Ephedra pangiensis Rita Singh & P.Sharma, 2015

Sharma, Prabha & Singh, Rita, 2015, A new species of Ephedra (Ephedraceae, Ephedrales) from India, Phytotaxa 218 (2), pp. 189-192 : 189-191

Ephedra pangiensis Rita Singh & P.Sharma , sp. nov. ( Fig. 1 )

Species similar to E. intermedia but distinguished by the anatomy of the stem, grayish bark, non-bluish branches and its stalked male and female strobilus.

Type:— INDIA. Himachal Pradesh: Pangi nala, Kinnaur, 3000 m, 10 October 2003, Singh & Sharma 86 (holotype IPUH!).

Plants dioecious, erect, 1 m tall. Bark grayish black, branchlets dark green, 1–2 mm in diameter with ridges and furrows, internodes 4–5 cm long. Leaves scaly usually two, sometimes three confined to the nodes, opposite decussate, turning brown at maturity, awl shaped, acuminate, 2–3 mm in length, mostly ½ connate, sheath membranous, later fissured. Male strobilus stalked, subglobose to globose, 3–4 mm long, 1.5–2.0 mm wide with six pairs of flowers, bracts binate in six pairs, cuspidate, 1.5–3.0 mm long, 1.0– 2.5 mm wide, perianth almost equaling the subtending bract, urceolate, acuminate, 2.0–2.5 long, 1–2 mm wide, synangiophore with synangia 3–4 mm long, 1.5–2.0 mm wide, synangia 5–6, usually 3 sessile and 2–3 stipitate, pollen grains golden yellow, dimorphic, ellipsoidal or widely ellipsoidal with protrusion visible at the meridional poles. Female strobilus stalked, 7 × 4 mm, three to four pairs of bracts, bracts mucronate, connate, 1.5–4.0 mm long, 1–3 mm wide. Seeds two, ovate to elliptic, black, 4.5–5.5 mm long, 2.0– 2.5 mm wide, two enveloped, micropylar tube twisted, 3–5 mm long, exserted.

Etymology:—The new species is named after the place of occurrence where it was first located, Pangi Nala near Rekong Peo (Distt. Kinnaur) in Himachal Pradesh.

Distribution and Ecology:— India, known from Rekong Peo, Pangi Nala, Purvan Jhula of District Kinnaur in Himachal Pradesh. Open, dry loose gravel soil, as well as rock crevices, road side cuttings in rainshadow areas of Rekong Peo, Pangi Nala and Purvan Jhula (District Kinnaur) above 3000 m elevation in the North West Himalaya. The studied populations grow in association with Artimisia ( Asteraceae ) and Chenopodium ( Amaranthaceae ).

Additional specimens examined:— INDIA. Himachal Pradesh: Rekong Peo, Pangi Nala, Purvan Jhula upto Spello , 3000 m, October 2003 ; 2004, Singh & Sharma 87, 91, 199, 211, 271, 272, 277 (all IPUH!) .

Taxonomic notes:— Pearson (1929) while discussing the taxonomy of Ephedra , pointed out that the general habit of Ephedra is of little value as a systematic character in the genus because in most species it is profoundly influenced by environment. However, Freitag & Maier-Stolte (1994) were of the opinion that ‘except for widely differing growth form, most Ephedra species look much alike’. Ickert-Bond & Wojciechowski (2004) made the valid point that in Ephedra , where the morphology based taxonomy has been so difficult, the use of molecular sequence data would prove to be an essential tool for taxonomic studies for resolving relationships. Despite all the apprehensions about ecophenotypic variations in Ephedra , a number of morphologically useful diagnostic characters have been selected and utilized by previous authors for taxonomic studies. Meyer (1846) used micropyle or tubilus characters and ( Stapf 1889) classified Ephedra species on the basis of the position and number of bracts of female inflorescence, extent of fusion of bracts specially the innermost, bract structure and their colour at maturity. Sahni (1990) emphasized the taxonomy of Ephedra on the number, size and colour of the seeds and Yang (2005) distinguished species on the basis of seed surface characters. Shape of the male cones, number of flowers, number of synangia and their position ( Freitag & Maier-Stolte 1994), pollen size, shape and number of ridges and furrows and their morphology ( Welten 1957, Steeves & Barghoorn 1959, Kedves 1987, El-Ghazaly & Rowley 1997, Ickert-Bond et al. 2003) were all used as diagnostic characters. While Pant & Verma (1974) used epidermal and cuticular morphology of stems and leaves, stem anatomy ( Mikage & Kondo 1996, Joshi & Khan 2005), pith character ( Freitag & Maier-Stolte 1994), and wood anatomy ( Carlquist 1989, 1992, 1996), were also used for taxonomic discrimination of Ephedra species. In the present study the authors have made an endeavor to utilize the maximum possible morpho-anatomical characters to substantiate the status of our new taxon.

Ephedra . pangiensis is similar to E. intermedia in having a strong woody habit, resinous brown pith, red fleshy bracts at the time of maturity of female strobili, twisted micropylar tube and a biovulate strobilus bearing mostly two seeds. It differs in having grayish stem bark, dark green, thin (1–2 mm in diameter) branchlets (vs. bluish green branchlets, 1.5–2.5 mm in diameter) and scale leaves with acute to acuminate apex. In cross-section, internodes of E. pangiensis show large sized palisade parenchyma cells (50.0–62.5 μm long and 15.5–20.0 μm wide), vs. 35–40 μm long and 10.0–12.5 μm wide in E. intermedia . Diameter of resinous pith is narrow, 750–875 μm as compared to 1375–1625 μm in E. intermedia . Male strobili are stalked having six pairs of flowers compared to categorically sessile male strobili with four to five pairs of flowers in E. intermedia .

Pollen grains of E. pangiensis exhibit characteristic prominent protrusion at the meridional poles. Female strobili are also stalked, bearing black, ovate to elliptic seeds (4.0– 5.5 mm long and 2.0– 2.5 mm wide) as compared to the sessile with brownish black and ovate seeds (4–5 mm long and 2.0– 2.5 mm wide) also demarcates E. pangiensis and E. intermedia , respectively.

Figures

FIGURE 1.—Ephedra pangiensis. A. Habit. B. A magnified portion of stem showing scaly leaves at the nodal region. C. Surface view of epidermis showing stomata (st). D. Surface view of epidermis showing external pore (p). E. Surface view of epidermis showing papillations (pp). F. T.S of Stem (Diagrammatic). G. T.S. of Stem, a portion enlarged, cu—cuticle, st—stomata, ep—epidermis, sef— subepidermal fibres, co—cortex, cf—cortical fibres, pf—pericyclic fibres, ph—phloem, x—xylem, pt—pith, rs—resinous substance. H. Male strobilus I. Perianth. J. Synangiophore with synangia. K. Pollen grains. L. Female strobilus M. Seed in lateral and front view with twisted micropyle. Drawn by P. Sharma.