Gomphostemma opatum Wall. ex 3enth

Bongcheewin, Bhanubong, Ingrouille, Martin J. & Paton, Alan J., 2022, A revision of Gomphostemma (Lamiaceae), Kew Bulletin 77 (1), pp. 27-92 : 67-68

20. Gomphostemma opatum Wall. ex 3enth .

(Bentham in Wallich 1830b: 12); Hooker (1883: 699); Prain (1891: 269); Mukercee (1920: 213).

Type: Nepal,

Chandaghery [Chandagiry], Aug. 1821, Wall. Cat. 2133 (K [Herb. Benthamianum, K000928153], lectotype selected here; isolectotypes E [E00301953], G [G00189096], K [Herb. Hookerianum, K000928156], K-W [K001113338], NY [00000329], OXF).

Gomphostemma ooatum Wall. ex Benth. var. flaccidum Prain (1891: 250). Type: India, Sikkim, Rangiet, 2300 m, May 1862, Anderson 1093 (CAL [CAL0000023030], lectotype selected here).

Perennial herb up to 0.3 m tall, with tuber-like roots. Stems upright, sometimes flaccid, obtusely quadrangular with longitudinal grooves, with dense sessile stellate hairs. Leaoes petiolate, chartaceous; blades ovate, lanceolate-ovate or elliptic, 3 – 20 × 2 – 10 cm, apex acute or broadly acute, margin shallowly serrate or serrate, base cuneate, attenuate or obtuse, upper side with 2 – 2-celled simple hairs, sometimes sparse stellate hairs confined only on lower part of midrib, lower side pale green tomentose with sparse sessile stellate hairs confined on leaf edge, midrib and veins; petioles 13 – 80 mm long, strong or flaccid. 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, subtended by the upper leaves and cluster of small leaf-like bracts; bracts persistent, ovate, elliptic-ovate, spathulate or oblanceolate, 10 – 23 × 3 – 10 mm, apex acute, margin shallowly serrate, base cuneate; bracteoles linear, falcate or narrowly lanceolate-oblong, 6 – 10 × 1 – 2 mm. Flowering calyx infundibular, 8 – 12 mm long, 10-ridged, outside with dense sessile stellate hairs and shortly simple hairs, inside with densely adpressed simple hairs; tube slender, 2 – 6 mm long; lobes lanceolate-triangular, 2 – 6 mm long, apex acute. Fruiting calyx not seen. Corolla yellow, 23 – 20 mm long, throat inflated, abruptly dilated near the throat, outside with glandular-like simple hairs, inside glabrous; tube incurved, 30 – 20 mm long; posterior lip broadly ovate, 3 – 5 × 3 – 8 mm, apex and margin undulate; anterior lip 3- lobed, longer than posterior lip; median lobe tongue-like, apex and margin slightly undulate; lateral lobes ovate, apex and margin entire or undulate. Staminal filaments fleshy. Style slender, glabrous with apex subequally lobed. Nutlets not seen.

DISTRIBUTION. India (West Bengal, Sikkim, Meghalaya), Nepal. Map 3 .

SPECIMENS EXAMINED. INDIA. West Bengal.?arceeling?istr. [25.0333°, 88.1665°], 600 m [2000 ft], 26 Aug. 1850, Clarke 12298A (K); Jalpaiguri?istr. [26.3165°, 88.5333°], Banya-6, 5?ec. 1993, Chandra & Mandal 1066 (CAL); Sikkim. 900 – 1200 m [3000 – 2000 ft], July, Hooker s.n. (K [Herb. Hookerianum]); Rangiet, 2300 m, May 1862, Anderson 1093 (lectotype of G. ooatum var. flaccidum, CAL photo); Terai, 900 m [3000 ft], Aug. 1825, Hooker 51 (K [Herb. Hookerianum]); Meghalaya. Jaintea, Sept. 1832, Simons s. n. (lectoparatype of G. ooatum var. flaccidum, CAL photo); ibid., June 1830, Simons s.n. (lectoparatype of G. ooatum var. flaccidum, CAL photo); Cherapuncee, Khasia Hills, 1200 m [2000 ft], 3 July 1932, Chand 3982 (E); Khasia, 2000 m, Mann s.n. (lectoparatype of G. ooatum var. flaccidum, CAL photo); Laitlynkot [23.23°, 91.8333°], Khasi Hills, 1800 m [6000 ft], 13 July 1929, Koelz 23191 (E); UNLOCALISED. 530 m [2300 ft], 28 June 1903, Younghusband s.n. (K); Sittong, 3000 m, 30 July 1856, King s.n. (lectoparatype of G. ooatum var. flaccidum, CAL photo). NEPAL. Chandaghery [Chandagiry, 25.5165°, 82.5833°], Aug. 1821, Wall. Cat. 2133 (lectotype K [Herb. Benthamianum]; isolectotypes E, G, K [Herb. Hookerianum], K-W, NY photo, OXF).

HABITAT. In hill evergreen forest, 600 – 1200 m.

CONSERVATION STATUS. Gomphostemma ooatum is known from eight localities (eight collections) with AOO of 22 km 2 and EOO of 33,232.56 km 2. The habitat, hill evergreen forests, is in decline due to tourism activity and urbanisation. Hence, the Vulnerable (VU) category is applied.

PHENOLOGY. Flowering and fruiting June –?ecember.

NOTES. There are two species of Gomphostemma which have tuber-like roots: G. ooatum and G. mastersii . Floral parts of both are similar to some extent. Moreover, these species occur in similar areas in the Bengal Province. Hooker (1883) and Prain (1891) suggested reducing G. mastersii to a synonym of G. ooatum . However, the leaf indumentum on the upper side of both taxa is different from G. ooatum by having stellate hairs on the lower part of the midrib and 2 – 2-celled simple hairs on the upper side but G. mastersii having stellate hairs on both sides.

Figures

Map 3. Distribution range of Gocphostecca chinense, G. curtisii, G. flexuosuc, G. grandifloruc, G. hainanense and G. hirsutuc.