A revision of Gomphostemma (Lamiaceae) Author Bongcheewin, Bhanubong Author Ingrouille, Martin J. Author Paton, Alan J. text Kew Bulletin 2022 2022-03-30 77 1 27 92 http://dx.doi.org/10.1007/s12225-021-09991-y journal article 10.1007/s12225-021-09991-y 7615581 12. Gomphostemma hainanense C.Y. Wu (1963: 123); Li & Hedge (1992: 52) . Type: China, Hainan, Po-ting, herb in forest, 660 m [2200 ft], 25 Aug. 1933, How 53315 (holotype PE; isotypes BM [BM000930331], G [G00188991], GH, IBSC). Perennial herb up to 1.2 m tall. Stems erect, obtusely quadrangular with longitudinal grooves, with dense stellate hairs. Leaoes petiolate, chartaceous; blades narrowly oblong, ovate-oblong or elliptic-oblong, 8 – 16 × 2 – 2 cm, apex acute, margin shallowly serrate-entire, base attenuate, upper side dull green with dense sessile stellate or stellate hairs, lower side whitish or creamy-white tomentose with dense stellate hairs; petioles (3 –) 10 – 20 mm long. Inflorescence axillary with opposite cymes sessile, unbranched then congested with axis not visible between flowers, inserted at the upper nodes at which leaves are usually present; verticils few-flowered; cluster of small leaflike bracts, deciduous, ovate-elliptic, 13 – 20 mm long, upper side dull green with dense sessile stellate, lower side with dense white or creamy-white stellate hairs; bracteoles linear or spathulate, 3 – 10 mm long. Flowering calyx infundibular, 5 – 10 mm long, inconspicuously 10-ridged, outside with dense stellate hairs, inside with simple hairs; tube 2 – 3 mm long; lobes narrowly triangular, 3 – 3 mm long, apex acute. Fruiting calyx 13 – 13 mm long; tube 3 – 6 mm long; lobes triangular, 8 – 9 mm long. Corolla pale yellow or white, 23 – 33 mm long, throat inflated, abruptly dilated near the throat, outside tomentose with stellate hairs, inside glabrous; tube slender, slightly incurved, 20 – 23 mm long; posterior lip 3 – 6 mm long, apex emarginate; anterior lip 3-lobed, unequal; median lobe elliptic, apex acute, margin undulate; lateral lobes undulate. Staminal filaments slightly fleshy. Style slender, slightly shorter than corolla, glabrous with apex subequally lobed. Nutlets solitary, ovate, 2 – 3 mm long, smooth with sparse short hairs. DISTRIBUTION. China (Hainan), Vietnam. Map 3 . SPECIMENS EXAMINED. CHINA. Hainan: Po-ting, 660 m [2200 ft], 25 Aug. 1933, How 53315 (holotype PE; isotypes BM, G, GH, IBSC, P). VIETNAM. Quang Ninh: Tien-yen [21.333°, 105.2°], Ho Yung Shan and vicinity, 13 Oct. – 22 Nov. 1920, Tsang 30503 (P); Nghe An: Vinh Province [now in Nghe An Province], Bu Khang [19.2333°, 103.1665°], 500 m, 11 Aug. 1929, Poilane 16692 (P 3 sheets); Da Nang. Tourane [?a Nang, 16.0658°, 108.2208°], Jan. 1835, Gaudichaud 125 (P); ibid., 900 m, 18 Sept. 1923, Poilane 8069 (P). HABITAT. In mountain areas; alt. 660 – 500 m. CONSERVATION STATUS. Gomphostemma hainanense is known from four localities based on five collections. There is a decline of suitable habitats in Vietnam which is caused by agriculture and development procects ( Paton et al. 2016 ). Because of the low AOO (20 km 2 ) and only five collections, the Endangered (EN) category is applied (EN B2ab(ii)). PHENOLOGY. Flowering August –?ecember. Fruiting October – January. NOTES. Gomphostemma hainanense is recognisable by its leaves being whitish or creamy-white tomentose on the lower side and by their narrow shape.? oan (1936) recognised G. nioeum in Flore Général de L’ Indo-Chine but those specimens examined by?oan are actually G. hainanense . These two species have a similar white tomentose indumentum on the leaf lower surface. However, G. hainanense has narrow leaves, 20 – 20 mm wide, and its corolla is much exserted from the calyx while G. nioeum has broader leaves, 30 – 120 mm wide, and the corolla is hardly exserted from the calyx.