Hedyotis shoolamudianus Sunil, Naveen Kum. & K.M.P. Kumar, 2020

Kumar, Vannaratta Veettil Naveen, Prabhukumar, Konickal Mambetta, Sunil, Chandrasseril Narayanan, Bhavadas, Narayanan, Sreejit, Chittiyath Madhavan & Balachandran, Indira, 2020, Hedyotis shoolamudianus (Rubiaceae), a new species from Western Ghats, India, Phytotaxa 438 (2), pp. 159-162 : 159-161

Hedyotis shoolamudianus Sunil, Naveen Kum. & K.M.P. Kumar , sp. nov. ( Fig. 1 )

Diagnosis: Hedyotis shoolamudianus superficially similar to H. purpurascens Hook f. (1880: 50) , but can be differentiated in having sessile leaves with sub-cordate to rounded base and acute apex with 3–4 pairs of basal veins, large ovate-triangular stipules with 13–24 elongated eglandular marginal bristles which are appressed to stem on drying, long and pink bracteoles, corolla lobes having equal length of corolla tube, long staminal filaments in inserted and exserted flowers and long style in exserted flowers.

Type:— INDIA. Kerala, Ernakulam district, Variyam forest, Shoolamudi , alt. 1251 m, 26 September 2015, C.N. Sunil, Naveen Kumar & K. M. Prabhukumar 7234 (Holo: CMPR ; Iso: MH , CALI )

Erect sparsely branched under-shrubs or shrubs, 70–150 cm high; branches leafy above with scars of stipules and fallen leaves below, deep purplish or bluish-green, acutely 4- angled above; internodes distinctly longitudinally grooved below the stipule, glabrous. Leaves sessile, 2.5–7.5 × 0.6–1.7 cm, narrowly ovate-lanceolate to oblong-lanceolate, sub-cordate to rounded at base, revolute at margins, acute at apex, sub-coriaceous, yellowish-green when dry, glabrous; veins 3–7 pairs, impressed above and raised below, 3–4 pairs palmately veined from base to apex and 1–3 pairs pinnately veined from midrib above; stipules free, persistent, 5–13.5× 2.5–5 mm, ovate-triangular, pectinately elongating with 13–24 marginal teeth, pubescent on abaxially at base, sub-coriaceous, teeth brownish, 0.5–4 mm long, flat, acute, not glandular. Inflorescence terminal panicle of corymbose cymes, 4–14 × 4–13 cm; branches slender, dichotomous, angular, grooved, pinkish, glabrous. Flowers sessile, pinkish, distylous; bracts foliaceous, 0.4–1.6 × 0.1–0.3 cm, linear-lanceolate, acute at apex, 1-veined, glabrous; bracteoles 2–3 × 0.7–1 mm, lanceolate, obtuse at apex, not fimbriate, 1-veined, glabrous, pinkish. Hypanthium ca. 2.5 × 2 mm, ovoid, angular, pink. Calyx pink; limb 0.7–1 mm long; lobes 4, erect, 4–5.5× 1–1.2 mm, oblong, microscopically serrate at margins, obtuse at apex, coriaceous, 1- veined, pinkish with dark purple tip. Corolla pink; tube 5–6 mm long, sparsely pubescent inside; lobes 4, 5–6× 1.3–1.6 mm, narrowly oblong, sub-acute and beaked at apex, minutely pubescent inside. Thrum flowers: Stamens exerted; filaments 2.8–3 mm long, pale purple; anthers 1.6–2 mm long, linear, dark blue, medifixed. Style inserted, 3–4.5 mm long, pale purple. Pin flowers: Stamens inserted; filaments 0.2–0.3 mm long; anthers 1.6–2 mm long, linear, dark blue, medifixed. Style exerted, 8–10 mm long, pale purple, slightly curved. Stigma 2-fid, 1–1.2 mm long, ovate obtuse, papillose. Capsules sessile, crowned with erect, persistent calyx lobes, 3.5–4.5 × 2.3–3.2 mm, ellipsoid, glabrous, reticulate, pinkish, septicidal. Seeds 10–18, 1–1.2 × 0.6–0.8 mm, angular, black, reticulate.

Flowering & Fruiting:— September–February.

Etymology:— The specific epithet is named after the type locality, Shoolamudihills, which is the highest peak in Ernakulam district, Kerala.

Habitat & Distribution:— The new species is grown in the high altitude grasslands in association with Kleinia subrahmanianii Sunil & Naveen Kumar (2017: 119) .

Notes:— Hedyotis shoolamudianus , although look similar to H. purpurascens & H. swertioides Hook. f. (1880: 51) , it can be easily distinguished from the field itself by its purplish branches and sessile leaves with palmate veins from the base. A detailed comparison of all the 3 species are given in Table 1 .

Figures

FIGURE 1. Hedyotis shoolamudianus Sunil, Naveen Kum.& K.M.P. Kumar, sp. nov. A. & B. Habits; C. Base of leaves showing sessile nature and round shape with stipules; D. Leaves dorsal and ventral surface; E. Stipules; F. Single pin flower; G. Calyx with gynoecium of thrum flowers; H. & I. Bracts (showing large and small in length); J. Capsule. (Photos: KM Prabhu and VV Naveen Kumar)