Stellaria rajbhandarii Kafle & G.Parmar, 2024

Kafle, Rashika, Pandey, Neelam & Parmar, Gaurav, 2024, Stellaria Rajbhandarii (Caryophyllaceae), A New Species From Nepal And Resurrection Of Stellaria Neotomentosa, Phytotaxa 671 (3), pp. 259-270 : 260-267

Stellaria rajbhandarii Kafle & G.Parmar , sp. nov.

Type:— NEPAL. Bagmati Province, Lalitpur district, Godawari , 1530 m, 5 May 2023, Kafle, Poudel & Parmar RKG75 (holotype KATH164550 !; isotypes KATH164551 !, KATH164552 !, TUCH!) ( Fig. 1 ) .

Diagnosis: —Morphologically, Stellaria rajbhandarii is similar to S. nepalensis but differs in having lime green appearance; mostly ascending habit; densely villous; leaves linear-lanceolate, base cuneate; flowers 12–14 mm across; petals equal to sepals, lobes oblong, lobes apex distinctly incised, ribs inconspicuous; capsule 4/5 shorter than sepals; seeds orbicular to suborbicular, 0.6–0.8 mm, testa cell margin dentate and sinuate, arms 4–8 in a zigzag pattern, subarms 2–3 branched, curvature of outer periclinal wall convex [vs. pale green appearance, mostly prostrate habit, subglabrous; leaves ovate to broadly ovate, base subcordate to rounded; flowers 14–18 across; petals 1/3 longer than sepals, lobes elliptic, lobes apex obtuse, ribs conspicuous (3–7); capsule 1/2 as long as sepals; seeds suborbicular to obovate, 0.8–1.1 mm, testa cell margin dentate, sinuate and deeply armed, subarms obscure, curvature of outer periclinal wall convex with compact rugose elevation in the latter ( Fig. 2 )].

Description: —Perennial herbs. Roots branched, rooting at basal nodes of rhizome, simple lateral roots. Lime green with white uniseriate multicellular eglandular villous. Stems mostly ascending to decumbent, branched at base or simple, swollen at nodes, pale green, 10–60 cm, internodes 2.5–8 cm, terete, villous. Leaves subsessile to sessile; petioles subsessile up to 2.5 mm, hairy; leaf blades linear-lanceolate to lanceolate, 10–30(–35) × 3–12 mm, base cuneate to broadly cuneate, apex acute to shortly acuminate, margins slightly thick, entire and hairy, abaxially hairy including midvein, adaxially subglabrous or glabrous, midvein conspicuous, venation closed. Flowers 3–10, in axillary cymes, lax, 10–14 mm across, nectars present. Peduncles 2.5–8 cm, villous. Bracts scarious in pair, ovate-lanceolate, 2.5–6 × 1.2–1.6 mm, base broadly cuneate, apex acute, glabrous, veins inconspicuous. Pedicels 1–3(–3.5) cm, densely villose. Sepals 5, oblong-lanceolate to lanceolate, 5–7 × 1.4–1.6 mm, base rounded, slightly loose at the edge of base, apex narrowly acuminate, margins broadly scarious, both surfaces glabrous, 3-conspicuous ribs. Petals 5, equal to sepals, sometimes slightly shorter than sepals; lobes oblong-elliptic, 5–7 × 1.2–1.6 mm, 2-cleft at base, apex usually notched, ribs inconspicuous. Stamens 10, 5 +5 arrangement in an alternate manner, 4–5.5 mm; filaments white, 3.5–4.5 mm, filiform, slightly dilated at base, nectar at base; immature anthers pale pink to red-pink, matured one’s purple-black to brown-black, 0.7–1 mm. Ovary pale green, narrowly ovoid, 1.8–2.5 mm; styles 3, white, 2.5–3 mm long, apex curved outwardly. Capsule yellow-green, narrowly ovoid, subequal or 4/5 shorter than persistent sepals, 4.5–5 mm, 6- valved; valves narrowly lanceolate, acute apex. Seeds 2–4(–7), reddish brown, orbicular to suborbicular, 0.6–0.8 mm, rugose ( Fig. 1 ).

Description (micromorphology):—Seeds testa cell shape is elongate-rectangular, testa cell margin is dentate and sinuate with 4–8 arms arranged in a zigzag pattern and having 2–3 branched subarms, and the curvature of the outer periclinal wall is convex.

Etymology:— The specific epithet “ rajbhandarii ” refers to Prof. Sangeeta Rajbhandary, who has made an immense contribution to the taxonomy of Nepalese vascular plants in a span of over 30 years.

Phenology:— April to July.

Habitat and distribution:— It is found as a weed, mostly in moist and shady places or in open canopy in the grasslands or the edge of crop fields, lawns, roadsides, ditches, or riverside at an elevation range of 1450–1550 m. It is currently only known from the Godawari area of Kathmandu Valley, Central Nepal ( Fig. 3 ).

Conservation status:— It is widely observed in several localities in Godawari, Lalitpur district, Kathmandu Valley, Nepal. It grows naturally in the forests nearby, in the protected areas (including the National Botanical Garden), and along the roadsides. It was found in patches, with a few to more than 250 individuals per patch. Despite the fact that the species has only been found in the Godawari area, its potential presence in other areas cannot be ignored. Therefore, in the absence of a thorough investigation in other regions, the species has been considered as data deficient (DD) based on the categories and criteria of IUCN (2012).

Notes:— The stems are lime green, and the flower has a strongly scented or sweet aroma in the population of Stellaria rajbhandarii . However, stems mostly have purplish brown tinges at internodes and nodes, and flowers are almost scentless or slightly scented in the population of S. nepalensis . Stellaria rajbhandarii is commonly found growing in the Godawari region along with S. patens D.Don. They share some morphological similarities, and therefore, the previous studies have misidentified this new species as S. patens . A detailed comparison to distinguish S. rajbhandarii from the two taxa of S. patens and S. nepalensis is presented in Tables 1 & 2 and Fig. 4 .

Additional specimens examined (paratypes):— NEPAL. Bagmati Province, Lalitpur district, Godawari, National Botanical Garden , 1515 m, 13 April 2003, Joshi 505 ( KATH!) ; Lalitpur district, Godawari, 1550 m, 13 April 2007, Ghimire 072 ( KATH!, 2 sheets: KATH086365 , KATH086367 ) ; Lalitpur district, Godawari, Satdobato– Godawari Road , 1470 m, 26 May 2021, Kafle RKG01 ( KATH!) ; Lalitpur district, Godawari , Satdobato – Godawari

Road, 1475m, 26 May 2021, Kafle & Pandey RKG2 (KATH!); Lalitpur district, Godawari, 1472 m, 29 April 2022, Kafle RKG54 (KATH!); Lalitpur district, Godawari, 1515 m, 11 May 2022, Kafle RKG65 (KATH!, TUCH!); Lalitpur district, Godawari, 1450 m, 12 July 2023, Kafle & Parmar RKG83 (KATH!).

rajbhandarii .

Stellaria neotomentosa M.Mizush. ex H.Ohba in Ohashi, Fl. E. Himal., 3 rd. rep.: 33. f. 7 (1975). Type:— NEPAL. Bagmati Province, Lalitpur district, Godawari–Phulchowki (2100–3000 m), 29 May 1969, Hara, Kurosawa & Ohashi 70027 (holotype TI00021536!, isotype BM000521531!) ( Fig. 5 ).

Description: —Perennial herbs. Roots branched, rooting at basal nodes of rhizome, sparse lateral roots. Basil green with white dense uniseriate multicellular eglandular pilose. Stems prostrate or decumbent, branched at base or simple, swollen at nodes, green with light purple-brown tinges at nodes and internodes, 10–30(–35) cm, nearly 4-angled, dense white pilose. Leaves subsessile to sessile; petioles up to 3 mm, pilose; leaf blades ovate to broadly ovate, 5–20(–25) × 3–15 mm, base rounded to subcordate and slightly clasping, apex acute, margins entire and hairy, both surfaces divergent pilose, midvein conspicuous, venation closed. Flower 1–3(–5), in axillary or rarely terminal cymes. Peduncles 1.5–3 cm, pilose. Bracts scarious in pair, ovate-lanceolate, 3.5–5.5 × 1–2 mm, base broadly cuneate, apex acuminate, margins broadly scarious, sometimes abaxially pilose or subglabrous, adaxially glabrous, veins inconspicuous. Pedicels 1–3(– 3.5) cm, densely pilose. Flowers 12–16(–20) mm across, slightly scented, nectars present. Sepals 5, lanceolate, 4.5– 6(–7) × 1.6–2.2 mm, base rounded, slightly loose at the edge of base, apex narrowly acute, margins broadly scarious, subglabrous in flower, pilose on abaxial surfaces of persistent sepals of capsule, adaxially glabrous, 3-conspicuous ribs. Petals 5, 1/3 longer than sepals, rarely equal to sepals; lobes oblanceolate-oblong, 6–8(–10) × 1.5–2 mm, 2- cleft at base, apex emarginated, 3-conspicuous ribs. Stamens 10, 5 +5 arrangement in an alternate manner, 4–5 mm, arranged in a ring-shaped glandular disc, more or less equal in size; filaments white-pink, 3.5–4.5 mm, filiform, slightly dilated at base, glands at base; immature anthers red-pink, matured one’s purple-black, 0.5–0.7 mm. Ovary pale green, narrowly ovoid, 2–3 mm; styles 3, white, 2–3 mm long, apex curved outwardly. Capsule yellow-green, ovoid, 1/4 longer than persistent sepals, 7–8 mm, 6-valved; valves lanceolate, acute apex. Seeds numerous, brown, obovate to broadly elliptic, 1–1.35 mm, rugose ( Fig. 5 ).

Description (micromorphology):—Seeds testa cell shape is elongate-rectangular, testa cell margin is slightly dentate and arms obscure, and the curvature of the outer periclinal wall is convex with dome-shaped/rugose elevation.

Phenology:— May–August.

Habitat and distribution:— This species is found at the margins of broadleaved forests of Quercus and Castanopsis species, as well as evergreen temperate forest trails (2200–2650 m). It is distributed in the East Himalaya, the Tibetan Plateau, and Central Nepal ( Fig. 3 ).

Note:— According to protologue ( Ohba 1975), sepals are about 1.2-fold longer than petals in S. neotomentosa . However, in the holotype and the recent observed specimens, the sepals have been found to be 1/3 shorter than the petals. Additionally, the size of sepals can elongate by 1.2–1.6 times in capsules.

Additional specimens examined:— NEPAL. Central Nepal: Bagmati Province, Kabhrepalanchowk district, Mount Phulchowki , 2620 m, 27°33ʹN 85°24ʹE, 16 May 2001, Yonekura 7674 ( KATH!) ; Kathmandu district, Deurali, Way to Chandragiri hills, 2243 m, 27˚39ʹ28ʺN 85˚13ʹ02ʺE, 18 June 2023, Kafle, Ghimire, Poudel & Thapa RKC1 ( KATH!) ; Lalitpur district, Godavari (1600)— Phulchauki (2500), 23 June, 1967, Hara, Kanai, Murata, Ohashi, Tanaka & Yamazaki 10006098 ( TI!) ; Lalitpur district, Godavari (1600)— Phulchauki (2500), 23 June, 1967, Hara, Kanai, Murata, Ohashi, Tanaka & Yamazaki 10006143 ( TI!) ; Lalitpur district, Godavari–Phulchoki, South of Kathmandu , 2200 m, 28 May 1972, Ohashi & Ohba 726417 ( KATH!, TI!) ; Lalitpur district, Phulchowki (1350–2700 m), 2200 m, 30 June 1983, Ohba, Kanai, Wakabayashi, Suzuki & Akiyama 8330042 ( KATH!, TI n.v.) ; Lalitpur district, Phulchowki , 2518 m, 27.5755°N, 85.3992°E, 9 June 2021, Kafle, Pandey, Poudel, Nagarkoti & Marpa RK 235 ( KATH!, TUCH!) .

Figures

FIGURE 1. Stellaria rajbhandarii. A. Habitat, B. Inflorescence, C. Flower, D. Sepals (abaxial & adaxial), E. Petal, F. Stamens, G. Pistil, H. Capsule and valve, I. Seed (photographs: A–G by Y.B Poudel, H by R. Kafle and I by P. Bhandari).

FIGURE 2. Stellaria nepalensis. A. Habit, B. Habitat, C. Leaves (adaxial & abaxial), D. Flower, E. Sepals (adaxial & abaxial), F. Petal, G. Stamens, H. Pistil, I. Capsule and valve, J. Seed (photographs: A–I by R. Kafle and J by P. Bhandari).

FIGURE 3. Distribution map of Stellaria neotomentosa, S. nepalensis and S. rajbhandarii.

FIGURE 4. Seed morphology examined by Scanning Electron Microscopy. Stellaria neotomentosa (A–C; specimen RKC1 at KATH from Nepal, Bagmati, Kathmandu, Deurali). A. Seed, B. Enlarged view of seed, C. Pedicel of capsule, Stellaria nepalensis (D–F; specimen RS75 at KATH from Nepal, Gandaki, Kaski, Nayapul). D. Seed, E. Enlarged view of seed, F. Pedicel of capsule, Stellaria patens var. ovatifolia (G–I; specimen RKG81 at KATH from Nepal, Bagmati, Lalitpur, Godawari). G. Seed, H. Enlarged view of seed, I. Pedicel of capsule, Stellaria patens var. patens (J–L; specimen E5 at KATH from Nepal, Koshi, Dhankuta). J. Seed, K. Enlarged view of seed, L. Pedicel of capsule, Stellaria rajbhandarii (M–O; specimen RKG83 at KATH from Nepal, Bagmati, Lalitpur, Godawari). M. Seed, N. Enlarged view of seed, O. Pedicel of capsule (photographs by P. Bhandari).

FIGURE 5. Stellaria neotomentosa. A. Habit, B. Enlarged stem showing vestiture, C. Leaves (adaxial & abaxial), D. Flower, E. Sepals (abaxial & adaxial), F. Petal, G. Stamens, H. Pistil, I. Capsule and valve, J. Seed (photographs: A–I by R. Kafle and J by P. Bhandari).