Justicia sivadasanii Sunil, K.M.P.Kumar & Naveen Kum., Kew Bull.

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 : 313

Justicia sivadasanii Sunil, K.M.P.Kumar & Naveen Kum., Kew Bull. 70: 55. 2015. Type: INDIA, Kerala, Ernakulam district, Thundathil forest range, Bhuthathankettu , N 10°08.553’, E 076°39.437’, 50 m alt., 13.12.2013, C.N. Sunil & V.V. Naveen Kumar 6183 (MH [ MH00003324 !]) FigS. 28 & 29

Perennial herbs or subshrubs, up to 130 cm tall. Stems erect, terete, striate, divaricately branched; branches slender, dark green, puberulous; internodes 3–8 cm long. Leaves petiolate; laminae elliptic to lanceolate, 4–12 × 1.5–3.5 cm, base attenuate or cuneate, margins sub-entire, apex acuminate or acute, sub-coriaceous, glabrous on both surfaces; veins prominent abaxially, secondary veins 3–11 pairs, venation simple craspedodromous; petioles 0.5–2 cm long, bifariousely pubescent. Inflorescence terminal or axillary spike, up to 20 cm long; peduncles 0.6–2 cm long, bifariousely pubescent. Flowers sessile, one per inflorescence node, secund, 0.8–1 × 0.35–0.4 cm; bracts in opposite pairs, with one sterile and one fertile; sterile bracts triangular to lanceolate, 2.5–3 × c. 1 mm, margins hyaline, ciliate, apex acuminate; fertile bracts lanceolate, 3.5–4 × 1–1.3 mm, margins hyaline, ciliate; bracteoles similar to bracts, but narrower, 3.5– 4 × 1 mm. Calyx deeply 4-lobed, accrescent, greenish; lobes subulate to lanceolate, equal, 5–6 × 0.8–1 mm at anthesis, margins scarious, ciliate, apex acuminate, glabrous. Corolla creamy white with purple striations on lips, hirsute outside, glabrous inside; tube creamy white, cylindrical, 2.2–3.5 mm long, slightly enlarged in throat; upper lip erect, 4–5 × 2–2.2 mm, ovate– triangular, margins entire, apex acute or obtuse, lower lip 3-lobed, obovate to elliptic, 4.5–5.5 × 3.5–4 mm; lobes oblong, equal, apex rounded. Stamens exserted; filaments 2–2.5 mm long, white, glabrous; anther thecae superposed, equal, elliptic, 1–1.2 × 0.3–0.5 mm, purple with yellowish margins, upper theca dorsally hirsute, lower theca glabrous; appendage c. 0.4 mm long, apex acute, white. Ovary ellipsoid, 1–1.4 × 0.3–0.5 mm, pale green, glabrous; style slender, c. 5 mm high, whitish, hirsute in lower half; stigma bifid; nectariferous disc c. 0.5 mm high, pale green, margins undulate. Capsule and seed not seen.

Flowering & fruiting: Flowering from October to March, fruiting not seen.

Habitat: Dense evergreen forest at an elevation of 50 m.

Distribution: Southern Western Ghats.

Specimens examined: INDIA, Kerala, Ernakulam district, Kuttampuzha forest range, Knacherry , 04.01.2014, C. N . Sunil 6181 ( SNMH); Thundathil forest range, Bhuthathankettu, 29.12.2017, P . Soumya & P . Sunojkumar 138599; Ibid. , 17.02.2018, P . Soumya, Nikhil , K. & P . Sunojkumar s.n. ( CALI); Ibid., 14.10.2018, P . Soumya & P . Sunojkumar 157529; s.loc., s.d., s.coll. 08406 ( CMPR) .

Conservation status: The species is currently known from only two nearby localities in the Ernakulam district of Kerala. In the Bhuthathankettu area, we found about 15 mature individuals scattered over 30–50 m 2. According to Sunil et al. (2015), the second Knacherry locality contained very few plants in a 10 m 2 area and these have now disappeared due to various anthropogenic activities, especially forest clearance to create jungle paths for tourist access. The AOO calculated is less than 10 km 2. Therefore, the species is categorized as Critically Endangered (CR) B2ab(ii, iii, iv, v), D.

Notes: Justicia sivadasanii can be distinguished from other species of Justicia in Peninsular India by its narrow inflorescence with uniquely secund spikes.

Justicia tranquebariensis L.f., Suppl. Pl. 85. 1781; Roxb., Fl. Ind. 1: 131. 1820; T.Anderson, J. Linn. Soc. Bot. 9: 513. 1867; C.B.Clarke in Hook.f., Fl. Brit. India 4: 530. 1885; Gamble, Fl. Madras 2: 1079. 1921; L.H.Cramer, Revis. Handb. Fl. Ceylon 12: 112–113. 1998; Sasidh., Biodivers. Doc. Kerala Part 6: Fl. Pl. 347. 2004; Remadevi & Binojk. Fl. Kerala. Acanthaceae 107. 2009. Gendarussa tranquebariensis (L.f.) Nees in Wall ., Pl. Asiat. Rar. 3: 105. 1832; Wight, Icon. Pl. India Orient. 2: 4t. 462. 1843. Adhatoda tranquebariensis (L.f.) Nees in DC., Prodr., 11: 399. 1847. Ecbolium tranquebariense (L.f.) Kuntze, Revis. Gen. Pl. 2: 981. 1891. Lectotype (designated here): INDIA, Tranquebar (Tharangambadi), 1778, J.G. Koenig s.n. (S [S09-6573 digital image!]).

Figures

Fig. 28. Justicia sivadasanii Sunil, K.M.P.Kumar & Naveen Kum.: a. Habit; b. Inflorescence; c. Flower; d. Flower bud; e. Fertile Bract; f. Sterile Bract;g. Bracteoles–abaxial side;h. Calyx;i. Corolla–opened;j. Upper lip;k. Lower lip;l. Stamens;m. Gynoecium with nectariferous disc (from P.Soumya & P. Sunojkumar 138599;photos by P. Soumya).

Fig. 29. Distribution of Justicia sivadasanii Sunil, K.M.P.Kumar & Naveen Kum.,in Peninsular India.Drawn using R (R Core Team,2023).