Oxygraphis kumaonensis I. D. Rai & G. S. Rawat, 2015

Rai, Ishwari Datt & Rawat, Gopal Singh, 2015, Oxygraphis kumaonensis sp. nov. (Ranunculaceae) from Western Himalaya, India, Phytotaxa 230 (1), pp. 92-96 : 95

Oxygraphis kumaonensis I. D. Rai & G. S. Rawat , sp. nov. ( Figs. 1 , 2 )

Type: — INDIA, Uttarakhand, Kumaon, Pithoragarh district, Najurikot, South-West facing broken-rocky slope, 29°57’35.05”N, 80°24’16.40”E, 4050 m, 6 June 2015, I. D. Rai & G. S. Rawat 11463 (holotype WII!, isotype BSD).

Diagnosis: — Oxygraphis kumaonensis differs from its nearest ally O. polypetala in the presence of lobate leaf margins, clawed petals with broad to round apex, calyx and corolla abaxial surfaces with thin purple to brown coating and typical habitat on the rocks.

Etymology: —The epithet recognises the name of the Type region ‘ Kumaon’, a biodiversity rich area in the Western Himalaya.

Description: —Perennial scapose herbs, 3–6 cm tall. Roots fibrous, base covered by remains of old leaves. Leaves all radical, 2–5, glabrous; petiole 1.5–6.5 cm long, light to dark purple, narrowly sheathing at base; leaf blade round to reniform, 0.5–0.8× 0.6–1.1 cm, base cordate, lobes 7 or sometimes less in the young leaves, middle lobe largest and slightly 3 partite at apex, apex rounded to broadly pointed. Scapes 1, 2–6 cm long, glabrous, white to light purple at sprouting, dark purple at maturity. Flowers solitary, yellowish-brown, 1–1.3 cm in diam., ebracteate; sepals 5, green, oblong to ovate-oblong, 0.4–0.8 cm long, glabrous, leathery, persistent, abaxial surface with purple colour spots/ coating; petals 8–14, 4.5–6.5×2.5–4.0 mm, distinctly clawed, apex rounded to broadly flat, yellow to brown with thin layer purplish-brown irregular spots or coating on the abaxial surface, adaxial surface with 4–6 prominent green to purple veins; stamens 15–26, spirally arranged, 1.8–3.2 mm long, smooth; filaments yellow, 1.2–2.5 mm; anthers oblong; 0.5–0.7 mm long, yellow to brown. Carpels on a sub-globose receptacle, yellow, turning green with maturity, compressed, glabrous, with an elongate subulate beak. Aggregate fruit broadly ovoid, ca. 4 mm in diam.; achenes 1.2–2.2 mm long, obliquely obovate or narrowly obliquely ovate, glabrous.

Phenology: —Flowering: May–June; Fruiting: July–August.

Distribution and Ecology: —The species was found growing on the ledges of moist rocks in the alpine zone. As in case of other species of Oxygraphis , this taxon was found in bloom during early summer just after the snowmelt. The individuals appear to form bunches among cushions of mosses in the crevices of rocks and boulders. Leaf blade is minute and unfolded during the initiation/opening of flower bud and inconspicuous at early flowering individuals whereas it expands after flowering. The area remains under snow from November to May. The slope was dominated by Kobresia hookeri Boeckeler (1875: 4) , K. nepalensis (Nees) Kük. (1909: 40) and K. duthiei C.B. Clarke (1894: 697) whereas in the microhabitat of the species only a few mosses were present packed in the rock crevices and soil along the edges of the rocks.

Conservation status: —The species is restricted to a single locality at Najurikot with an ideal habitat of less than 1 hectare. A total of 40 individuals were found in this area in two small populations of 25 and 15 individuals. This area is under high anthropogenic pressures due to the collection of caterpillar fungus ( Ophiocordyceps sinensis (Berk.) G.H. Sung, J.M. Sung, Hywel-Jones & Spatafora ) and frequent fires on the mountain slopes. According to IUCN Red List Criteria and Categories ( IUCN, 2014) the conservation status of the species is CR under the criteria B1, B2a,b(iii) and D.

Affinities with allied species: —The new species resembles with O. polypetala and O. delavayi in the round, orbicular to reniform leaves but differs in the presence of lobed leaf blade, clawed petals with broad to round margin, outer surface of calyx and corolla with thin purple to brown coating and typical habitat on the rocks. Scapes are one to several in Oxygraphis polypetala whereas only single scape is found in O. kumaonensis .

Figures

FIGURE 1. Oxygraphis kumaonensis I. D. Rai and G. S. Rawat sp. nov: (a). Habit; (b). Single individual with flower, leaves and roots; (c). Petals; (d). Stamen with anthers; (e). Achene.

FIGURE 2. Oxygraphis kumaonensis I. D. Rai and G. S. Rawat sp. nov: (a) and (b). Habit; (c). Flower with different floral parts; (d) Flowers showing purple-brown coating on the petal; (e). Mature flower with persistent calyx, carpels and dried stamen & petals; (f). Mature flower and leaves.