Spiradiclis purpureocaerulea H. S. Lo

Tong, Yi-Hua, Xia, Nian-He, Wu, Lei & Vu, Tien Chinh, 2020, Critical notes on Spiradiclis purpureocaerulea H. S. Lo (Rubiaceae) from Vietnam, Adansonia (3) 42 (19), pp. 291-296 : 292

Spiradiclis purpureocaerulea H. S. Lo

( Figs 1A-C ; 2 )

Bulletin of Botanical Research, Harbin 6 (4): 39 (1986).

TYPE SPECIMEN. — China. Guangxi: Longzhou County, Shangjin Town , roadside, on lime stone, 15.VIII.1935, S. P. Ko 55507 (holo-, IBSC [ IBSC 0510671 ]!; iso-, IBK [ IBK 00191520 ]!)

SPECIMEN DATA. — Vietnam. Thanh Hoa: Phu Luong Nature Reserve, Thanh Cong District , on limestone hills, 20°29’29”N, 105°8’26”E, alt. 576 m, 23.X. 2017 , N. H. Xia et al. TYH-1281 ( IBSC).

DESCRIPTION

Perennial herbs, 15-30 cm tall; stems ascending, densely pubescent, hairs brown. Leaves subsessile; blade ovate to ovate-elliptic, 3-9 × 1-4 cm, drying papery, adaxially dark green and densely strigose-hispidulous, abaxially pale green and densely pubescent; apex acute to obtuse; base rounded or obtuse, usually decurrent; secondary veins 7-13 on each side of the midrib; stipules subulate-triangular, 1-3 mm long, pubescent on both surfaces, apex caudate-acuminate, 0.5-1.5 mm long. Inflorescence congestedcymose, terminal, 5-13-flowered; peduncle up to 6 mm, densely pubescent; bracts subulate-triangular, 1.5-3.5 mm long, pubescent on both surfaces. Flowers distylous. Calyx with unicellular and white pubescence outside; hypanthium obconic-globose, c. 2 mm long; calyx lobes narrowly triangular, 3.5-4.5 mm long. Corolla purple red, slenderly salverform, puberulent outside; tube 1.9-2.4 cm long; lobes broadly ovate, c. 6 mm long, obtuse; stamens 5; stigma bilobed; ovary 2-celled, ovules numerous in each cell on peltate axile placentas attached to middle of septum. Long-styled flowers: corolla tube inside with pilose ring above stamens; filaments c. 2.6 mm long, adnate to the base of the corolla tube; anthers linear, c. 3 mm long; style 11-14 mm long, glabrous; stigmas positioned at 2/3 of the corolla tube, lobes linear-oblong, c. 2.8 mm long. Short-styled flowers: corolla tube inside with pubescence near the base; filaments 11-14 mm long, adnate to the corolla tube; anthers linear, c. 3.5 mm long, positioned somewhat above the middle of corolla tube to the level of the throat; style 2-3 mm long, glabrous; stigmas included near the base of the corolla tube, lobes lanceolate, c. 2 mm long.Capsules subglobose, 4-4.5 mm in diam., densely pubescent, opening into 4 valves. Seeds many, angular. Flowering August-October,fruiting October-November.

Figures

FIG. 1. — A-C, Spiradiclis purpureocaerulea H. S. Lo: A, habit; B, brevistylous flower, top view; C, flower, lateral view; D-F, S. coccinea H. S. Lo: D, flower, lateral view; E, longistylous flowers, top view; F, habit

FIG. 2. — Holotype of Spiradiclis purpureocaerulea H. S. Lo, S. P. Ko 55507 (IBSC 0510671).