Justicia scandens Vahl, Symb. Bot.

P., Soumya, Y. F., Deng, S. S., Dash & Sunojkumar, P., 2023, A taxonomic revision of the genus JUStICIa (Acanthaceae) in Peninsular India, Rheedea 33 (4), pp. 270-331 : 310-311

Justicia scandens Vahl, Symb. Bot. 2: 7. 1791. Rhinacanthus scandens (Vahl) M.R.Almeida, Fl. Maharashtra 4 A: 86. 2003 Type: INDIA, Malabar , s.d., Koenig s.n. (C [ C10005001 digital image!]).

Justicia glabra J.Koenig ex Roxb., Fl. Ind. 1: 132. 1820; T.Anderson, J. Linn. Soc. Bot. 9: 516. 1867; C.B.Clarke in Hook.f., Fl. Brit. India 4: 535. 1885; Gamble,Fl. Madras2:1079.1921;L.H.Cramer, Revis. Handb. Fl. Ceylon 12: 117–118. 1998. Rhaphidospora glabra (J.Koenig ex Roxb.) Nees in Wall ., Pl. Asiat. Rar. 3: 115. 1832. Wight, Icon. Pl. India Orient. 4: 7. t. 1554. 1850. Lectotype (designated by Soumya

& Sunojkumar, 2019a): INDIA, s.d., Koenig s.n. (BM [BM001253079 digital image!]). FigS. 26 & 27

Annual herbs or subshrubs, up to 1.5 m tall; stems erect, cylindrical, dichotomously branched; branches stout, green, striate, pubescent; internodes 2.5–11 cm long. Leaves petiolate; laminae cordate to widely ovate or widely elliptic, 7–10 × 4–6.5 cm, base rounded to cuneate, margins entire or undulate, apex acuminate, chartaceous, glabrous on both surfaces; veins prominent, secondary veins 4–7 pairs, venation simple craspedodromous; petioles 1–7 cm long, densely pubescent. Inflorescence terminal or axillary dichasial cymes, up to 18 cm long; peduncles slender, 3–9 cm long with divaricately dichotomous branches, densely pubescent with glandular hairs. Flowers pedicellate, 0.85–1 × 0.37–0.45 cm; pedicel 0.5–1.5 cm long, glandular; bracts small, ovate to triangular, 1–1.5 × 0.4–0.6 mm, apex acute, scabrous, greenish, densely pubescent; bracteoles two, similar to bracts. Calyx deeply 5-lobed, 3.5–4 × 1–1.25 mm at anthesis, accrescent, 4.5–5 × 1.25–1.5 mm in fruits, greenish; lobes lanceolate to linear, equal, apex acute, scabrous, densely pubescent. Corolla creamy white with purple striations on lower lip, densely hirsute outside, glabrous inside except in the throat; tube cylindrical, 2.7–3.25 × 1.75–2 mm, slightly enlarged in throat; upper lip erect, ovate to triangular, 4–4.5 × 2.5–3 mm, apex obtuse or acute, hooded; lower lip 3-lobed, lobes unequal, middle lobe ovate to triangular, 5–6 × 2.5–3 mm, apex acute; lateral lobes oblong to elliptic, 4–5 × 1.5–2 mm, recurved, apex acute to rounded. Stamens exserted; filaments c. 3 mm long, declinate, white, basally hirsute; anther thecae superposed, equal, elliptic, c. 1 × c. 0.5 mm, purplish with yellowish shade, upper theca dorsally hirsute, lower theca glabrous; appendage white, c. 6 mm long, apex forked. Ovary ellipsoid to oblong, c. 1.3 × 0.6 mm, pale green, glabrous; style filiform, 5–6 mm high, whitish, hirsute in lower half; stigma bifid; nectariferous disc c. 0.5 mm high, pale green. Capsule clavate to oblong with concentric grooves in middle, 12–15 × 3.5–4 mm, apex cuspidate or acute; basal half sterile, narrow, brown, densely pubescent. Seeds 4, reniform to sub-orbicular, 2.75–3 × 3–3.3 mm, pale or dark brown; testa echinate.

Flowering & fruiting: Flowering from September to March; fruiting in April.

Habitat: Grows in moist deciduous forests, near waterfalls, along riverbanks and stream sides, along forest margins at elevations between 275 and 875 m.

Distribution: Tropical and southern Africa, Madagascar, tropical Asia and India.

Specimens examined: INDIA, Andhra Pradesh, Vishakhapatnam district, Marripakala, 26.05.1966, G. V. Subba Rao 27418 (MH); Kurnool district, Ahobilum upper side, 22.11.1969, J.L. Ellis 32588; Gajulapalle, 08.11.1906, C.A. Barber 8067 (MH). Karnataka, Bellary district, Sanduru, 08.1901, s.coll. s.n (MH); Mysore district, St. Philomena college, 10.03.1964, K.M Sebastine 18722 (MH). Kerala, Idukki district, Chinnar riverside, 05.04.2016, P. Soumya, Dilsha & P. Sunojkumar 145388; Ibid., 13.05.2018, P. Soumya & P. Sunojkumar 138516 (CALI). Tamil Nadu, Coimbatore district, Aliyar submergible area, 24.07.1962, K.M. Sebastine 1456; Ibid., 29.11.1962, K.M. Sebastine 15347; Kuridimalai, 04.12.1956, K. Subramanyam 1603; Ibid., 23.02.1957, K. Subramanyam 2438; Marudhamalai, 11.03.1917, s.coll. 14731; Ibid., 13.09.1956, K.M. Sebastine 723; Ibid., 28.09.1956, K.M. Sebastine 882 (MH); Sadivayal, Adivaram Experimental plot, 13.02.1964, K.N. Subramanian 1113 (FRC); Siruvani, 28.08.1960, A.N. Henry 503 (MH); Ibid., 19.01.1982, K.N. Subramanian 7760 (FRC); Valankulam, 31.01.1965, M. Chandrabose 28704; Waterfalls estate, 10.07.1961, J. Joseph 12805 (MH); Dharmapuri district, Buddireddipatti, 20.12.1913, s.coll. 9710; Hogenakkal forest, 19.07.1964, E. Vajravelu 20711; Ibid., 25.11.1964, E. Vajravelu 21936 (MH); Krishnagiri district, Rayakottai, 27.12.1916, s.coll. 13923 (MH); Madurai district, Gavigundumalai, 21.02.1958, K. Subramanyam 5393; s.loc., s.d., Beddome s.n. (MH); Nilgiris district, Kunjapanai slopes, 07.11.1970, E. Vajravelu 36766 (MH); Ramanathapuram district, Ayyanarkovil, 24.02.1979, N.C. Nair 61421 (MH); Theni district, Suranganur waterfalls, 23.06.1959, K. Subramanyam 8173; Vannathiparai, 18.11.1975, K. Vivekananthan 46711 (MH); Villupuram district, Gingee, Pakkamalai R.F., 21.01.1978, K. Ramamurthy 52882 (MH).

Conservation status: The species is primarily found in Tamil Nadu but also occurs in a few places in Andhra Pradesh, Karnataka and Kerala. Considering its occurrence in such a wide area, the species is categorized as Least Concern ( LC) .

Notes: Justicia scandens can be easily distinguished from other species of Peninsular India by its unique dichasial cymose inflorescence with glandular hairs and cordate to ovate leaves with an apiculate apex.

Figures

Fig. 26. Justicia scandens Vahl: a. Habit; b. Inflorescence; c. Flower; d. Flower bud; e. Bract; f. Bracteoles–abaxial side; g. Calyx; h. Corolla– opened;i. Stamens;j. Gynoecium;k. Capsule; l. Seeds (from P. Soumya & P. Sunojkumar 138516;photos by P. Soumya).

Fig. 27. Distribution of Justicia scandens Vahl in Peninsular India. Drawn using R (R Core Team,2023).