Stellaria mcclintockiae V. S. A. Kumar, Sindhu Arya, V. Suresh, Sojan & Alen Alex, sp. nov.
Creators: name: Arya, Sindhu
name: Kumar, Venugopalan Nair Saradamma Anil
name: Sojan, Jose
name: Philip, Alen Alex
name: Suresh, Veerankutty
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Caryophyllales
Caryophyllaceae
Stellaria
Stellaria mcclintockiae

description: Stellaria mcclintockiae V.S.A.Kumar, Sindhu Arya, V. Suresh, Sojan & Alen Alex sp. nov.
Type: — INDIA. Kerala: Palakkad district, Nelliyampathy, along the muddy slopes, 1200 m a.s.l., 10°30'06.1"N 76°39'08.9"E, 20 October 2019, Suresh & Arya 1609 (holotype UCBD!, isotype UCBD!).
Diagnosis: — Stellaria mcclintockiae is similar to the members of the Stellaria media group and differs from the various species with respect to characters of bracts, sepals, petals, pollen morphology and seed surface architecture (see Table 1).
Description (macromorphology): —Annual herbs, 12.0– 15.5 cm. Stem 10–14 cm tall, prostrate to ascending or erect, terete, basally branched, sparsely pubescent towards the base, nodes prominent, roots arises from the nodes, internodes ca 3 cm, with a single line of trichome. Stipules absent. Leaves petioled (petiole 1.5–3.0 cm long), with blade oblong-ovate (1.5–3.2 × 1.2–2.5 cm), margin entire, often wavy, apex acuminate, base obliquely cordate to reniform, abaxially midvein prominent, adaxially midvein impressed, margin shortly ciliate. Inflorescence terminal or axillary solitary flowers; zygomorphic, bracts lanceolate, green, pubescent on outer surface, 0.6–0.8 mm, bracteole ovate 0.2 mm. Sepal lanceolate-often oblong (1.0–1.5 × 0.4–0.8 mm), outer surface densely pubescent, green. Petal 5, exceeding the length of calyx, dimorphic lower petal broadly oblong-lanceolate, fused towards the base (2.0–2.2 × 0.5–0.8 mm), base clawed, apex round; upper petals slightly short (1.3–1.5 × 0.8–0.9 mm), lanceolate, fused from mid region, base cordate, apex fimbriate. Stamen 5–8 shorter than petals. Ovary broadly ellipsoid-ovoid; styles 3, linear. Capsule elongate, double the persistent sepals, 6-valved to base. Seed 2–6, black-brown (Figs. 2–3).
Description (micromorphology): —Pollen grains spheroidal, pantoporate, 12.56–13.34 µm with 8–10 visible frequency of pores. Pore margin or aperture is faintly demarcated. Size of pore 2.5–3.6 µm. The surface is microechinate. Echines blunt or appear like dots that joins to form a reticulate appearance. Ektexinous bodies present inside the pore, minute, 2 or 3, free.
Seeds reniform with base circular measuring ca. 0.657 –0.965 mm × 0.754 –0.865 mm. Margin wavy, tubercles short, more or less appressed; basal extension arms long, irregular and more compact as well as interlocked. Papillae are scanty on the upper part of their surface but more along the basal arms (Fig. 4).
Etymology:— The species is named in honor of Barbara McClintock, the Nobel laureate for her work on mobile genetic elements.
Habitat, distribution and phenology:— Stellaria mcclintockiae is known only from Nelliyampathy hills of Palakkad district at an elevation of 1250–1400 m a.s.l. It grows along the muddy slopes with 40–50 scattered individuals per population. Each population spreads over an area of less than 1 m 2. Flowering and fruiting times are May to September (Fig. 5).
Conservation status:— The plant propagates mainly through vegetative propagation. Number of individuals is very few and prone to severe grazing and stamping of elephants. Following the IUCN Red list criteria (IUCN 2022), Stellaria mcclintockiae is assessed as Critically Endangered (CR) in the category [B2a,b(v)].
Additional specimens examined (paratypes): — INDIA: Kerala: Palakkad District, Nelliyampathy, 1200 m, 10°30'06.1"N 76°39'08.9"E, 19 November 2022, Suresh & Sojan 2311 (UCBD); ibidem, 30 November 2022, Alen 2354 (UCBD).
description: Published as part of Arya, Sindhu, Kumar, Venugopalan Nair Saradamma Anil, Sojan, Jose, Philip, Alen Alex & Suresh, Veerankutty, 2024, Stellaria mcclintockiae (Caryophyllaceae) a new species from Kerala, India, pp. 55-65 in Phytotaxa 645 (1) on pages 57-62, DOI: 10.11646/phytotaxa.645.1.5, http://zenodo.org/record/13214862