Figueiredo creeping-oxeyes (Wedelia figueiredoana) from Brazil associated with Wedelia bonplandiana

NEWS - Figueiredo creeping-oxeyes (Wedelia figueiredoana V.R.Bueno, sp. nov.) from the state of Ceará, Brazil, is reported as a new species morphologically associated with Wedelia bonplandiana and its conservation status is proposed as Critically Endangered.

Wedelia Jacq. is mainly found in the Neotropics, occasionally in the southern US and Tropical Africa. Brazil is a country with 89 occurrences of the species, 56 of which are endemic. During a field expedition in the municipality of Graça in February 2023, researchers found an unusual specimen.

W. figueiredoana is herbaceous in habit, prostrate, 0.15–0.3 m tall. Stems cylindrical, strigose to sparsely hirsute or densely hirsute, castaneous, internodes 0.84–6.7 cm long.

Leaves decussate, rarely reduced at the base, sessile; blades 2.25–10.3 × 0.25–1.05 cm, linear to narrow oblong, base attenuate, apex attenuate, often acute, hypodromous venation, often acrodromous basal, margins entire, flat; abaxial surface hirsute to densely strigose, veins hirsute to densely strigose, eglandular, adaxial surface hirsute to densely strigose, eglandular; olivaceous, concolorous to slightly discolorous, chartaceous.

Capitula solitaries, terminal, peduncle (1.85–) 5.3–13.2 cm long, sparsely hirsute to hirsute, often strigose to sparsely hirsute, eglandular. Capitula heterogamous, radiate; campanulate involucre, (5.3–) 6.7–9.5 mm × 6.7–12.7 mm.

Phyllaries 3-seriate; blades lanceolate, margins entire, flat, eglandular surfaces; outermost series apex acute or attenuate, densely hirsute to hirsute or densely hirsute to densely strigose, first series blades 9.4–12 × 1.9–2.3 mm, margin ciliate or not ciliate, olivaceous, foliaceous; second series blades 7.6–10.7 × 2.2–3.1 mm, margin ciliate or not ciliate, olivaceous or pale yellow to olivaceous, foliaceous or scarious with apex foliaceous; innermost series blades 5.5–7.6 × 1.6–2.6 mm, apex attenuate, sparsely hirsute to strigose, pale yellow to olivaceous, scarious with apex foliaceous or scarious.

Receptacle flat, holopaleaceous, paleae 6.7–8.9 × 2–2.6 mm, narrow elliptic or narrow oblong, apex acute, concave or conduplicate, pale yellow to yellow.

Ray florets 6–8, neutral, corolla ligulate, 10.3–14.3 mm long, tube 1.2–2.5 mm long, limb 9.1–12.3 × 6–6.3 mm, obovate or wide elliptic, apex 3-lobulate, 3–6 veins, tube pilose or glabrous, surface abaxial glabrous, surface adaxial glabrous, nerves sparsely pilose or glabrous, yellow.

Disc florets 25–40, monoclinous, corolla tubular, 4.8–6.2 mm long, tube 1.3–1.9 mm long, lobes 0.9–1.1 mm long, glabrous, yellow; anthers 2.2–3 mm long, apical anther appendages ovate, black; style arms 1–1.2 mm long, linear, yellow.

Cypselae 3.9–5.6 mm long, obovoid, flattened, densely sericeous, blackish, wings present throughout the pericarp, but apically pronounced, 0.04–0.4 mm long, yellow; pappus constrict at base, coroniform 0.5–0.6 mm long, 2-aristate, bitypic, monolength or bilength, 1.2–2.9 mm long, yellow.

W. figueiredoana morphologically resembles W. bonplandiana with leaf blade width 0.25–1.05 cm (vs. 1.5–2.6 cm), leaf blade linear to narrowly oblong (vs. elliptical to spatulate), 3-seriate involucre (vs. 2-seriate) and cypselae 3.9–4 mm long (vs. 6–7 mm).

The new species is a microendemic known only in one municipality in the state of Ceará: Graça. It grows in open areas containing ferruginous soils in the Cerrado enclave at 370–600 m elevation. This enclave is also in the Ibiapaba plateau, in Graça, Ipu, Ipueiras, Pacujá, Pires Ferreira and Reriutuba (municipalities of the state of Ceará).

The new species in testimonial hills and small inselbergs associated with the plateau, forming the Cerradão interspersed with open areas, rocky outcrops and ferruginous soils. This area is a transition zone between the Caatinga vegetation of the lowland areas to the humid and subhumid forests of the highlands.

Researchers propose the status of W. figueiredoana as Critically Endangered. The specimen was collected with flowers and fruits in February. The epithet “figueiredoana” is given in honor of Dr. Marlene Feliciano Figueiredo, a dedicated educator at Universidade Estadual Vale do Caraú (UVA).

Original research

Bueno VR, Rodrigues LS, Sousa FD, Souza IC, Marzinek J, Marques D (2024). Wedelia figueiredoana (Asteraceae, Heliantheae), a winged cypselae new species of Wedelia for Brazil. PhytoKeys 249: 37-49, DOI:10.3897/phytokeys.249.135699

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