Argyreia osyrensis (Roth ex Roem. & Schult.) Choisy

P. R., Lawand & Shimpale, V. B., 2024, Revision of the genus Argyreia (Convolvulaceae) from India, Rheedea 34 (5), pp. 337-396 : 377-378

25. Argyreia osyrensis (Roth ex Roem. & Schult.) Choisy in DC., Prodr. 9: 334. 1845. Ipomoea osyrensis Roth ex Roem. & Schult., Syst. Veg. , ed. 15 [bis] 4: 239. 1819. Lettsomia aggregata Roxb. var. osyrensis (Roth ex Roem. & Schult.) C.B.Clarke in Hook.f., Fl. Brit. India 4: 192. 1883. nom. illeg. Argyreia aggregata Roxb. var. osyrensis (Roth ex Roem. & Schult.) Gagnep. & Courchet, Fl. Gen. Indo-Chine 4: 280. 1915. nom. superfl. Argyreia imbricata (Roth) Santapau & V.Patel var. osyrensis (Roth ex Roem. & Schult.) Santapau & Patel, Trans. Bose. Res. Inst. Calcutta 22: 40. 1958. Lectotype (designated by Staples & Traiperm, 2017): INDIA, “in Osyre, India orientalis”, B. Heyne s.n. Wallich Cat. 1362.2 (K-W digital image!).

Ipomoea imbricata Roth ex Roem. & Schult., Syst. Veg. 4: 249. 1819; “ Ipomoea imbricata ” Roth , Nov. Pl. Sp.: 112.1821. Convolvulus imbricatus (Roth ex Roem. & Schult.) Spreng., Syst. Veg. 1: 613. 1824. Argyreia imbricata (Roth ex Roem. & Schult.) Santapau & V. Patel, Trans. Bose Res. Inst. 22: 40. 1958. Type: INDIA, “India orientali”, B. Heyne s.n. (K).

Lettsomia aggregata Roxb., Fl. Ind. 2: 76. 1824. Argyreia aggregata (Roxb.) Choisy, Mém. Soc. Phys. Genève 6: 427. 1834, nom. illeg. Argyreia osyrensis (Roth) Choisy var. aggregata (Roxb.) K.K.N.Nair in K.K.N.Nair & M.P.Nayar, Fl. Courtallum 2: 241. 1987. Lectotype (designated by Staples & Traiperm, 2017: 462): INDIA, Cultivated in Calcutta Botanical Garden, “ Lettsomia aggregata Roxb. ”, Roxburgh Icone 1792.

Lettsomia mysorensis C.B.Clarke in Hook. f., Fl. Brit. India 4: 192. 1883. Syntype: INDIA. Karnataka, Mysore , s.d. “ Argyreia n.29”, G. Thomson s.n. ( K000830691 digital image!).

Argyreia aggregata (Roxb.) Choisy var. canescens Wight & Arn. , Wight’s Cat. (4) p. 133, 1837. Syntypes: INDIA, Tamil Nadu, Nagapattinam District [Negapatam] Wight 2260 (E [ E00179001 , E00179003 , E00174999 digital images!)] Fig. 10f–i

A climber; stem semi-woody, twisted around the support, white tomentose. Leaf lamina widely elliptic to orbicular, 9.5–15 × 9–15 cm, exudes milky latex if cut, apex emarginate, base cordate, glabrous above, white tomentose beneath, secondary veins 8–9 pairs, raised conspicuously beneath; petiole white tomentose, 5–16.5 cm, terete, not grooved dorsally. Inflorescence axillary, sub-capitate cyme, 12–15-flowered, inflorescence gathered at apical branches in raceme fashion; peduncles 6– 2 cm long, longer than the petiole, white tomentose. Bract 1, orbicular, 0.9–1.0 × 0.9–1.1 cm, white tomentose above, glabrous inside, leaves scar when fall. Flower bracteate, pedicellate; pedicels 0.5–0.7 cm long. Sepals 5, enclosing almost entire corolla tube, unequal outer two larger, 1.0–1.3 × 0.5–0.7 cm, obovate, apex round, inner three smaller, 0.8–1.0 × 0.2–0.3 cm, oblong, apex round, white cottony tomentose outside, glabrous inside. Corolla campanulate, 1.2–1.7 cm long and c. 1 cm across, corolla lobes deflexed, hairy on midpetaline bands. Stamens 5, exserted from the corolla mouth, equal, c. 1.5 cm long; filaments pink; anthers 2–4 mm, pink. Ovary 3–4 mm tall; style 1, c. 1.5 cm long, white; stigma biglobose, white, papillate. Berries red, c. 1 cm across.

Flowering & Fruiting: Flowering from August to October and fruiting from late Octoberto December.

Habitat: Grows in open forests.

Etymology: The species is named after the type locality, ‘Osyre (currently Odisha or Orissa) in India.

Distribution: India (Andaman & Nicobar Islands, Karnataka, Kerala, Orissa and Tamil Nadu), Bangladesh, China, Myanmar, Sri Lanka and Thailand.

Specimens examined: INDIA, Andaman & Nicobar Islands, Andaman, s.d., s. coll . 5851

(CAL). Karnataka, Uttar Kannada District, North Kanara , Feb. 1886, W . A . Talbot 1560 ( BSI) ;

Belgaum District , Vantamuri-Pachchhapur road, 15.10.2011, Mandar Datar 25374 ( AHMA) ;

Uttar Kannada District, Dharwad, 20.03.1956,

Z.F. Kapadia 1779 (BLAT); Uttar Kannda

District, Dharwad, 01.04.1956, N. A. Irani 1826

(BLAT); Shimoga District, Shimoga, October

1908, A. Meebold 10101 (CAL); North Canara

District , North Canara, February 1886, W. A .

Talbot 1560 ( CAL); Belgaum District , Muchundi village, 14.01.2017, P . R . Lawand 020 (NCK).

Kerala, Tirunelveli District, Reserve Forest to old Courtallum , 01.03.1976, K. K. N. Nair 5218

(CALI); Kozhikode District, Calicut University

Campus, 06.10.1974, V. V . Sivarajan 1528 (CALI);

Tirunelveli District, Courtallum, Vayuthamalai,

04.12.1974, K. V. Sankaran 5529 ( CALI); Quilon

District, Kottavasal, 27.07.1994, A. Nazarudeen

21785 ( TBGT). Tamil Nadu, Madurai District, Sirumalai , 15.09.1957, s. coll . 2848 ( BSI); South

Arkot District , Vajnikughi, 22.10.1983, K .

Ramamurthy 79651 (CAL); Madurai District,

Karandamalai, 29.10.1977, M. Chandrabose 51719

(CAL); Kanyakumari, Kalasekaran, 20.07.2012,

T. Shaju 74013 (TBGT); Madurai, Karandamalai,

29.10.1977, M . Chandrabose 57719 (MH).

Notes: The species is closely related to A. bella but differs by orbicular leaf shape and smaller leaves, ovate-obovate bracts and obovate outer, oblong inner sepals.

Figures

Fig. 10. Argyreia nervosa (Burm.f.) Bojer (a-e):a. Habit;b. Leaf abaxial surface;c. Flower with bracts;d. Bracts;e. Infructescence. Argyreia osyrensis (Roth ex Roem. & Schult.) Choisy (f-i): f. Flowering twig; g. A flower; h. Sepals; i. Infructescence. Argyreia pilosa Wight & Arn. (j-n): j. Habit;k. Inflorescence; l. Bracts;m. Sepals; n. Infructescence.