Paepalanthus linearilaminatus L. E. F. Silva 2026, sp. nov.

Paepalanthus linearilaminatus L.E.F.Silva sp. nov. urn:lsid:ipni.org:names:77371912-1 Figs 6–7 Diagnosis Paepalanthus linearilaminatus sp. nov. may be segregated from the P. trichophyllus complex by its linear leaves, which are small, recurved to deflexed and also by its oblanceolate floral bracts. Etymology The specific epithet ʻ linearilaminatus ' is derived from the Latin words ʻ linearis ' (ʻlinear') and ʻ lamina ' (ʻblade' or thin ʻsheet'), referring to the distinct morphology of the leaves, which are narrow, elongated, and linear in shape, a characteristic that differentiates the species from other within the group. Type material BRAZIL – Bahia • Piatã “ Estrada para Três Morros, acessada pela BA-560. Estrada de terra na primeira bifurcação às esquerda, sentido Três Morros, campo ca 2 km a partir da estrada principal, próximo a uma fazenda ”; 13°03′44″ S, 41°53′02″ W; 1431 m; 8 Jul. 2021; fl; W.L. Picanço 561; holotype: R [R253469]!; isotypes: HUEFS!, NY!, P!, RB!, SPF!. Other material examined BRAZIL – Bahia • Barra da Estiva; 23 Mar. 1980; fl.; R.M. Harley 20814; CEPEC, K, SPF • Barra da Estiva; 19 Jul. 1981; fl.; A.M. Giulietti et al. 1356; K, SPF • Mucugê; 6 Feb. 1974; fl.; R.M. Harley et al. 16066; CEPEC, IPA, K, MO, U, US • Piatã; 20 Aug. 1981; fl.; L. Coradin et al. 4369; CEN • Piatã; 15 Feb. 1987; fl.; R.M. Harley et al. 24316; HUEFS, K • Piatã; 14 May 1992; fl; W. Ganev 287; HUEFS • Piatã; 5 Nov. 1996; fl.; H.P. Bautista et al. 4074; ALCB, CEPEC, HUEFS, K, SPF • Piatã; 21 May 1999; fl.; V.C. Souza 22996; ESA • Piatã; 29 Jul. 2017; fl.; N. Roque et al. 4966; ALCB, HVC • Rio de Contas; 21 Mar. 1977; fl.; R.M. Harley et al. 19790; CEPEC, IPA, K, MBM, P, SP, SPF, UEC, US • Rio de Contas; 15 May 1983; fl.; G. Hatschbach 46408; INPA, US • Rio de Contas; 20 Feb. 1987; fl.; R.M. Harley et al. 24516; K, SPF • Rio de Contas; 6 Nov.1988; fl.; R.M. Harley et al. 25929; HUEFS, K, SPF • Rio de Contas; Mar. 1997; fl.; A.M. Giulietti & R.M. Harley 4013; BOTU, HCF, HUEFS, K, LAG, R, SORO, UB • Rio de Contas; Mar. 1997; fl.; A.M. Giulietti & R.M. Harley 4015; HUEFS, K, R • Rio de Contas; 4 Jan. 2003; fl.; R.M. Harley et al. 54552; HUEFS • Rio de Contas; 27 Mar. 2021; fl.; D.C. Zappi et al. 5169; HUEFS • Rio de Contas; 10 Sep. 2021; fl.; R.M. Harley et al. 58809; HUEFS. Description Perennial herbs, solitary, with an erect and self-supporting habit, 18.8–40.7 cm tall; rhizome present, usually conspicuous, aerial stem 5–19.2 cm long, sparsely pilose, unbranched or branched, internodes 1–2 mm long. Leaves persistent, arranged along the stem, chartaceous, rigid, linear, light green to brownish when old, recurved to deflexed, amplexicaul, 0.5–1.1 × 0.08–0.19 cm, pilose, margins involute and hirsute at the base and pilose distally, apex acute. Spathes ca 3 × as long as the leaves, glabrous, apex glabrous and acute. Scapes 1−10 per branch, arranged in a terminal umbelliform inflorescence or solitary, 11.9– 28.2 cm long, glabrous. Capitula hemispherical to globose, white-villous, 3.5–7 mm in diam.; involucral bracts in 3−5 series, obovate, castaneous, concave-convex, ca 2 mm long, pilose to glabrescent distally, margin ciliate, apex obtuse to rounded; receptacle hemispherical, pilose. Flowers dimerous; floral bracts oblanceolate, castaneous, concave-convex, ca 1.5 mm long, pilose distally, margin ciliate, apex obtuse or rounded. Staminate flowers 1–1.8 mm long; sessile or with pedicel ca 0.2 mm long, pilose; sepals 2, free, obovate, castaneous, ca 1.5 mm long, pilose distally to glabrescent, ciliate to glabrescent towards the obtuse apex; anthophore fleshy, elongate; corolla fused into a tube, hyaline, membranaceous, ca 1.5 mm long, glabrous; stamens ca 1.8 mm; anthers 2, exerted, ca 0.5 mm long. Pistillate flowers ca 2.5 mm long, sessile or with pedicel 0.3 mm long; sepals 2, fused at the base, oblong-obovate, castaneous, ca 2.5 mm long, sparsely pilose to glabrescent distally, margin ciliate to glabrescent toward the rounded apex; petals 2, free, elliptic, light castaneous to hyaline, ca 2 mm long, pilose distally on the abaxial surface, margin ciliate toward the obtuse or rounded apex; gynoecium 2 mm long, stigmatic branches 2, bifid at the apex, slightly longer than the nectariferous branches, staminodes 2, scale-like. Fruit a loculicidal capsule. Seeds not seen. Distribution, habitat and ecology Paepalanthus linearilaminatus sp. nov. is restricted to the state of Bahia (Fig. 3). The species is found in the Serra das Almas Municipal Park in the municipality of Rio de Contas, which hosts the largest population of individuals. It is also found within in Chapada Diamantina National Park. Additional records have been documented in remnants of native vegetation in the Serra da Tromba, Abaíra, Piatã, and the Serra do Sincorá in Mucugê. The species is found in rupestrian fields, predominantly in sandy soils, frequently waterlogged, and directly exposed to sunlight. Flowering specimens have been recorded in most months of the year: January, February, March, May, July, August, September, and November. Preliminary conservation assessment The species is protected within the Serra das Almas Municipal Park (BA) and the Chapada Diamantina National Park (BA). With an EOO of 3 138.849 km 2 and an AOO of 20 000 km 2, the species is suggested as Endangered: EN B1ab(iii). Its distribution is highly fragmented and restricted to the Chapada Diamantina, where typical Caatinga and Cerrado rupestrian fields formations predominate, one of the most threatened domains, exposed to severe pressures such as recurrent fires and widespread replacement of native vegetation by pastures and monocultures. Although it occurs in protected areas, these regions do not provide complete protection against frequent wildfires, which are often intensified by agricultural activities. Such threats may compromise its viability in the medium to long term. Taxonomic remarks Specimens belonging to the new species were previously misidentified as Paepalanthus trichophyllus due to shared traits, such as elongated stems, leaves arranged along the stem, hemispherical to globose capitula and castaneous involucral bracts, and dimerous flowers. Comparative analysis reveals diagnostic traits when populations of both species are compared. From the specimens of P. trichophyllus occurring in the type locality in São João del-Rei, P. linearilaminatus sp. nov. can be distinguished by having leaves 0.5–1.1 × 0.08–0.19 cm (vs 1.57–2.3 × 0.19–0.32 cm); glabrous spathes (vs pilose) with glabrous apex (vs pilose), glabrous scapes (vs densely pilose), floral bracts ca 1.5 mm long (vs 2 mm long), sepals and petals of staminate flowers ca 1.5 mm long (vs 2 mm long), pistillate flowers ca 2.5 mm long (vs 3 mm long) with sepals ca 2.5 mm long (vs 3 mm long) and light castaneous to hyaline petals ca 2 mm long (vs cream-colored to golden, 2.5 mm long), gynoecium ca 2 mm long (vs 3 mm long), and stigmatic branches slightly longer than the nectariferous branches (vs ca 1 mm longer than the nectariferous branches). When compared to the morphotype of Paepalanthus trichophyllus found in Itutinga, P. linearilaminatus sp. nov. is distinguished by its glabrous spathe (vs pilose) with glabrous apex (vs pilose), glabrous scapes (vs densely pilose), sepals and petals of staminete flowers ca 1.5 mm long (vs 2 mm long), pistillate flowers ca 2.5 mm long (vs 2 mm long) with sepals ca 2.5 mm long (vs 2 mm long) and elliptic petals ca 2 mm long (vs obovate, 1.5 mm long), and gynoecium ca 2 mm long (vs 1.5 mm long). Compared to the morphotype from Serra da Canastra National Park, P. linearilaminatus exhibits stems 5–19.2 cm long (vs 0.8–2 cm long), amplexicaul, recurved to deflected leaves with involute margin (vs patent, sessile, margin straight when the stem is short and restricted to rosette), pistillate flowers ca 2.5 mm long (vs 2 mm long) with sepals ca 2.5 mm long (vs 2 mm long) and petals ca 2 mm long (vs 1.5 mm long), gynoecium ca 2 mm long (vs 1.5 mm long), and stigmatic branches slightly longer than the nectariferous branches (vs ca 0.5 mm longer than the nectariferous branches). The species also shares morphological similarities with the sympatric Paepalanthus strictus, particularly in having leaves arranged along the stem, hemispherical to globose capitula and castaneous involucral bracts, and dimerous flowers. However, P. linearilaminatus sp. nov. can be distinguished by its linear and pilose leaves (vs lanceolate or subulate, hirsute to lanuginous) with hirsute margin at the base and pilose distally (vs hirsute to lanuginous all over the margin), obovate involucral bracts (vs spatulate) with obtuse or rounded apex (vs acuminate), oblanceolate floral bracts ca 1.5 mm long (vs linear, 2 mm long), sepals and petals of staminate flowers ca 1.5 mm long (vs 2 mm long), pistillate flowers ca 2.5 mm long (vs 3 mm long) with sepals ca 2.5 mm long (vs 3 mm long).