Jailoloa halmaherensis 知識
Solitary palm. Stem up to 12 m tall, 5 - 7 cm diam.; internodes 5 - 7 cm long, nodal scars conspicuous, dark brown. Leaves c. 9 in crown, 190 - 200 cm long including petiole; sheath tubular, 40 - 50 cm long and about 15 cm wide, tapering to 8 cm wide, greenish-brown; crownshaft up to 75 cm long; petiole 22 - 23 cm long, about 2 cm wide and 1.1 cm thick at the base; rachis arching; leaflets 25 - 26 on each side of the rachis; basal leaflets 55 - 75 cm long, 2.5 cm wide, pendulous rein up to 27 cm long, middle leaflets 44 - 48 cm long, 3.5 - 4 cm wide, apical leaflets 12.5 - 15 cm long, 0.3 - 1.2 cm wide; ramenta up to 3.5 cm long, 0.5 cm wide. Inflorescence up to 65 cm long at anthesis, with 18 - 20 primary branches including terminal rachilla; peduncle 10 - 15 cm long; prophyll c. 20 x 4 cm; complete peduncular bract c. 30 x 3 cm; the first order branches 35 - 45 cm long, about 10 - 13 branches (including terminal rachilla), 1 - 7 cm between branches; rachillae numerous, 7 - 12 cm long, each bearing 8 - 15 floral triads. Staminate flowers 5.5 x 2 mm in bud near anthesis, purple; sepals 3, free, c. 2.2 x 2 mm; petals 3, c. 4.5 x 2 mm; stamens c. 16, 2.5 - 4 mm long; filaments 1.75 - 2 mm long, dark brown; anthers 2.5 - 3 mm long; pistillode c. 2.5 x 0.1 mm. Pistillate flowers 6.5 x 6 mm at anthesis, purple; sepals 3.5 x 3.5 mm; petals 5 x 4 mm, purple with a thin line along the margin; staminodes inconspicuous; gynoecium 4.5 x 2.5 mm including stigma; ovule basal. Fruit 13 - 15 x 10 x 10 mm, epicarp purple when juvenile, becoming bright yellow or light orange when mature; pericarp c. 0.5 mm thick. Seed 10 x 8.5 x 7 mm; hilum up to 3 mm wide, embryo 2.5 x 1 mm.
Distinguished from other genera of subtribe Ptychospermatinae (tribe Areceae) by its slender, solitary habit, recurved leaves with ascending, narrow, leathery leaflets, inflorescence axes and flowers purple at anthesis, stamens c. 16, fruit orange-yellow when ripe with purple perianth cupule, thin, terete, straw-coloured endocarp with fine, longitudinal fibres, and the terete seed.
Critically Endangered. North Moluccas Province, Halmahera Timur Regency: Maba Town, PT. Buena Persada (Solway International) Nickel Mining Concession Area, Gunung Batu, path way back from camp D to the main camp, 00°42’50.6"N 128°06’02.6"E. Very steep terrain (more than 45°) on rocky outcrops or very poor soils in ultramafic heath forest at an elevation of 530 - 550 m above sea level. As noted by Heatubun (2011), this taxon appears to be adapted to the extreme conditions of ultramafic geology and soils that are thin or even absent. The ultramafic rocks have produced extremely weathered oxisol soils that are reddish yellow due to the high concentration of iron, magnesium and other metals, including nickel.
場所： Indonesia (0.727584°N, 128.188477°E)