 - 6.5, coriaceous, light to dark green, occasionally with pale green diffuse markings, cm, margins smooth, apex acuminate, posterior lobes rounded to subacute, divergent to almost parallel, rarely absent. Inflorescence: 3 - 4 together; peduncle 4- - 10 cm x 0.25 - 0.5 mm; spathe 2 - 3 cm long; spathe limb elliptic, 1.6 - 2.6 cm x 5 - 7 mm, apex acute to briefly attenuate, base decurrent into lower spathe; lower spathe margins clasping, 4 - 8 x c. 1.5 mm; spadix 2.5 - 3.5 cm x 0.25 - 1 mm, free portion cylindric, up to 8 cm long, tapering apically into an greatly attenuated appendix composed of fused synandrodes. Flowers: synandria irregularly elongate in plan view, 2 - 3 x 0.5 - 1 mm; ovaries bottle-shaped, 1.5 x 0.7 mm, 2 - 3 in a single row; stigma capitate, c. 0.2 mm in diam., papillose; style very short. Infructescence: enclosed by the persistent lower spathe, 2 cm x 4 mm, few-berried; berries more or less globular, c. 4 mm in diam, stigmatic remains persistent, not prominent. (Fig. 1).

DISTRIBUTION. Malaysia (Sarawak). SARAWAK. 1st Division: Bau, Bidi, 6 Dec. 1905, Hewitt 476 (K (photo!), SING!). 7th Division: Belaga Distr., Punan Lusong to Long Jakah, 8 Sept. 1978, Burtt & Woods 11477 (E!); Puak, Sept. 1890, Ridley 12411 (holotype SING!; isotype K!).

HABITAT. In humus at path side on basalt. Hapaline appendiculata appears to be one of the rarest aroids in Borneo, with only four collections known to date. One of these, made by Anderson near Bau in the 1st Division of Sarawak, was later cultivated at Singapore Botanic Gardens and noted to have variegated leaves. Herbarium material of this collection was never prepared (Bogner 1984). Hapaline appendiculata is allied to H. celatrix in having evergreen coriaceous leaves and a terminal sterile appendix composed of fused synandrodes. In H. appendiculata this sterile appendix is greatly extended into a tail-like process. One of the cited collections (Hewitt 476) has ovate leaf blades lacking posterior lobes. Study of the inflorescences reveals no significent floral differences from typical H. appendiculata. Given the paucity of H. appendiculata collections I am not attaching any taxonomic significance to this vegetative variation.