Argyreia roxburghii (Sweet) Choisy var. ampla (Choisy) C.B. Clarke

P. R., Lawand & Shimpale, V. B., 2024, Revision of the genus Argyreia (Convolvulaceae) from India, Rheedea 34 (5), pp. 337-396 : 379-380

Argyreia roxburghii (Sweet) Choisy var. ampla (Choisy) C.B. Clarke in Hook.f., Fl. Brit India 4: 185. 1883. Fig. 11a–d

A twinning or climbing shrub; older stems semiwoody, possess warty lenticels, pale to brown in color, glabrous, young stem herbaceous towards apex, green, hairy, terete. Leaf lamina widely ovate to orbicular, 10–20 × 7–17 cm, apex acute to narrowly acuminate, base cordate, lobes round, overlapping, secondary veins 8–9 on each half on the leaf, upper surface glabrous, lower surface pale green, white strigose; petiole 4–10 cm long, green, terete, white tomentose like stem. Inflorescence axillary lax cymes, 6–7-flowered; peduncles usually longer than the petiole, 7–15 cm long, green, terete, hairy. Flowers bracteate, subsessile. Bracts 2, lanceolate, 1–1.5 cm long, deciduous, green, hairy abaxially, glabrous adaxially. Sepals 5, unequal, outer three long, enclosing flower bud, 1–1.5 cm long, inner two 1–1.2 cm long, tomentose outside, glabrous and concave inside, apex acute or sometimes narrowly acuminate. Corolla infundibuliform, 4.5–6 cm long, 4–5 cm wide, pale pink outer, dark pink inner purple, throat dark purple, c. 1 cm in diam., corolla lobes rounded, hairy on midpetaline bands. Stamens 5, unequal, 3 short, 2 long, longer 2–2.5 cm long while shorter 1.5–1.8 cm long; filaments white, glandular hairy and dilated at base; anthers c. 4 mm long, white. Ovary pale green, 5 mm in diam.; style single, c. 2.5 cm long; stigma biglobose, white. Berries 0.8–1.0 cm, yellow, fleshy.

Flowering & Fruiting: Flowering from September to November and Fruiting from late November to January.

Habitat: The species found growing on disturbed forest lands, along the forest borders.

Etymology: The species is named after William Roxburgh.

Distribution: India (Assam, Arunachal Pradesh, Meghalaya, Mizoram and West Bengal), Nepal, Myanmar, Thailand and Singapore.

Specimens examined: INDIA, Assam, Khasi and Jaintia Hills, Umrangso Dam , 23.02.2007, R. S .

Barnah 114006 (ASSAM); Khasi and Jaintia

Hills, Garampani to Raliang, 27.08.1968, N. P .

Balakrishnan 46940/47087/39507 (ASSAM);

Kokrajhar District, Chakrasila WLS, 26.07.2006,

Ranjit Daimary 111659 (ASSAM); Darrang District ,

Aka Hills, Dhansiri & Dikrai Rivers, 1934, N.L. Bor

15252 (ASSAM); Kamrup District , Loharghat to

Rajapara, 21.10.1965, A. S. Rao 42427 (ASSAM) ;

Guwahati, near Basistha temple, 9.11.2017,

P.R. Lawand 059 (NCK). Arunachal Pradesh, Tirap District, Kheti to Thincha , 22.08.1958 , G.

Panigrahi 14609 (ASSAM). Meghalaya, Khasi and Jaintia Hills, Bishop Falls , 30.08.1931, S. K .

Sharma 9320 (ASSAM); West Garo Hills District ,

Tura , 29.08.1962, D. B . Deb 28825 (ASSAM); Khasi and Jaintia Hills , Barapani Forest , 26.11.1930, P . C .

Kanjilal 8744 (ASSAM); West Garo Hills , Nokrek

Biosphere Reserve , Near Oragitok, 23.06.2007, V. K .

Singh & Bikram Singh 115751(ASSAM); West Jaintia

Hills District, Jowai, August 1892, Dr. King’s collector

s.n. (CAL); Shillong, near Barapani, 30.10.2017, P . R .

Lawand 022( NCK). Mizoram, Aizawl , Lushai Hills, 24.09.1953, B . Godfrey 553 ( CAL) . West Bengal, Jalpaiguri District, Phulbari , 04.09.1975, M . K. V .

Rao 61501 (ASSAM); Mahananda WLS, Sevoke

(North range), 22.10.2007, T. K. Paul & Anant Kumar

42464 (CAL); West Dinajpur District, Chopra,

25.08.1984, R. N. Banerjee 186674 ( CAL); Jalpaiguri

District, Chapramari WLS, s.d., J. Bhattacharya s.n.

(CAL).

Vernacular Names: Roxburgh’s morning glory (English).

Notes: The leaves of this species resemble those of A. hookeri , but the latter has sericeous-tomentose leaves, whereas A. roxburghii has glabrous or nearly glabrous leaves. A. roxburghii is further distinguished by its large oblong-lanceolate bracts, larger outer bracts, and larger fruit size. The name Ipomoea multiflora was first published by Roxburgh (1824). However, it became a later homonym of I. multiflora Roemer & Schultes ( Syst . Veg., ed. 15 bis 4: 234. 1819). As later homonyms are illegitimate and subject to rejection, Sweet (1826) provided a replacement name, Ipomoea roxburghii . Subsequently, Choisy (1834) transferred this name to the genus Argyreia , renaming it Argyreia roxburghii (Sweet) Choisy.

Figures

Fig. 11. Argyreia roxburghii (Sweet) Choisy (a-d): a. Flowering twig;b. A flower;c. Corolla front view;d. Sepals.Argyreia sericea Dalzell (e-g): e. Leaf abaxial surface; f. Inflorescence; g. Bracts. Argyreia setosa (Roxb.) Sweet (h-k): h. Inflorescence; i. Corolla top & side view;j. Bracts; k. Infructescence.