1. Damnacanthus angustifolius Hayata, J. Coll. Sci. Imp. Univ. Tokyo. 25(19): 113. 1908.
台湾虎刺 tai wan hu ci
Damnacanthus angustifolius var. altimontanus J. C. Liao; D. angustifolius f. stenophyllus (Koidzumi) T. Yamazaki; D. angustifolius var. stenophyllus (Koidzumi) Masamune; D. stenophyllus (Koidzumi) Masamune; Tetraplasia angustifolia (Hayata) Koidzumi; T. stenophylla Koidzumi.
Dwarf to low shrubs, 0.5-1 m tall. Branches glabrous, without spines, when young subquadrate or usually with 8 alternately thick and thin longitudinal ridge lines, becoming 4-angled and yellow. Petiole of developed leaves 1.5-5 mm, glabrous; leaf blade drying stiffly papery, narrowly lanceolate, narrowly elliptic, linear-lanceolate, elliptic, or lanceolate-elliptic, 5-14 × 0.5-3 cm, glabrous throughout or sometimes sparsely puberulent to hispidulous adaxially, base acute to cuneate, margins flat and entire or irregularly serrulate, apex acute to acuminate; midrib thinly prominulous adaxially; secondary veins 5-9 pairs; stipules caducous, interpetiolar, triangular to spatulate, 0.5-1 mm, glabrous, acute to glandular-fimbriate. Inflorescences glabrous. Pedicels 2-5 mm. Calyx glabrous; hypanthium portion turbinate, 1.2-1.5 mm; limb ca. 1 mm, lobed for ca. 1/2; lobes triangular. Corolla white, glabrous outside; tube 6-8 mm; lobes triangular, 2-2.5 mm. Drupes oblate, ca. 4 × 6 mm. Fl. Jan-Apr, Oct, fr. Jan, Jun, Oct-Nov.
● Primary forests; 1000-2500 m. Taiwan.
Damnacanthus angustifolius var. altimontanus is recognized as distinct in the Kew Rubiaceae checklist (Govaerts et al., World Checkl. Rubiaceae; http://www.kew.org/wcsp/rubiaceae/; accessed on 15 Sep 2010) but was formally synonymized in the Fl. Taiwan (ed. 2, 4: 251. 1998), which is followed here.
This species was reported to be distylous by Naiki and Nagamasu (Amer. J. Bot. 91: 664-671. 2004). This species was reported from Guangdong by Merrill and Chun (Sunyatsenia 1(1): 80. 1930) but said to be restricted to Taiwan by Y. Z. Ruan in FRPS (71(2): 173-174. 1999); the Guangdong plants were apparently included by Ruan (loc. cit.: 174-175), followed here, as Damnacanthus labordei.