Gamblea, C. B. Clarke

Shang, C. - B., Lowry Ii, Porter P. & Frodin, David G., 2000, A taxonomic revision and re-definition of the genus Gamblea (Araliaceae), Adansonia (3) 22 (1), pp. 45-55 : 47-48

GAMBLEA C.B. Clarke

In J.D. Hook., Fl. Brit. Ind. 2: 739 (1879); Hutch., Gen. Fl. Pl. 2: 78 (1967); J.C. Grierson, Fl. Bhut. 2: 340 (1991).

— Type: Gamblea ciliata C.B. Clarke.

Evodiopanax (Harms) Nakai, J. Arnold. Arbor. 5: 7 (1924); Ohwi, Fl. Jap.: 834 (1953); S.Y. Hu, J. Arnold Arbor. 61: 111 (1980); C.-B. Shang & J.-Y. Huang, J. Nanj. Forest. Univ. 17: 32 (1993). — Acanthopanax sect. Evodiopanax Harms, Mitt. Deutsch. Dendr. Ges. 27: 28 (1918); Li, Sargentia 2: 88 (1942); Hoo & Tseng, Fl. Reipub. Popul. Sin. 54: 106 (1978); C.-B. Shang, Fl. Sylv. Sin. 2: 1785 (1985). — Lectotype: Evodipanax innovans (Seib. & Zucc.) Nakai [= Gamblea innovans (Seib. & Zucc.) C.-B. Shang, Lowry & Frodin ], designated by Hutchinson, Gen. Fl. Plants 2: 71 (1967).

Unarmed shrubs or trees, with both long and short shoots; cataphylls linear, with evident parallel veins, caducous. Leaves palmately compound, (1-)3-5-foliolate, leaflets sessile or with short petiolules, margins subentire to serrulate, usually with ciliate-hispid teeth, abaxial surface with domatia in the axils of the secondary veins, petiolule slightly expanded and sheathing at the base, without stipules. Inflorescences terminal on short shoots, simple or more often compound umbels or panicles of umbellules, often with 1-2 lateral umbellules borne on the larger of the primary axes; pedicels unarticulated; calyx rim subentire or 4-5-toothed; petals 4 or 5, valvate; stamens 4 or 5, anthers ovoid; disk flat to conical; ovary 2- 4(-5)-carpellate; styles 2-4(-5), free or united for most of their length. Fruit elliptic to globose or slightly obloid, sometimes laterally compressed, pyrenes 2-4(-5), endosperm smooth.

As circumscribed here, Gamblea is a genus of four species, extending from the eastern Himalayas to SE and E Asia, including Japan, and S to the peninsular Malaysia and northern Sumatra.

All four species of Gamblea have domatia in the axils of the secondary veins on the abaxial surface of their leaflets, although these structures are somewhat obscure or occasionally absent in some specimens of G. malayana and G. pseudoevodiaefolia . The domatia vary in size from ca. 0.2 to 3 mm in diameter, depending on the species, but when present they always appear (in dried material) as a small tuft of dense, short trichomes, presumably associated with secretory cells.

Key to the species of Gamblea

1. Central leaflet rhomboid to slightly trullate, 1.2-1.8(-2.5) times as long as wide, with 3-4(-5) secondary veins on each side of midvein, domatia on abaxial surface prominent, (1-) 1.5-3 mm long at base of lower secondary veins, tertiary veins weakly raised on abaxial surface; inflorescence a panicle of 2-8 umbellules borne on a single primary axis, occasionally paired with a second shorter, unbranched axis terminating in a single umbellule ( Japan) .................................................................................................................................. 2. G. innovans

1’. Central leaflet narrowly elliptic to elliptic or ovate (often broadly so), usually over 2 times as long as wide, with 5-14 secondary veins on each side of the midvein, domatia on abaxial surface somewhat obscure (rarely absent), 0.5-1 mm long at base of lower secondary veins, tertiary veins distinctly raised on abaxial surface; inflorescence usually a compound umbel or panicle with 2-10 primary axes, occasionally only a single panicle of umbellule ................................................................................................................................................ 2

2. Fruit 4-5.5(-6) × 4.5-6(-6.5) mm, calyx teeth caducous (occasionally minute and persistent); leaflets broadly elliptic to ovate, (1.8-)2-3 times as long as wide (sometimes narrowly elliptic in material from the eastern Himilayas to northern Viet Nam and eastern China only) ........................................................ 1. G. ciliata

2’. Fruit 6-9 × 7-11 mm, with 4-5 usually persistent, triangular calyx teeth; leaflets narrowly elliptic to slightly ovate, 3-4.5 times as long as wide ................................................................................................................ 3

3. Leaflet margins distinctly serrulate, with small, ciliate-hispid teeth 0.2-0.5 mm long, spaced every 3-5 mm; styles free nearly to the base or united to ca. 1/4 of their length; fruit terete in cross-section or occasionally somewhat compressed laterally (northern Viet Nam and Laos, and adjacent Yunnan and Guangxi Prov. in China) .................................................................................................................. 4. G. pseudoevodiaefolia

3’. Leaflet margins subentire, with well developed, dense, divaricate, ciliate-hispid teeth (1-) 1.5-2.5 mm long, spaced every 1-2 mm; styles united for 2/3-3/4 of their length; fruit ± evidently compressed laterally (Peninsular Malaysia, N Sumatra) ........................................................................................ 3. G. malayana