Argyreia lawii C.B. Clarke

P. R., Lawand & Shimpale, V. B., 2024, Revision of the genus Argyreia (Convolvulaceae) from India, Rheedea 34 (5), pp. 337-396 : 369-370

20. Argyreia lawii C.B. Clarke in Hook.f., Fl. Brit. India 4: 190. 1883. Lectotype (designated by

Lawand & Shimpale, 2017): INDIA, Karnataka, Bababoodan Hills, s.d., J. Law 28 (K [K000830722

digital image!]); Isolecto K [K000830721 digital image!], GH [GH00135003 digital image!], P

[P00584825 digital image!]. Fig. 7i–l

A semi-woody moderate height climber or sometimes prostrate shrub; older stems semiwoody, young purple, strigose-villous, hairy, terete. Leaf lamina 7–11 × 3–6 cm, base cordate, apex acute, strigose on both the surfaces, secondary veins 6–7 pairs, conspicuous below; petiole 2–4 cm long, dorsally grooved, purple in color, strigose-villous. Inflorescence a compact 4–9-flowered cyme; peduncle 6–12 cm long, longer than the petiole, purple colored, terete, strigose-villous. Flowers sub sessile, bracteate. Bracts 2, linear-lanceolate, 1–2 cm long, apex acute, bract of flower in fork larger, lance-ovate, prominent midvein, persistent, green, purple at margin, white hairy on both the sides. Sepals ovate, subequal, 0.7–1.0 cm long, apex acute, inner three wider than the outer two, strigose outer, glabrous inside, outer sepal purple margined, inner hyaline on margins. Corolla funnel form, 4–5 cm long, 4–5 cm wide, pink-purple, throat purple c. 1 cm wide, hairy outer on midpetaline bands, corolla lobes twisted in bud and shortly apiculate in flower. Stamens 5, inserted in corolla tube, unequal in length, 2.5–3.5 cm long; filaments pink, dilated and glandular hairy at base; anthers pale pink. Ovary few 1–2 mm in diam.; style 1; stigma biglobose, pink. Berries c. 1 cm across, yellow.

Flowering & Fruiting: Flowering from late July to September and fruiting from October to December.

Habitat: The populations of the species are frequent along the roads at altitude of 700– 800 m. If no support to twin it grows prostrate and if gets support plants climbs up to height of 20 ft.

Distribution: India (Karnataka and Maharashtra); Endemic to peninsular India.

Etymology: The species is named after the collector J.S. Law .

Specimens examined: INDIA, Karnataka, Chickmagalur District, Bababoodhan Hills , base of the hills, 19.01.2018, P. R . Lawand 50 ( NCK) . Maharashtra, Kolhapur District, Bhudargad , 700 m, 11.09.2017, P. R . Lawand & Shimpale 11 ( NCK); Kolhapur District, on the way to Patgaon , October 2017, P. R . Lawand 051 ( NCK) .

Conservation status: The species has been collected from two locations, one in Karnataka and another in Maharashtra. At the latter location, specifically at Bhudargad Fort and Patgaon in Kolhapur district, we observed 4–6 mature individuals, with very low fruit setting in the species. The plant is relatively frequent at Bababudhan Hills, Karnataka, but the total area of occurrence is unlikely to exceed 10 km ². Road clearing, widening, and land conversion for coffee plantations are potential threats contributing to habitat destruction and posing risks to the species’ survival. Based on IUCN Red List criteria ( IUCN, 2024), we propose the conservation status of Endangered (EN B1ab and C2a(i)) for this taxon.

Notes: The species is similar to Argyreia elliptica in leaf shape, indumentum, and flower shape but is clearly distinct in its habit, bract size and shape, and inflorescence architecture. Both A. elliptica and A. lawii were found growing sympatrically but occupy distinct ecological niches.

Figures

Fig. 7. Argyreia invOluCarata C.B. Clarke (a-d): a. Flowering twig; b. Leaf abaxial surface; c. Inflorescence; d. Sepals. Argyreia kleiniana (Roem. & Schult.) Raizada (e-h): e. Flowering twig; f. Leaf abaxial surface; g. Bracts; h. Sepals. Argyreia lawii C.B. Clarke (i-l): i. Flowering twig; j. Inflorescence; k. Bracts;l. Sepals.