Peucedanum pradeepianum K.M.P.Kumar, Hareesh & Indu, 2020

Prabhukumar, Konickal Mambetta, Hareesh, Vadakkoot Sankaran, Pradeep, Ram & Balachandran, Indira, 2020, Peucedanum pradeepianum (Apiaceae: Apioideae), a new species from Western Ghats, India, Phytotaxa 446 (1), pp. 43-48 : 46-47

Peucedanum pradeepianum K.M.P.Kumar, Hareesh & Indu sp. nov. ( Fig. 1 & Fig. 2 )

The new species shares similarities with P. anamallayense , but differs in deeply serrate leaflets, broadly ovate bract, ovate-lanceolate bracteoles with acute apex, pinkish stylopodium, 3–4 lateral and 4 commissural vittae.

Type: — INDIA. Kerala: Palakkad district, Dhoni hills, Palamala, ± 1950 m, N10 º 54’ 37.7’’ E 076 º 37’ 41.4’’, 28 September 2013, K. M. Prabhukumar 7590 (holotype, CMPR, isotypes, CAL, CALI, CATH).

A slender, erect, glabrous, 15–25 cm tall, perennial herb with tufted, 2.5–3.5 cm diam. root-stock. Stems 1–1.7 cm diam. at base, solid, angled, green with purple ridges. Leaves 4–9× 0.8–2.2 cm, opposite, decompound; leaflets dimorphic, basal leaflets obovate, deeply serrate; upper leaflets elliptic to elliptic-lanceolate, serrate. Rachis 4–6 mm long, sheathing at base, sheath glabrous; petiole 1.5–2 cm long, angled, glabrous. Flowers in synflorescence of compound umbels. Umbels 3–5 rayed; rays distinctly equal, 1–2.5 cm long. Involucre bracts 1–3, 4–5 × 1.5–2 mm, broadly ovate, pale brown. Flowers small, 7–12 in single umbel, rather inconspicuous, ca. 2.5 mm diam., all perfect, pedicel 2.5–3 mm long. Involucel usually 5, rarely 4, 1.7–2 mm long, ovate-lanceolate, persistent, pale brown. Sepals ca. 0.6 mm long, linear-lanceolate, acute, green, purple at apex. Petals 1–1.2 mm long, obovate, acute, strongly inflexed, white. Stamens 5, spreading; filaments 1–1.5 mm long,white; anthers ca. 0.5 × 0.6 mm, oblong or sub-globular, yellow. Stylopodium ca. 1 × 0.75 mm, broadly conical, pink, persistent. Style ca. 0.5 mm long, thin, deflexed, transparent. Fruit dorsally compressed, flattened, stramineous with pale pink shades, orbicular. Mericarp 4–6 × 3.5–4.5 mm, ellipsoid, ridge ca. 1 mm wide, 5-ribbed; vittae prominent, 1 dorsal, 4 commissural and 3–4 lateral.

Phenology:— September–January.

Etymology:— The species is named in honour of Dr. A.K. Pradeep, Assistant Professor, Department of Botany, University of Calicut, for his outstanding contributions to the field of Plant Taxonomy.

Distribution, Habitat & Biotic associations:— Peucedanum pradeepianum apparently endemic to the Kerala, India, it grows in grass lands of high wavy mountains of Palamala hills of Dhoni forest, Palakkad, Kerala at about ± 1950 m asl. This area consists of undulating hills, valleys, well clothed with vegetation except for the large grassy area to the south east and the mass of high hills to the south ( Prabhukumar et al., 2014). The new taxon was found growing on the grasslands along with Chlorophytum palghatense K.M.P. Kumar & Avinash (in KMP Kumar et al. 2014: 282), Impatiens concinna Hook. f. (1874: 449) and Leucas dhonimalayensis Sunojk. & K.P. Vimal (2018: 289)

Conservation status:— Peucedanum pradeepianum was collected only from the type locality of Palamala hills, a total 50—100 mature plants have been observed in the type locality. The Extent of Occurrence (EOO) which is about 5 km 2 and Area of Occupancy (AOO) 1 km 2. According to EOO and AOO results and the IUCN (2017) criteria (Area of Occupancy estimated to be less than 10 km 2 and known to exist not more than 3 locations), this species should be classified as Critically Endangered (B1B2biiciii).

Note: — Sivadasania josephiana Mohanan et Pimenov (2007: 900) , a species of monotypic genus also shares the similarities with the genus Peucedanum ,but differs mainly on the laterally compressed fruits, equal keeled lobes and entire marginal ribs. In personal correspondence with Dr. Mohanan, one of the authors of the genus Sivadasania and he commented that “The fruits are dorsally compressed and it is a character of Peucedanum , in Sivadasania the fruits are laterally compressed. From the critical observation on the specimen it is clear that, it should be a new species under Peucedanum ”. The new taxon, P. pradeepianum shows a distinct variation on its fruit anatomy with its allied taxa ( Table 1).

Acknowledgements: —The authors express sincere gratitude to the authorities of Arya Vaidya Sala, Kottakkal for extending the facilities & TATA Trust Mumbai for the financial support. Sincere thanks are also due to Dr. N. Mohanan, JNTBGRI, Trivandrum and Dr. A.K. Pradeep, Department of Botany, Calicut University for their critical comments on its identity; Dr. N. Sasidharan, Mr. Sreejith P. E., Mr. Ahmedul Kabeer T. K., Mr. K.P. Vimal, Mr. M. G. Prasad and Mr. Shinoj, Department of Botany, Calicut University, for their help.

Figures

FIGURE 1. Colour images of Peucedanum pradeepianum sp. nov. A. Habit; B. Flowering twig with fruits; C. Natural habitat; D. Fruits; Mericarp cross-section E. P. pradeepianum; F. P. anamallayense. (Photos: A-D, KM Prabhukumar; E,F, VS Hareesh)

FIGURE 2. Peucedanum pradeepianum A. Habit; B. Upper leaf; C. Flowering twig; D. Flower; E. Bract; F. Bracteole; G. Stamen; H. Fruit; I. Mericarp cross-section. (Drawn from K. M. Prabhukumar 7590 by V.S. Hareesh)