Pedicularis rajeshiana Arti Garg, 2025

Garg, Arti, 2025, Pedicularis rajeshiana (Orobanchaceae), a new hemiparasitic species from Western Himalaya, India, Phytotaxa 702 (2), pp. 149-165 : 155-162

Pedicularis rajeshiana Arti Garg , sp. nov. ( Figs. 1–6 )

Type:— INDIA. Himachal Pradesh: Rohtang pass hill slopes 4390 m (32°21′28.4″ N, 77°13′01.0″ E), 5 th August 2019, Arti Garg 79520 (holotype CAL; isotype BSD) .

Perennial, delicate, erect or ascending, terrestrial herb, 4–6.5(–9) cm high (including inflorescence). Root rhizomatous, rhizome stout, 0.5–1 cm long, bifurcated at tip, branched diffusely into bunch of slender, dry, fibrous rootlets; rootlets 1–2 cm long, penetrating the roots of adjacent host plant forming haustorial interconnections. Stem herbaceous, solitary or 2–3 from root, unbranched, 3–4 cm long, slender, terete, slightly flexuous, erect or arching, reddish-purple, bifariously hairy. Leaves both radical and cauline, oblong or ovate-lanceolate, pinnatifid, with patch of woolly hairs present in pinnae sinuses, subcoriaceous. Radical leaves 3–7, arising from rhizome, petiolate, 1.3–2 cm long (with petiole); pinnae 5–7 paired, ovate, opposite, subopposite or alternate, distant, margins dentate, apex obtuse, mid-vein raised adaxially, surfaces glabrous with tuft of white woolly hairs in between pinnae sinuses, basal pinnae-pair isolated from other pairs; petioles 1.5–2 cm long. Cauline leaves single pair, or rarely 2-pairs, opposite, ovate to oblong, 4–7 mm long, petiolate; pinnae 3–4 pairs; petiole stout, 1–2 mm long, winged, glabrous. Inflorescence terminal, subcapitate, 2–7- flowered racemes, unbranched, 1.5–3 cm long, peduncled; peduncles bifariously hairy. Bracts attached at pedicel base, pinnatisect, elliptic-ovate, 4–6 × 5 mm, half smaller than or equal to the calyx, petiolate, coriaceous, mid-rib plicate; pinnae 3–4 pairs, margins shallowly wavy-lobulate, apex obtuse; petioles 1–1.3 mm long, glabrous outside, sparsely ciliate along midrib abaxially, with tuft of woolly hairs at pinnae sinuses. Flowers pedicellate, erect, 1.5–2 cm long (including pedicel), bracteolate; pedicels 1–1.2 mm long, glabrous, erect. Calyx 5-lobed, not cleft, obliquely-tubular, 5–6.5 mm long (including lobes), coriaceous; tube 4.5–5.5 × 2.5–2.8 mm, prominently 10-nerved with 5 stronger nerves alternating with 5 weaker nerves reaching lobe apices; mouth oblique, higher anteriorly, lower posteriorly, lowest side c. 5 mm long, highest side 6.5–7 mm long, glabrous outside, villous inside, tufts of white woolly hairs present at lobe sinuses; lobes unequal, erect, triangular to linear, 0.7–1.7 mm long, coriaceous, purple-green, margins entire, slight recurved exposing inner cilia; posterior lobe smallest, c. 0.7 mm long, subulate; lateral lobes ovate-elongate, c. 1.7 mm long, dentate, apex obtuse; anterior lobes deltoid, c. 1 mm long, margins wavy. Corolla pinkish-white with darker galea and white-tinged upper part of the corolla tube, throat and lower dorsal part of galea; tube cylindrical, 7.5–10 mm long, widened at mouth, one and half to less than two times as long as the calyx, sparsely puberulous and glaucous; galea stout, sessile, rostrate, slightly shorter than the summit of labium, white at base, dark pink above, erect from corolla tube for c. 3 × 1 mm then inflated near base and incurved for c. 5 mm length in antheriferous part in sickle shape, or incurved and angularly sub-contorted, tapering to a straight or curved, 5–6 mm long, stout beak constricted below apex then expanded for c. 1 mm length, beak-apex obliquely truncate, entire, obtuse; labium projected beyond the summit of galea, lobes spreading, 9–11 × 14–17mm, deeply incised almost up to base and adnate only at origin; mid-lobe obovate to spathulate, 10–11 × 3.5–5.5 mm, almost half narrower than the lateral lobes, projected 2.5–3.5mm beyond galea summit, apex obtuse; lateral lobes slight angularly-ovate or elliptic-orbicular, 8–9.9 × 9.5–11 mm, two or more times broader than the mid-lobe, nerves lacking or faintly visible, surface glabrous, all margins entire. Stamens inserted in upper half of corolla tube almost midway between the apex and middle of the tube at 3 levels ( Fig. 3C, E ), anterior pair c. 0.5mm lower than posterior pair—1 st filament at lowest point ( Fig. 3 Ea), 2 nd at 0.7mm above the 1 st ( Fig. 3 Eb), 3 rd at same level as the 2 nd ( Fig. 3 Ec) and 4 th at 0.7mm above 2 nd and 3 rd, the highest point, such that 1 st and 2 nd filaments are of anterior pair, 3 rd and 4 th are of posterior pair with 1 st filament at lowest and 4 th at highest point c. 1.4mm above the 1 st ( Fig. 3 Ed); filaments 9–9.5 mm long, very thin, thread-like, all glabrous; anthers elliptic, c. 1.5 mm long, basifixed, cells acute at both ends. Ovary ovate, 3–3.5 × 1.5 mm, apex obliquely acute; style 24–27 mm long, glabrous; stigma minutely globose, purple. Pollen grains bicolpate, prolate, exine 1 µm thick with crotonoid surface ornamentation, c. 21.5 × 15 µm in size having bilobed outline.

Flowering and fruiting:— July–October.

Distribution:— The new species is presently endemic to Rohtang in Himachal Pradesh of western Himalayas, India.

Habitat:— P. rajeshiana grows on the hill slopes of landscapes adjacent to the Manali-Rohtang National highway and eclipsed amongst the vegetation and grasses in partially shaded nooks and shadows of rocks and rock-boulders in humus-rich, damp or dry soils, at elevations 4390–4400 m asl, forming fragmentary population patches of 3–7 plants each, spreading in about 5002 meter area ( Fig. 1A ).

Etymology:— The specific epithet “rajeshiana ” is derived from the popular masculine name of Indian origin ‘Rajesh’ meaning “Lord of Kings”, to honour the undaunting support of the author’s husband Rajesh Garg, who not only motivated, but also planned and accompanied her field trips in the difficult terrains of western Himalayas having thwarting and unpredictably harsh climatic conditions, mainly in Rohtang and Sach pass regions and also helped in recording the present Pedicularis species in field.

Microhabitat: — Pedicularis rajeshiana displays typical hemiparasitic characters as it’s fibrous rootlets produce haustorial interconnections with those of the associated plant species growing in vicinity and forming a microhabitat ( Fig. 6 ). The microhabitat of Pedicularis rajeshiana comprised mainly of grassy and herbaceous species notably— Alchemilla sp. , Bistorta affinis (D.Don) Greene ( Polygonaceae ), Cortia depressa (D.Don) C. Norman ( Apiaceae ), Fragaria sp. , Geranium sp. , Lagotis sp. , Persicaria sp. , Plantago atrata Hoppe , Potentilla sp. , Ranunculus sp. , Saxifraga sp. , Trachydium roylei Lindl. ( Apiaceae ) and some members of Fabaceae , and Poaceae along with Bryophytes, Mosses and Ferns.

Innovative trait:— Two flowers having twin galeas were spotted. This innovative trait was never found earlier in this genus and suggests acquired, adaptive and evolutionary transition for more precise pollination through predator deception.

Conservation status: — Pedicularis rajeshiana is presently known only from type locality, Rohtang in Himachal Pradesh (Western Himalayas), India. During type collection in August 2019, about 185 mature individuals were recorded in 35 counted population patches. Horse grazing and tourist movement was recorded as an operational threat ( Figure 1B ) in this area. But presently, based on the limited distributional range and population strength of mature individuals, the species is provisionally assessed under criteria D (endangered) of the IUCN (2019) guidelines and calls for survey to locate more populations.

Figures

FIGURE 1.A: Landscape of Rohtang showing scattered population patches (in stars) of Pedicularis rajeshianaArti Garg (Ro: Rocks and Rock boulders). B. Grazing in the landscape. C, D, E: Three different populations of P. rajeshiana.

FIGURE 2. Field photographs of Pedicularis rajeshiana Arti Garg A., habit and habitat with beak enlarged (inset Fig. a). B. Habit with cauline leaf pair showing bifariously hairy stem. C. Flower with twin galea. D. Flowers with sickle shaped galea and deeply incised labium lobes. E. 5-flowered inflorescence. F. Flower enlarged showing ciliate calyx lobe, bracts and stout beak with emarginate apex.

FIGURE 3. A. Habit (one specimen of Isotype Pedicularis rajeshiana Arti Garg 79520) with arching stem; B–D, F–K: Illustrations drawn with scale. B. Flower in lateral view; C. Longitudinal Section of flower with intact labium; D. Calyx split open; E. Microphotograph of dissected galea, split open to show stamen insertion on corolla tube; F. Labium; G. Bigaleate flower; H. Bract; I–J. Galea showing beak, I. Lateral view; J. Front view; K. One pair of stamens.

FIGURE 4. Pollen micrographs.A–C: Pedicularis rajeshiana Arti Garg; A. SEM equatorial view with one colpus; B. LM equatorial view with 2 colpi; C. SEM showing crotonoid exine. D–G: P. porrecta Wall. ex Benth.; D. SEM equatorial view of 2 grains showing colpus and granular colpi margins; E. LM equatorial view with 2 fused colpi; F. LM showing outline in polar view; G. SEM showing exine pattern. H–K: P. heydei Prain; H. SEM equatorial view with one colpus; I. LM obliquely polar view showing outline; J. LM equatorial view showing colpi fused at one pole; K. SEM showing exine pattern and colpus margin.

FIGURE 5. Pedicularis rajeshiana Arti Garg sp. nov. Arti Garg 79520 (holotype CAL).

FIGURE 6. Isotype image showing hemiparasitism in Pedicularis rajeshiana Arti Garg sp. nov. Arti Garg 79520 (Isotype: BSD) with root haustorial connections (encircled) with other plants.