Euphorbia telanganensis Sadas., K. Prasad & Ramakrishna, 2022

Sadasivaiah, B., Ramakrishna, A., Prasad, K., Devi, N. Sarojini & Rao, Nirmala Babu, 2022, Euphorbia telanganensis (Euphorbiaceae), a new species from Eastern Ghats of Telangana, India, Phytotaxa 572 (3), pp. 283-288 : 284-287

Euphorbia telanganensis Sadas., K. Prasad & Ramakrishna sp. nov. ( Figs 1 & 2 )

Type:— INDIA. Telangana : Nagarkurnool district , Amrabad Tiger Reserve , Way to Dharavagu, Kollam penta beat, 600 m, 14 August 2020, A. Ramakrishna & B. Sadasivaiah 2217 (holotype: CAL; isotypes: HY, TBGH, BSID) .

Diagnosis:— Euphorbia telanganensis is morphologically similar to E. jodhpurensis , but differs in having obovate or elliptic-obovate or ovate-elliptic, and abaxially pubescent leaves (vs. oblong to obliquely oblong or oblong to linearoblong, glabrous), 1.5–2.2 mm long peduncle (vs. c. 1 mm long), turbinate involucre (vs. campanulate), ellipsoid glands (vs. rounded), ellipsoid and unequal limb of glands (vs. orbicular and equal), posterior two limbs are shallowly undulate (vs. margins entire), deeply keeled and trigonous capsules (vs. shallowly keeled and subglobose).

Description:— Erect annual herb, 30–40 cm tall; latex milky. Stem sympodial, dichotomously branched; branches terete, distally filiform, glabrous, pale green; internodes 2–4 cm long, thickened at nodes; stipules triangular, laciniate, less than 1 mm long. Leaves simple, opposite, unequal; leaves on main stem distinctly or slightly larger than the leaves on branches; petiole 1–2 mm long; lamina 1.2–2.8 × 0.7–1.2 cm, obovate or elliptic-obovate or ovate-elliptic, obtuse or rounded at apex, margins serrulate, base oblique, midrib prominent, veins slightly distinct on adaxial surface, glabrous on adaxial surface, pubescent and silver-green on abaxial surface. Cyathia terminal and axillary, solitary, 3–3.5 mm long; peduncle 1.5–2.2 mm long; involucre 1–1.3 × 0.8–1 mm, turbinate, glabrous, greenish; involucral lobes 5, laciniate; glands 4, ellipsoid, yellowish-green; limb of glands 4, distinctly larger than glands, unequal (2 anterior are small; 2 posterior are large), pinkish-white or white; anterior appendages subentire, 0.5 × 0.5 mm; posterior appendages shallowly undulate, 1.1–1.2 × 1.3–1.4 mm. Staminate florets 12–18, exserted, 0.8–1.2 mm long, bracteate; bract simple, 1.2–1.4 mm long; bracteole laciniate; anther lobes subglobose, dehiscing transversely, yellow. Pistillate flowers 3.1–3.4 × 1–1.2 mm, glabrous, pedicel 1.5–1.8 mm long; ovary tricarpellate; styles 3, free from base, each connate up to middle then bifid, 0.6–0.8 mm long, pale pink; stigmas pale pink. Fruiting pedicels recurved; capsules 2– 2.5 × 3.3–3.5 mm, trigonous, schizocarpic, distinctly keeled, glabrous; cocci obscurely venulose. Seeds 3 per capsule, ecarunculate, 1.8–2 × 1–1.1 mm, oblong-ovoid, tetragonal, transversely and obscurely furrowed, truncate at base, stramineous to brown.

Flowering and fruiting:— August to October.

Habitat:— Euphorbia telanganensis is found growing in blackish-red soils of dry deciduous forest at an elevation range of 500– 750m.The common associates are Crotalaria medicaginea Lamarck(1786:201) , Curcuma pseudomontana Graham (1839: 210) , Cymbopogon coloratus ( Hooker 1896: 206) Stapf (1906: 321) , Eleiotis monophylla Candolle (1825: 348) , Heteropogon contortus ( Linnaeus 1753: 1045) Palisot de Beauvois (1817: 836) , Rhynchosia suaveolens ( Linnaeus 1781: 326) Candolle (1825: 387)

Distribution:— Apparently endemic to Amrabad Tiger Reserve (Type locality), Telangana, India.

Etymology:— The specific epithet refers to the state (Telangana state) of its occurrence.

Additional specimens examined:— INDIA. Telangana : Nagarkurnool district, Amrabad Tiger Reserve, Way to Dharavagu, Kollam penta beat, 600 m, 20 August 2020, A. Ramakrishna & B. Sadasivaiah 2225 (paratype: TBGH!); Rasamolabavi , 730 m, 10 October 2021, K. Prasad & B. Sadasivaiah 2298 (paratype: BSID!, TBGH!) .

Conservation status:— In the present floristic survey we have noticed more than 400 individuals at two localities in the Amrabad Tiger Reserve and further explorations in the adjacent areas are required. Presently, the area is well protected as it falls under the Amrabad Tiger Reserve. Therefore, there is no immediate threat to this species but the habitat is prone to forest fires and grazing. Following the IUCN guidelines version 14 ( IUCN, 2019), Euphorbia telanganensis is assessed as Data Deficient (DD).

Note:— The new species, Euphorbia telanganensis and its closely allied species E. jodhpurensis display common morphological characters like small erect herbs, stem dichotomously branched, stipules interpetiolar and laciniate, leaves on main stem distinctly or slightly larger than the leaves on branches, base oblique, dark green on adaxial and silvery green on abaxial surface, presence of petaloid appendages and ecarunculate seeds. It is differing from E. jodhpurensis in having obovate or elliptic-obovate or ovate-elliptic, and abaxially pubescent leaves, 1.5–2.2 mm long peduncle, turbinate involucre, ellipsoid glands, ellipsoid and unequal limb of glands, posterior two limbs are shallowly undulate, deeply keeled, and trigonous capsules. However, another endemic species of Peninsular India, namely, E. erythroclada Boissier (1862: 25) show most congruence with E. telanganensis but differs in having main stem leaves are distinctly or slightly larger than those on branches (vs. main stem and branches of leaves almost equal), leaves pubescent on abaxial (vs. glabrous), involucre 1–1.3 mm long (vs. more than 1.5 mm long), limb of glands unequal, ellipsoid (vs. equal, oblong), posterior two limbs are shallowly undulate (vs. perfectly wavy), capsules deeply keeled and glabrous (vs. shallowly keeled and sparsely hairy).

However, two more related species [ E. clarkeana Hooker (1887: 253) and E. granulata Forsskål (1775: 94) ] were display common key character as leaves of main stems distinctly larger than those on branches, but these species were found to have their own diagnostic features and are clearly distinct from E. telanganensis . Euphorbia clarkeana has prostrate or decumbent habit, stems sparsely hairy, leaves oblong, glabrous, involucre campanulate, limbs of glands minute and as long as glands, capsules obtusely keeled and E. granulata has prostrate habit and covered with densely hispid-villous hairy, leaves ovate-oblong or subobovate, with entire margins, involucre covered with white pilose, ovary hirsute, capsules obtusely keeled and coarsely villous.

Figures

FIGURE 1. Euphorbia telanganensis Sadas., K. Prasad & Ramakrishna sp. nov. A. Habit. B, C, D. Cyathia in different stages.

FIGURE 2. Euphorbia telanganensis Sadas., K. Prasad & Ramakrishna sp. nov. A. Flowering twig. B. Abaxial surface of leaves. C. Stipule. D, E. Cyathia. F. Limb of glands. G. Staminate florets. H. Pistillate flower. I. Capsule. J. Seeds.