Cornus subg. Syncarpea in Flora of China @ efloras.org

5. Cornus subg. Syncarpea (Nakai) Q. Y. Xiang, Acta Phytotax. Sin. 25: 128. 1987.

四照花亚属 si zhao hua ya shu

Benthamia subg. Syncarpea Nakai, Bot. Mag. (Tokyo) 23: 41. 1909.

Shrubs or small trees, evergreen or deciduous. Flower buds terminal, globose to ovoid, exposed or with scales; leaf buds axillary or terminal, with scales or exposed. Leaves opposite, petiolate; leaf blade ovate, elliptic, or oblong-lanceolate, leathery or subleathery to papery. Inflorescences cymes, terminal; bracts 4, white or light yellowish. Calyx tubular, slightly to conspicuously 4-lobed. Petals white or yellowish. Filaments slender; anthers yellow, brown, or bluish black, ellipsoid, rarely ovoid-ellipsoid. Ovary 2-loculed; style cylindrical, often ridged and pubescent; stigma truncate to capitate. Fruit of adjacent flowers fused into a compound, multiple stoned berry, reddish orange or red, globose or subglobose; stones asymmetric, seed 1.

Five species: from the Himalayas to E Asia; five species (two endemic) in China.

Species delimitation within this subgenus is controversial. Over 15 new taxa have been published since the 1950s. This treatment follows Xiang (Bull. Bot. Res., Harbin 7(2): 33–52. 1987), who recognized 13 subspecies among four species, i.e., Cornus capitata, C. hongkongensis, C. kousa, and C. multinervosa. However, a preliminary allozyme investigation by Dudley and Santamour (Phytologia 77: 425–430. 1995) suggested that C. capitata subsp. capitata is quite divergent from C. capitata subsp. angustata. Thus, in the present treatment, we recognize C. elliptica as a species separate from C. capitata. Further studies are needed to test the various species delimitations in the group.

The wood of members of this subgenus is hard and is used for making tools. The edible, sweet fruit is sold in village markets and is used for making wine. The trees are excellent garden ornamentals because of their showy bracts.

1 Deciduous tree; leaves papery; inflorescence buds completely covered by two pairs of decussate, pubescent scales; buds mixed. (2)

+ Evergreen tree; leaves subleathery, leathery, or thickly leathery; inflorescence buds exposed in winter. (3)

2 (1) Leaf veins 3 or 4(or 5), curved inward, extending upward, lower ones not reaching apex; base of peduncle often conspicuously ringlike thickened; anthers light yellow or dark blue; stone of fruit light yellow, without red spots. 23 Cornus kousa subsp. chinensis

+ Leaf veins 5 or 6(or 7), curved inward, extending nearly to apex; base of peduncle not conspicuously thickened; anthers dark blue; stone of fruit with scattered red spots. 24 Cornus multinervosa

3 (1) Leaves abaxially yellowish or pale green, glabrous or ± pubescent with brown trichomes, smooth to touch; trichomes fine, appressed, deciduous, leaving brown dots on leaf surface after falling. 22 Cornus hongkongensis

+ Mature leaves abaxially grayish, typically pubescent with short, light gray or white trichomes, rough to touch, rarely smooth or tomentose; trichomes appressed, persistent, rarely deciduous. (4)

4 (3) Peduncles thick, 2–3(–5) cm; infructescences compressed globose. 21 Cornus capitata

+ Peduncles slender, 5–8(–10) cm; infructescences globose. 20 Cornus elliptica

Lower Taxa