Argyreia sikkimensis (C.B. Clarke) Ooststr., Blumea

P. R., Lawand & Shimpale, V. B., 2024, Revision of the genus Argyreia (Convolvulaceae) from India, Rheedea 34 (5), pp. 337-396 : 386-387

31. Argyreia sikkimensis (C.B. Clarke) Ooststr., Blumea 7: 178. 1952. Lettsomia sikkimensis C.B.

Clarke in Hook.f., Fl. Brit. India 4: 194. 1883.

Lectotype (designated by Mill, 1999): INDIA, West

Bengal, Darjeeling, Pomong, 3000 ft., 23.08.1869, C. B . Clarke 8808 ( K [ K000830672 digital image!]; Isolecto K [ K000830674 , K000830677 ,

K000830673, K000830675, K000830676 &

K000830678 digital images!], C [C10009596

digital image!], M [M-0184922 digital image!],

P [P00584832, P00584833 & P00584834 digital images!]).

Argyreia venusta Choisy, Mém. Soc. Phys. Genève

6: 419. 1834. Argyreia argentea (Roxb.) Sweet var. venusta (Choisy) C.B.Clarke in Hook.f., Fl.

Brit. India 4: 185. 1883. Type: INDIA, Assam, Goalpara , 06.08.1808, Wallich Cat. 1414/2 s.n. ( GDC [ G00134958 digital image!]). Fig. 13

A climber; stem woody towards the base, younger stem herbaceous towards the apex, appressed strigose. Leaf lamina elliptic, 8–14 × 3–6 cm, apex acute or narrowly acute, base cuneate to obtuse or round, sparsely strigose below, nearly glabrous above,secondary veins 6–8pairs,raised prominently below; petiole 3–7 cm long, appressed strigose like stem, terete, green. Inflorescence axillary lax cyme, 4–6-flowered; peduncles 7–16 cm long, longer than the petiole, strigose, green, terete. Bracts 2–3, oblong to linear, 1–2 cm long, caducous, strigose outer. Sepals 5, elliptic to widely elliptic, persistent and elongate in fruits, 5–8 mm long, subequal, apex obtuse to round, strigose outer, glabrous inside. Corollainfundibuliform, 5–6 cm long; corolla tube 3–3.5 cm long, rose pink in colour, throat dark purple, sparsely hairy on midpetaline bands. Stamens 5, included within corolla tube, unequal, 2 long, c. 3 cm long, 3 short- 2–2.5 cm long; filaments white, dilated and glandular hairy at base; anthers pink 3–4 mm long. Ovary glabrous, 2-celled; style filiform, white; stigma biglobose, papillate, purple in color. Berries c. 8 mm across, 2–4-seeded.

Flowering & Fruiting: August to February.

Habitat: Grows in evergreen forests at higher altitudes.

Distribution: India (Assam, Meghalaya, Sikkim and West Bengal), Bangladesh, and Nepal.

Etymology: The specific epithet ‘sikkimensis’ refers to Sikkim.

Note: The species is closely allied to Argyreia elliptica in its elliptic leaves, small, caducous bracts, few flowered inflorescences with longer peduncle, sepal shape and fruit size.

Figures

Fig. 13. Type of Argyreia SikkimenSiS (C.B. Clarke) Ooststr. [© The Board of Trustees of the Royal Botanic Gardens, Kew. Reproduced with the consent of the Royal Botanic Gardens, Kew].