Araceae (PDF)

ARACEAE 33(articulation) thickened, 1–2.5 × 0.3–1 mm; stigma pale yellowishor dirty brownish, variable, usually distinctly broaderthan style diam., disciform to subhemispheric, more rarelysuperficial, punctiform, orbicular or oval in outline, with a shallowcentral depression to clearly 2-lobed, verrucate; lobesrounded, 0.4–0.6 mm high, 0.6–1.2 mm in diam.; male zoneconic or fusiform-cylindric, rarely obconic, sometimes (partly)laterally compressed, 1–4 × 0.6–3.5 cm, flowers congested;male flowers consisting of 3–5 stamens; stamens 3–3.5 mm;filaments 0.5–2 mm, basally or up to 2/3 of length connate;anthers creamy white, 1.5–3 × 1–2 mm; connectives flat or witha ridgelike extension, perpendicular to long axis, either small orvery large, maroon or dark brown; pores apical, elongate; appendixovoid, conic, or triangular-ovoid, rarely subcylindric,inflated or strongly laterally compressed, 3–11 × 1.5–5 cm,glabrous or verruculose, rarely entirely echinate, often with afew longitudinal shallow or deep, broad folds, or irregularlyfolded throughout, base strongly truncate, apex obtuse, rarelyacute, usually with a few broadly conic staminodes. Infructescencecylindric or subglobose, 4–11 × 3.5–5 cm, dried malezone and appendix often remaining, as well as dried spathe.Berries 1- or 2-seeded, at first green, at maturity turning blueand finally violet, at apex with dried style and stigma remaining.Fl. Apr–May.Shaded places in primary evergreen or mixed evergreen/deciduousforests, on metamorphic bedrock, in rich soils, or secondary forests,thickets, forest margins; 100–3300 m. Guangxi, Guizhou, Yunnan[Laos, N Thailand, N Vietnam].17. ARUM Linnaeus, Sp. Pl. 2: 964. 1753.疆 南 星 属 jiang nan xing shuLi Heng ( 李 恒 Li Hen); Peter C. BoyceHerbs, tuberous. Cataphylls several. Leaves 2, simple; petiole sheathing; leaf blade hastate-sagittate or sagittate. Inflorescences1(or 2), pedunculate; peduncle long or short. Spathe ultimately marcescent, convolute, base (tube) separated from limb by a constriction;spathe tube oblong or ovate; limb initially erect, cymbiform, concave or arched, later flopping forward or actively reflexing,ovate-lanceolate to oblong-lanceolate. Spadix sessile, shorter than to subequaling spathe; flowers unisexual, naked; female zonecylindric; ovary oblong, 1-loculed; ovules few on 2 or 3 parietal placentae; stigma sessile; sterile flowers (staminodes) usuallypresent between female and male zones and also above male zone; appendix dark purple or yellow, cylindric-conic, cylindric, orclavate; male zone shorter; stamens 3 or 4, nearly tetragonal, short; connective convex; anthers obovoid, shorter than filaments,opening by an apical pore or longitudinal slit; sterile flowers broadly conic, filiform, ± thickened, verrucose, these between femaleand male zones recurved, those at distal part of male zone reflexed upward. Berries obovoid, few seeded. Seeds with endosperm;embryo axile.Twenty-eight species: N Africa, SW Asia extending to C Asia, Europe; one species in China.1. Arum jacquemontii Blume, Rumphia 1: 118. 1836.疆 南 星 jiang nan xingArum griffithii Schott.Herbs, tuberous, sprouting in late autumn from a disciform,vertically oriented tuber 2–5 cm in diam., 2–2.5 cm thick.Petiole mid-green, stained dull purple, terete, 10.5–28 cm ×2.5–4.4 mm. Leaf blade dark to mid-green, sagittate to sagittate-hastate,11–30 × 4–12 cm, apex acute. Inflorescence notscented; peduncle exceeding leaves, pale green proximally, deepgreen distally, terete, 11–32 cm × 5–7 mm. Spathe 12–22 cm;tube outside green, inside white, oblong-cylindric, 2.5–4 × 1.2–1.6 cm, slightly constricted apically; limb erect at first but soonflopping forward, outside mid-green with faint purple staining,inside dull purple, deeper purple along middle, paler proximally,brownish purple to purple distally, narrowly lanceolate,9–18 × 1–3 cm, acuminate. Spadix 2/3–3/4 as long as spathelimb, 9–20 cm in total length; female flowers in an oblongcylindriccluster 15–17 × 5–6 mm; ovary pale greenish yellow,oblong, 2–3 mm; stigma pale grayish mauve; pistillodes in 3 or4 whorls forming a zone 3–4 mm; bristles glossy deep violet,subulate-filiform, 3–4.5 mm; bases dark purple, bulbiform, verrucate;staminodes in 2 or 3 whorls forming a zone 3–5 mm;bristles flexuose, glossy deep violet, filiform, 2–2.5 mm; basesdark purple, barely conic, verrucate; interstices: proximal 2.5–3mm cream-colored, longitudinally ridged; distal 1.5–2 mmcream-colored, smooth; appendix dull yellow to orange-brown,purple, or brownish purple, base paler, cylindric, taperingbasally, 6–17 cm × 3–7 mm; male flowers in an oblong zone 6–7 × 4–5 mm; anthers and connectives maroon. Infructescencecylindric, 4–4.5 × 1.8–2.2 cm. Berries oblong, 4–9 × 3–4 mm.Fl. Apr–May.Among rocks in damp soil pockets and crevices, occasionallyalong damp field edges; 1600–3700 m. SW Xinjiang, W Xizang [NAfghanistan, N India, Kashmir, W Nepal, N Pakistan, Tajikistan, ETurkmenistan, SE Uzbekistan; SW Asia (NE Iran)].Arum jacquemontii has a wide distribution, occurring from the NEcorner of Iran to the W Himalayas (Boyce, Gen. Arum, 139, map 17.1993). Arum korolkowii Regel as reported in FRPS (13(2): 100–101.1979) is, in fact, A. jacquemontii. Although similar to A. korolkowii, A.jacquemontii is readily distinguished by its dull purple, not striped,petioles, the purple spathe limb, longer spadix appendix, and purple, notgreen, staminode and pistillode bases. Further, the pollen exine of A.jacquemontii is spinulose and not scabrous as in A. korolkowii. Animportant geographic difference is that A. jacquemontii grows farthersouth and east and at higher elevations than A. korolkowii.