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

Paepalanthus rollimae L.E.F.Silva sp. nov. urn:lsid:ipni.org:names:77371913-1 Figs 8–9 Diagnosis The new species is primarily distinguished by its recurved leaves, which are broader at the median portion, elliptical or elliptical-lanceolate in shape, pubescent, and have a rounded apex. These leaves are thick, with margins hirsute at the base and pubescent distally, while the acuminate to rounded apex further enhances its distinctiveness. Additionally, the species is characterized by a pubescent stem, discoid and white-villous capitula sharply contrasting with a dark brown involucral bracts at the basal portion, oblong or oblong-ovate involucral bracts, and oblong sepals in pistillate flowers. Etymology The new species is named in honor of the botanical researcher Isis Rollim, for her longstanding support of my Eriocaulaceae studies, article reviews, and species photographs. Type material BRAZIL − Goiás • Alto Paraíso de Goiás, “trilha para a Fazenda Água Fria ”; 14°05′39″ S, 47°30′19″ W; 7 Apr. 2019; fl.; L.E.F. Silva et al. 141; holotype: R [R255104]!; isotypes: CEN!, NY!, P!, RB!, SPF!. Other material examined BRAZIL − Goiás • Alto Paraíso de Goiás; 4 Feb. 1990; fl.; M.M. Arbo et al. 3592; HRCB, K, MBM • Alto Paraíso de Goiás; 24 May 1993; fl.; I.V. Lima 107; HEPH • Alto Paraíso de Goiás; 20 Jul. 1994; fl.; M. Aparecida da Silva et al. 2184; IBGE, SPF • Alto Paraíso de Goiás; 7 Sep. 1994; fl.; M. Aparecida da Silva 2283; SPF • Alto Paraíso de Goiás; 26 Apr. 1998; fl.; C.B.R. Munhoz et al. 715; HEPH, HUEFS • Alto Paraíso de Goiás; 26 Apr. 1998; fl.; C.B.R. Munhoz et al. 724; HEPH • Alto Paraíso de Goiás; 8 May 2000; fl.; G. Hatschbach 70681; BHCB, COR, HEPH, MBM, PACA-AGP • Alto Paraíso de Goiás; May 2002; fl.; V.L.C.R. Uliana et al. 648; CEN, ESA, HTO, IBGE, RB, SP, SPF, UB, UEC, UFG • Alto Paraíso de Goiás; 22 May 2008; fl.; J.M. Silva et al. 6652; MBM • Alto Paraíso de Goiás; 19 Mar. 2009; fl.; M. Trovó et al. 456; B, HRCB, R, RB, SPF, UB • Alto Paraíso de Goiás; 22 Mar. 2012; fl.; M.T.C. Watanabe et al. 238; SPF • Alto Paraíso de Goiás; 5 Apr. 2012; fl.; A.G. Amaral et al. 2741; HUEFS, UB • Alto Paraíso de Goiás; 13 Mar. 2015; fl.; A.L. Silva 7; HRCB • Alto Paraíso de Goiás; 11 Apr. 2017; fl.; J.F. Carrión 1812; HUEFS • Alto Paraíso de Goiás; 14 Nov. 2017; fl.; M.L.O. Trovó & L.M. Borges 695; CEN, OUPR • Alto Paraíso de Goiás; 9 May 2018; fl.; M.L.O. Trovó et al. 777; CEN, OUPR • Alto Paraíso de Goiás; 7 Apr. 2019; fl.; L.E.F. Silva et al. 145; R • Alto Paraíso de Goiás; 7 Apr. 2019; fl.; L.E.F. Silva et al. 147; R • Alto Paraíso de Goiás; 8 Apr. 2019; fl.; L.E.F. Silva et al. 155; R • Alto Paraíso de Goiás; 15 Mar. 2020; fl.; L. Echternacht et al. 2840; OUPR • Nova Roma; 21 Feb. 2018; M.L.O. Trovó et al. 753; CEN, OUPR, RB. Description Perennial herbs, usually solitary, with an erect and self-supporting habit, 24.4–70.7 cm tall; rhizome present, usually conspicuous, aerial stem 4.1–30.5 cm long, sparsely pubescent, usually branched or solitary, internode 1–6 mm. Leaves persistent, arranged along the stem, chartaceous, flexible, elliptical or elliptical-lanceolate, light green to brownish when old, recurved, amplexicaul, 0.83–2.3 × 0.09– 0.51 cm, pubescent, margins straight and hirsute at the base and pubescent distally, apex acuminate to rounded. Spathes ca 2 × as long as the leaves, glabrous, apex glabrous and rounded. Scapes 1−10 per branch, arranged in a terminal umbelliform inflorescence or solitary, 18.3–46.2 cm long, glabrous. Capitula discoid, white-villous, 4–9 mm in diam.; involucral bracts in 3−5 series, oblong or oblong-ovate, castaneous, concave-convex, ca 2 mm long, glabrous, margin ciliate, apex rounded; receptacle hemispherical, pilose. Flowers dimerous; floral bracts linear, castaneous, concave-convex, ca 1.5 mm long, pilose distally, margin ciliate, apex obtuse or rounded. Staminate flowers 2–2.5 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 toward the obtuse apex; anthophore fleshy, elongate; corolla fused into a tube, hyaline, membranaceous, ca 1.5 mm long, glabrous; stamens 2–2.5 mm; anthers 2, exerted, ca 0.5 mm long. Pistillate flowers ca 2 mm long, sessile or with pedicel 0.3 mm long; sepals 2, fused at the base, oblong, castaneous-hyaline, ca 2 mm long, pilose distally, margin ciliate to glabrescent toward the obtuse or rounded apex; petals 2, free, oblong, hyaline, ca 1.5 mm long, pilose distally on the abaxial surface, margin ciliate toward the obtuse or rounded apex; gynoecium 1.5 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 rollimae sp. nov. is restricted to the state of Goiás (Fig. 3). It has been recorded in the Chapada dos Veadeiros National Park and adjacent remnants of native vegetation. The species is also found within the Chapada de Nova Roma Ecological Station, a conservation unit now enclosed within the Chapada dos Veadeiros National Park. It typically inhabits rocky fields, over sandy and often waterlogged soils in areas with full sunlight exposure. Flowering specimens have been recorded in the following months of the year: February, March, April, May, July, September, and November. Preliminary conservation assessment The species is recorded in the protected areas of the Chapada de Nova Roma Ecological Station and the Chapada dos Veadeiros National Park. With an AOO of 8000 km 2, the species is classified as Critically Endangered: CR B2ab(iii). Its distribution is restricted and severely fragmented, with populations composed of few mature individuals. Although it occurs in protected areas, the species is endemic to the Cerrado, a domain under significant pressure from recurrent fires and the conversion of native vegetation into monocultures and pastures. Taxonomic remarks The specimens of Paepalanthus rollimae sp. nov. were previously identified as P. trichophyllus, as the two species share traits such as elongated stem, leaves arranged along the stem, castaneous involucral bracts, and dimerous flowers. A comparative analysis revealed additional distinguishing features. When compared to populations from the type locality of P. trichophyllus in São João del-Rei, P. rollimae differs in having leaves with straight margin (vs involute), glabrous spathe (vs pilose) with rounded apex (vs acute or lacerate), glabrous scape (vs densely pilose), oblong or oblong-ovate involucral bracts (vs obovate or wide-elliptic), 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 mm long (vs 3 mm long) with sepals ca 2 mm long (vs 3 mm long) and oblong, hyaline petals ca 1.5 mm long (vs elliptic, cream-colored to golden, 2.5 mm long), gynoecium ca 1.5 mm long (vs 3 mm long), and stigmatic branches slightly longer than the nectariferous branches (vs ca 1 mm longer than the nectariferous branches). In comparison to the morphotype of Paepalanthus trichophyllus found in Itutinga, P. rollimae sp. nov. has differences such as leaves with straight margin (vs involute), glabrous spathe (vs pilose) with rounded apex (vs acute or lacerate), glabrous scape (vs densely pilose), oblong or oblong-ovate involucral bracts (vs obovate), sepals and petals of staminate flowers ca 1.5 mm long (vs 1.8 mm long), and oblong petals of pistillate flowers (vs obovate). In contrast to the morphotype of P. trichophyllus found in Serra da Canastra National Park, P. rollimae can be distinguished by its plants being 24.4–70.7 cm tall (vs 10.35–20.1 cm tall), stem 4.1–30.5 cm long (vs 0.8–2 cm long), leaves recurved, amplexicaul (vs patent, sessile, when the stem is short) with straight margin (vs involute when the stem is elongated and not restricted to rosette), apex of the spathe rounded (vs acute), scape 18.3–46.2 cm long (vs 9.1–17.5 cm long), oblong or oblong-ovate involucral bracts (vs obovate), oblong petals of pistillate flowers (vs elliptic), and stigmatic branches slightly longer than the nectariferous branches (vs ca 0.5 mm longer than the nectariferous branches). The species also resembles the geographically close Paepalanthus atratus (Moldenke) L.E.F.Silva & Trovó but differs ecologically and morphologically. While P. rollimae sp. nov. inhabits grasslands with full sunlight exposure, P. atratus is found in the shade of gallery forests. Morphologically, P. rollimae can be distinguished by its sparsely pubescent stem (vs glabrous); elliptical or elliptical-lanceolate, pubescent leaves (vs lanceolate, glabrous) with margin hirsute at the base and pubescent distally (vs glabrous) and rounded or acuminate apex (vs acute), spathe with rounded apex (vs acuminate or acute), staminate flowers 2–2.5 mm long (vs 1.1 mm long) with obovate sepals (vs obovate-oblong), petals ca 1.5 mm long (vs ca 0.5 mm long), and pistillate flowers ca 2 mm long (vs 1.5 mm long) with oblong sepals ca 2 mm long, pilose distally (vs obovate-oblong, 1.5 mm long, glabrous) and oblong petals (vs elliptic to obovate). Paepalanthus rollimae sp. nov. can be distinguished from P. flaccidus, another morphologically similar and sympatric species, by its sparsely pubescent stem (vs glabrous). elliptical or elliptical-lanceolate, pubescent leaves (vs linear or linear-acicular, glabrous) with straight margin hirsute at the base and pubescent distally (vs involute, hirsute at base and glabrous distally) with acuminate or rounded apex (vs acute), spathe with rounded apex (vs acute), discoid, white-villous capitula (vs hemispherical, white to cream-colored), oblong or oblong-ovate, castaneous involucral bracts (vs elliptic, obovate or ovate, hyaline to golden), staminate flowers 2–2.5 mm long (vs 1.5 mm long), and pistillate flowers ca 2 mm long (vs 1.5 mm long) with oblong sepals