Emilia lateritica P. Biju, Josekutty, Prasad, V.S.A. Kumar & Augustine, 2022

Biju, Punnakot, Josekutty, Elayanithottathil Joseph, Prasad, Karuvankoodelu Subrahmanya, Kumar, Venugopalan Nair Saradamma Anil & Augustine, Jomy, 2022, Emilia lateritica (Asteraceae), a new species from lateritic plateaus of Northern Kerala, India, Phytotaxa 556 (2), pp. 201-206 : 202-205

Emilia lateritica P. Biju, Josekutty, Prasad, V.S.A. Kumar & Augustine , sp. nov. ( Figure 1 )

Emilia lateritica is allied to E. sonchifolia (L.) Candolle (1834: 24) but differs from the latter in plant size (up to 12 cm vs. up to 90 cm), number of heads (1–4 vs. 5–8), number and extension of florets (4–10, extending much beyond the involucre vs. 40–65, equal or slightly exceeding the involucre), length of pappus (up to the middle of the corolla tube vs. slightly shorter than or equal to the corolla tube) and achene indumentum (hirsute throughout vs. hairy along angles). It is also allied to E. scabra Candolle (1834: 24) but differs in habitat (lateritic rocks vs. medium altitude grasslands), plant size (up to 12 cm vs. up to 70 cm), number of heads (1–4 vs. 6–8), number of florets (4–10 vs. 30–50), and achene indumentum (hirsute throughout vs. minutely hairy along angles).

Type:— INDIA. Kerala, Kasaragod District, Pandy , 35 m, 12°53’2684” N, 75°20’7595” E, 15 July 2021, P . Biju & Josekutty 8236 (holotype: MH!; isotypes: KFRI!, CALI!) .

Description:— Ephemeral erect annual herbs, ca 12 cm high. Stem unbranched, terete, 0.8–1 mm in diam., purplish-green, glabrous towards base, hirsute above; internodes up to 1 cm long. Leaves few, subopposite at base, alternate above, petiolate, estipulate; lamina deltoid, orbicular or ovate, 6–14 × 4–5 mm, apex obtuse or rounded, base cuneate or attenuate, not amplexicaulous, margins sinuate or lobate, recurved, pilose above, sparsely hirsute beneath, light green above, purplish beneath; midrib impressed above, raised beneath; lateral nerves indistinct; upper leaves sub sessile, basal leaves petiolate, petiole 3–16 mm long, light purplish, densely pilose, shallowly grooved above. Peduncles terete, 2–2.5 cm long, unbranched or rarely branched (branching lateral), sparsely pilose; bracts 1 or 2, distant, lanceolate, 1.5–2 × 0.4–0.5 mm, apex acuminate, entire, hirsute, brownish. Head urceolate at base, narrowed above, 7–8 × 1–1.3 mm, florets projecting well above (half the length of involucre), florets 4–10, 6–7 mm long, pink; involucral bracts 5, subequal, united to form urceolate cup, 5–7 mm long, slightly twisted above, sparsely glandular hispid; lobes slightly spreading, acute, 0.5–1 mm long, purplish; receptacle convex, ca. 1 mm across. Pappus many, up to the middle of the corolla tube, 2.5–3.5 mm long, barbellate, delicate, white. Corolla tubular, corolla tube narrowed below, slightly dilated above, pink, 3–4 mm long, glandular hairy; corolla lobes 5, spreading, 1–1.2 × 0.4–0.5 mm, linear-lanceolate, apex acute or round, recurved, margin minutely crenate-serrate, glabrous. Stamens 5, included, attached near the middle of tube; filaments slender, 0.6–0.8 mm long, glabrous; anthers syngenesious, linear-elliptic, 1–1.2 × 0.15–0.20 mm, creamy, glabrous; pollen grains spherical, spinulose. Ovary 1.8–2 × 0.15–0.2 mm, tubular or obscurely quadrangular, densely hispid; style ca 4 mm long, glabrous, extending beyond the corolla tube, pinkish above; stigma 2-lobed, lobes slender, 0.3–0.35 mm long, apex acuminate, light pink, minutely papillate. Achenes cylindrical to obscurely quadrangular, 2–2.2 mm long, densely hispid; ribs prominent, greyish brown to straw-coloured; pappus 3–4 mm long, erect or slightly radiating, barbellate, creamy silky white, persistent.

Phenology:— Plants appear with the onset of rainy season, start blooming from June and complete their life cycle by September.

Etymology: — The specific epithet is derived from the peculiar lateritic habitat of the new species, which is found along the western coast of Peninsular India.

Taxonomic notes:— The new species is most similar to E. sonchifolia in some vegetative and floral characters and shares the same habitat with the latter. However, they differ in several characters ( Table 1 ).

Distribution and ecology:— Emilia lateritica is discovered only on lateritic plateaus of Kasaragod District of Kerala, South India. The species is found growing on shallow soils on rocks which are generally Nitrogen-deficient. The plants are growing in clusters along with grasses and other forbs including Utricularia malabarica Janarthanam & Henry (1989: 84) , Polygala chinensis Linnaeus (1753: 704) , Isachne veldkampii Bhat & Nagendran (1983: 258) and Eriocaulon madayiparense Swapna et al. (2012: 19) . The allied species, E. sonchifolia is also found on these plateaus. It is quite larger and more robust than the new species and prefers to grow on deeper nutrient-rich soil. Other species of Emilia mostly prefer to grow on low to medium-altitude hills of Peninsular India.

Additional specimen examined (paratype):— INDIA. Kerala: Kasaragod District, Posadi , 260 m, 12°64’1311” N, 75°04’2526” E, 26 July 2020, P. Biju & Josekutty 9432 ( KFRI!) .

Conservation Status:— Lateritic plateaus on the Kerala and Konkan coasts of Peninsular India are often considered as neoendemic regions and harbour a large number of endemic species. The new species is found growing only in a few localities along the plateaus of Kasaragod District. The area is subject to laterite mining and rapid urbanization. The distribution of the species on other plateaus is not known and hence may be assessed as Data Deficient (DD) of IUCN (2019).

Figures

FIGURE 1. Emilia lateritica sp. nov.A. Habit; B. Variation in leaf morphology; C. Stem: enlarged view of a portion; D & E. Capitulum; F. Floret; G. Mature capitulum; H. Achene.