taxonID	type	description	language	source
9E06820BFF90FFF5FDE14099FD15DD17.taxon	description	Figs 1, 5	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF90FFF5FDE14099FD15DD17.taxon	materials_examined	– Type: BRAZIL – “ Provinciae Bahiensis ” [Bahia] • habitat in sylvis Catingas dictis ad flumen St. Francisci; s. d. [Oct. 1818]; C. F. P. von Martius s. n.; lectotype: M [M- 0172333], designated by Lourteig (1994: 150). Other material examined BRAZIL – Bahia • Blanchet 5256; P [photo] • Almadina, Faz. Beija-Flor, Serra da Pancadinha; 11 Aug. 1972; Pinheiro 1902; P [photo] • same data as for preceding; Pinheiro 1904; CEPEC, P [photo] • Almadina; 18 Jul. 1978; Mori et al. 10261; CEPEC • Almadina, Faz. Beija-Flor, ca 3 km al Sul de Almadina; 19 Jul. 1978; Mori et al. 10298; CEPEC, P [photo] • Ibicaraí, Itapé, lado sul; 3 Mar. 1971; Pinheiro 1035; P [photo] • same data as for preceding; Pinheiro 1041; P [photo] • Ibicaraí, Rod. BR- 415, a 2 km W de Ibicaraí; 17 Mar. 1979; Mori et al. 11602; CEPEC, P [photo] • Ilhéus, Área do CEPEC; 2 Oct. 1979; Mori 12486; CEPEC, P [photo] • same data as for preceding; 14 Oct. 1981; Hage & Brito 1471; CEPEC, P [photo] • Itabuna; 16 Dec. 1966; Emygdio et al. 2423; R • Mucuri, Fazenda Afonsópolis; 7 Aug. 1965; Lanna Sobrinho 1130; P [photo] • Mucuri, “ próx. à ponte sobre o Rio Mucuri ” [close to bridge above Mucuri River]; 15 Sep. 1978; Mori et al. 10535; CEPEC, P [photo] • Porto Seguro, junto à fonte; 30 May 1962; Duarte 6721; P [photo] • Porto Seguro; 19 Oct. 1969; Jesus 477; CEPEC • Porto Seguro; 28 Nov. 1970; Emygdio & Emmerich 3012; P [photo] • Porto Seguro; 21 Mar. 1974; Harley 17217 a; CEPEC, P [photo], RB • 9 Oct. 1969; Jesus 478; CEPEC • Porto Seguro, Km 16 de Porto Seguro-Eunápolis; 17 Jul. 1981; Brito & da Vinha 41; CEPEC • Porto Seguro; 13 Oct. 2006; Amorim et al. 6447; CEPEC, HUEFS • Prado, “ Parque Nacional do Descobrimento ” [Descobrimento National Park]; 17 ° 11 ′ S, 39 ° 20 ′ W; 3 Nov. 2009; Matos et al. 1916; CEPEC • Santa Cruz Cabrália; 21 Mar. 1978; Mori et al. 9767; CEPEC • Santa Cruz Cabrália; 18 Oct. 1978; Mori et al. 10817; CEPEC, P [photo] • Santa Cruz Cabrália, “ Estação Ecológica do Pau-Brasil ” [Pau-Brasil Ecological Station]; 3 Nov. 1978; Euponino 350; P [photo] • Santa Cruz Cabrália, “ Estação Ecológica do Pau-Brasil ” [Pau-Brasil Ecological Station]; 4 Mar. 1983; Brito & da Vinha 184; CEPEC • Santa Cruz Cabrália; 21 Nov. 1984; Santos 456; CEPEC.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF90FFF5FDE14099FD15DD17.taxon	discussion	Typification remarks Zuccarini (1825) described O. polymorpha based on a material collected by von Martius while the Bavarian naturalist was traveling in the São Francisco River, presumably in the surrounding of Malhada or Carinhanha, in the state of Bahia, in October of 1818. This specimen was mounted in M (Fig. 1) and faithfully represented in the tab. III of Zuccarini (1825). While describing O. polymorpha, Zuccarini (1825) proposed several varieties (a to f; Table 1), which, in his opinion, represented a morphological range of several other interconnected forms (“ polymorphae hujus specie varietates, plurimis allis formis inter se conuexae ”). The first of these varieties (“ var. a) staphyleoides ”) was characterized as presenting “ leaflets always subrhombic, acuminate, pubescent, and peduncles with simple or bifid divisions ” (i. e., the dichasial branches). As interpreted by Lourteig (1994), this variety and the name that it received at species level, O. staphyleoides (Zucc.) Progel, were typified by the same specimen used to typify the species, i. e., the sample gathered by von Martius in the state of Bahia. Another specimen also collected by Martius in a nearby location, but presumably on the other side of the São Francisco River, in the state of Minas Gerais, and housed at G (G 00383166) (Fig. 4), was listed by Lourteig (1994) as an isotype of O. polymorpha. Despite the overall similarity of these two specimens (Figs 1, 4), we prefer not to treat this material as belonging to the same gathering, not only because it was collected on the other side of the river São Francisco, but also because it differs from the type by the more congested leaves in the stem distal end, the less pronounced indumentum on the distal end of stem, and the less pronounced leaf venation on the abaxial side of the leaflet blades (Fig. 4). General remarks Other than the type, which was likely collected in semideciduous forests along the São Francisco River, we are not convinced that other specimens can be unambiguously assigned to O. polymorpha; however, to help in the application of this name, we list above several specimens collected in the southern Bahia coastal rainforests (Fig. 5) that could also belong to this taxon in the narrower circumscription adopted here. Oxalis polymorpha includes plants with the young stem with abundant to very abundant, curved or patent hairs, leaves either congested and almost forming one or more pseudo-whorls or more or less equally distributed along the stem, leaflet blades with moderate to abundant, appressed hairs, glabrescent in the adaxial surface, more densely arranged abaxially, apex usually acute to acuminate, lateral leaflets with a slightly to strongly asymmetric base, inflorescences with the dichasial branches usually elongated, having the flowers distally congested or, less commonly, distributed along the branches, pedicels lacking glandular hairs, corollas ranging from white to slightly pinkish (or even yellow, following the label from Martius s. n., M- 0172333), and capsules with short apical prolongations, up to ca 0.5 mm long (see Table 3 for a comparison with species segregated here). Fiaschi (2014) adopted a very wide circumscription for O. polymorpha, as noted from the leaf morphological variation that was illustrated in his fig. 7 G – H. Based on the updated circumscription presented here, the first four specimens of this illustration belong to O. decipiens, Amorim 5549 (CEPEC) belong to a yet undescribed taxon, and the remaining specimens belong to O. polymorpha s. str. According to this same author, O. polymorpha is very similar to O. puberula Nees & Mart., and hardly distinguishable by the acute to acuminate (vs usually obtuse to rounded) leaflet apex. Moreover, despite O. polymorpha appears to differ consistently from O. neuwiedii by the pedicels lacking glandular hairs (Lourteig 1994; Fiaschi 2014), the distinction between these two species is sometimes confusing, and should be investigated with a more comprehensive sampling using morphometric and molecular data. To adopt the narrower circumscription of O. polymorpha presented here, several taxa formerly placed as synonymous, treated at infraspecific level, or representing new species whose specimens were previously listed under this taxon are described below.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF9BFFF6FDF543EBFB20DCB3.taxon	description	urn: lsid: ipni. org: names: 77360846 - 1 Figs 5 – 6	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF9BFFF6FDF543EBFB20DCB3.taxon	diagnosis	Diagnosis This new species differs from all other species of O. sect. Polymorphae by the presence of leaflets clearly three-nerved, suprabasal actinodromous (terminal blade) or basal actinodromous (lateral blades), characterized by having one basal pair of secondary veins almost as thick as the midrib, extending up to ca ⅔ of the blade length.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF9BFFF6FDF543EBFB20DCB3.taxon	etymology	Etymology The name of this species honors the Brazilian botanist and Malpighiaceae expert André M. Amorim, who dedicated a large part of his career to improving our knowledge of the southern Bahia forests. He was the collector of the type of this new species and has devoted himself to cultivate one of the specimens used for the photographic plate presented in Fig. 6.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF9BFFF6FDF543EBFB20DCB3.taxon	materials_examined	Type material BRAZIL – Bahia • Itanhém, Estrada Itanhém a Batinga, ca 16 km. “ Ramal à direita, dando acesso a Faz. Pedra Grande, de Prop. de Etevaldo Rezende da Silva ” [right branch, access to Faz. Pedra Grande, owned by Etevaldo Rezende da Silva]; 17 ° 08 ′ 17 ″ S, 40 ° 25 ′ 34 ″ W; 29 Dec. 2004; fl; A. M. Amorim et al. 4614; holotype: CEPEC. Other material examined BRAZIL – Bahia • Itanhém, “ ca 16 km da estrada que ruma a oeste de Itanhém, Antiga Fazenda Pedra Grande (Mata do Otevaldo) ” [ca 16 km from the road heading west from Itanhém, Former Fazenda Pedra Grande (Otevaldo's Forest)]; 17 ° 07 ′ 58 ″ S, 40 ° 25 ′ 18 ″ W; 27 Aug. 2022; st.; P. Fiaschi et al. 5457; FLOR.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF9BFFF6FDF543EBFB20DCB3.taxon	description	Description Unbranched or few-branched, erect subshrubs 20 – 40 cm tall; young stem with moderate, short, curved hairs, glabrescent towards the base; older stem brownish, terete, slightly striate longitudinally. Leaves pinnate-trifoliolate, distributed along the stem, mostly grouped at stem apex, but not forming a pseudo-whorl, the internodes 1 – 15 mm long; the petioles 35 – 80 × 0.4 – 0.8 mm, canaliculate adaxially, with moderate to abundant, curved to straight hairs, usually verruculose near the base, the base pulvinate, enlarged to ca 1.5 mm diam.; the rachis 9 – 20 mm long, similar to the petiole; petiolules ca 1 mm long, with abundant, appressed hairs; leaflet blades adaxially glabrescent, with occasional to sparse appressed hairs, especially along the midrib and along the margin; abaxially with abundant, appressed hairs, mostly along the midrib; membranous to chartaceous, adaxially green, abaxially green to slightly purplish. Venation: midrib impressed to canaliculate adaxially, prominent abaxially; clearly three-nerved, suprabasal actinodromous (terminal blade) or basal actinodromous (lateral blades), having one basal pair of secondary veins slightly thinner than the midrib (ca 1 mm vs ca 1.5 mm wide), decurrent, extending up to ca ⅔ of blade length, 3 – 4 distal secondary pairs thinner than the basal one, and one basal-most intramarginal secondary pair reaching up to ca ½ of the blade length; secondary veins slightly raised abaxially; intercostal tertiary vein fabric visible, irregular-reticulate, exterior tertiary course looped, quaternary vein fabric irregular-reticulate, areolation of good development, freely ending veinlets mostly one-branched. Terminal blade 50 – 74 × 22 – 31 mm, ovate to lanceolate or slightly rhombic, the apex acuminate to caudate, the base cuneate to attenuate. Lateral leaflets opposite, the blades 40 – 49 × 15 – 21 mm, ovate to lanceolate, the apex acuminate, the base subsymmetrical to asymmetrical, cuneate to obtuse, sometimes attenuate. Dichasial cymes axillary, shorter than the leaves; the peduncle 42 – 62 mm long, flattened to adaxially canaliculate, with moderate, short, patent or curved hairs; dichasial branches 2, up to ca 10 mm long, each with the flowers (or scars) densely grouped along the entire length; bracts 1 – 1.5 mm long, narrowly triangular, abaxially with abundant, appressed hairs; bracteoles up to ca 1 mm long, narrowly triangular, with abundant, appressed hairs. Flower buds ca 7 × 2.5 mm, lanceolate, acuminate. Pedicel 3 – 7 mm long, articulated at base, leaving a persistent foot up to ca 0.5 mm long; with moderate, ascending to curved hairs. Sepals light green, 5.5 – 7.5 × 1 – 1.8 mm, lanceolate, the exposed part with moderate, ascending to appressed hairs, the apex acuminate. Corolla yellow, ca 13.5 mm diam., petals 11.5 – 13 mm long, each with two orange maculae above the throat; short-styled morph: filaments connate for ca 0.5 mm of their length; shorter filaments ca 1.5 mm long, glabrous, each with a basal knob, longer filaments ca 4 mm long, non-appendiculate, distally hispidule; pistil: ovary ca 0.5 mm long; styles ca 0.5 mm long, recurved, hispidule; stigmas oblate, facing outwards; gynophore inconspicuous, ca 0.2 mm long; long-styled morph: filaments connate for ca 1 mm of their length; shorter filaments ca 1.5 mm long, glabrous, longer filaments ca 4 mm long, non-appendiculate, distally with occasional, short hairs; pistil: ovary ca 1 mm long; styles ca 4 mm long, erect, hispidule for the entire length; stigmas oblate; carpels uniovulate. Capsules unknown.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF9BFFF6FDF543EBFB20DCB3.taxon	conservation	Preliminary conservation status assessment This species is so far known from a single patch of semideciduous forest in a private farmland situated in a very fragmented landscape at the border between the states of Bahia and Minas Gerais, where there are few remaining sites of forested areas. In a recent visit to this area, in August of 2022, we were able to locate less than 20 individuals of the species growing in ʻcabrucaʼ, a system of cocoa cultivation under the canopy of native trees that was traditionally employed in the region, and which is known to provide shelter for the local biodiversity (Sambuichi & Haridasan 2007; Scroth et al. 2011). Since this species occurs in a single location (area of occupancy of 4 km ²), in an extremely fragmented landscape that suffered from both extent and quality loss, we recommend it to be assessed as Critically Endangered following the IUCN criteria CR B 2 ab (iii) (IUCN 2012).	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF9BFFF6FDF543EBFB20DCB3.taxon	discussion	Remarks This species can be easily distinguished from the remaining species of O. sect. Polymorphae by the presence of three-nerved leaflets, which are unique to this species in the section. From other similar, yellow-flowered species of O. sect. Polymorphae, whose leaves are not congested in a terminal pseudo-whorl, it can also be distinguished from O. decipiens by the leaf terminal blades 50 – 74 mm long (vs 46 – 122 mm long), unbranched (vs usually bifid at base) dichasial branches, and flowers with the pedicel 3 – 7 mm long (vs 1.5 – 2 mm long), and from O. animarum sp. nov. by the leaf blades abaxial surface with abundant, appressed hairs (vs with moderate, patent to appressed hairs, mixed with shorter and thicker, darker hairs), the peduncles 42 – 62 mm long (vs 11 – 30 mm long), and the pedicels with moderate, ascending to curved hairs (vs with abundant, short, patent hairs, mixed with sparse to moderate, longer, glandular hairs).	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF9BFFF6FDF543EBFB20DCB3.taxon	distribution	Distribution and ecology This species is only known from a small semideciduous forest fragment located in the municipality of Itanhém, close to the border between the states of Bahia and Minas Gerais (Fig. 5).	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF98FFEBFDFC434DFEF5DBC9.taxon	description	urn: lsid: ipni. org: names: 77360847 - 1 Figs 5, 7	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF98FFEBFDFC434DFEF5DBC9.taxon	diagnosis	Diagnosis This new species differs from O. decipiens by the leaf blades with 4 – 7 (vs 7 – 12) pairs of secondary veins, abaxially with moderate, patent to appressed hairs, mixed with shorter and thicker, darker hairs (vs with abundant, appressed hairs), inflorescences with unbranched (vs usually bifid at base) dichasial branches, flowers with the pedicel 3 – 4.5 mm long (vs 1.5 – 2 mm long), bearing patent hairs, mixed with sparse to moderate, longer, glandular hairs (vs with appressed or curved hairs), and fruits shorter (vs longer) than the calyx lobes, with the carpels prolonged for ca 1 mm of their length (vs carpels prolonged for ca 2 mm of their length).	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF98FFEBFDFC434DFEF5DBC9.taxon	etymology	Etymology The specific epithet ʻ animarum ʼ (latin: from the souls) refers to the city of Cruz das Almas. The word in Portuguese for ʻsoulʼ is ʻalmaʼ.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF98FFEBFDFC434DFEF5DBC9.taxon	materials_examined	Type material BRAZIL – Bahia • Cruz das Almas, Mata da Cazuzinha; 4 Nov. 2011; fl, fr; G. Costa & S. F. Conceição 580; holotype: HURB; isotype: HUEFS. Other material examined	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF98FFEBFDFC434DFEF5DBC9.taxon	description	Description Unbranched or few-branched, erect subshrubs, 30 – 100 cm tall; young stem with abundant to very abundant, short, curved hairs, more densely so at the distal end; older stem dark-brown, terete, slightly striate longitudinally. Leaves pinnate-trifoliolate, equally distributed along the stem, the internodes 10 – 24 mm long; the petioles 35 – 65 mm long, 0.5 – 0.7 mm diam., canaliculate adaxially, with abundant to very abundant, short, patent to curved hairs, curved along the channel, the base pulvinate, enlarged to ca 1.2 mm diam.; the rachis 8 – 20 mm long, similar to the petiole; petiolules ca 1 mm long, with abundant, appressed hairs; leaflet blades adaxially glabrescent, with short, curved hairs along the midrib and the margin, abaxially with moderate, patent to appressed hairs, mostly along the midrib, mixed with shorter and thicker, darker (yellow to brownish), mostly appressed hairs; membranous to chartaceous, adaxially dark green, abaxially lighter green. Venation: midrib impressed adaxially, prominent abaxially; secondary veins 4 – 7 pairs, inconspicuous, impressed on both surfaces, sometimes slightly raised abaxially; intercostal tertiary veins sometimes visible, irregular-reticulate, exterior tertiary course looped, quaternary veins fabric irregular-reticulate, areolation moderately developed, inconspicuous, free ending veinlets not seen. Terminal blade 32 – 80 × 16 – 27 mm, ovate to lanceolate, the apex acuminate to caudate, the base cuneate to attenuate. Lateral leaflets opposite, the blades 22 – 54 × 13 – 28 mm, ovate, the apex acuminate to caudate, the base subsymmetrical to asymmetrical, obtuse or cuneate to attenuate. Dichasial cymes axillary, much shorter than the leaves; the peduncle 11 – 30 mm long, slightly flattened laterally, with moderate to abundant, short, patent or curved hairs; dichasial branches 2, 1.5 – 4 mm long, each with the flowers (or scars) densely grouped along the entire length; bracts 0.5 – 1 mm long, triangular, abaxially with moderate to abundant, appressed hairs; bracteoles ca 0.5 mm long, triangular, with sparse to moderate, appressed hairs. Flower buds 4 – 4.5 × ca 2 mm, ovoid to ellipsoid, acute to acuminate. Pedicel 3 – 4.5 mm long, articulated at base, leaving a persistent foot up to ca 1 mm long; with abundant, short, patent hairs, mixed with sparse to moderate, longer, glandular hairs. Sepals greenish, ca 5 × 1.3 – 1.7 mm, lanceolate, the apex acuminate, the exposed part with moderate to abundant, short, patent hairs intermixed with longer glandular hairs. Corolla yellow, ca 10 mm diam., petals ca 8 mm long, each with two orange maculae above the throat; mid-styled morph: filaments connate for ca 0.7 mm of their length; shorter filaments ca 1.5 mm long, glabrous; longer filaments ca 4.5 mm long, appendiculate at ca 2 mm of their length, distally hispidule; pistil: ovary ca 1.2 mm long; styles ca 2 mm long, erect, hispidule for the entire length; stigmas oblate; gynophore ca 0.7 mm long. Capsules ca 4.5 × 4.5 mm, pyriform, with moderate, glandular and patent intermixed hairs, slightly shorter than the calyx lobes, the apex prolonged for ca 1 mm of their length; locules one-seeded, internally glabrous; seeds ca 2 × 1.5 mm, semi-obloid, with a honeycombed-foveolate surface.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF98FFEBFDFC434DFEF5DBC9.taxon	conservation	Preliminary conservation status assessment This species is only known from the Parque Florestal Mata de Cazuzinha, a small patch of semideciduous forest protected in the urban area of the municipality of Cruz das Almas, in the Recôncavo Baiano region, which is heavily fragmented due to large, cultivated areas of tobacco, sugarcane, cassava, tropical fruits, and cattle farming. Despite ʻMata de Cazuzinhaʼ being a protected area, the region where it is situated suffered from both extent and quality loss. The area of occupancy of the species is 4 km ². We therefore recommend that it should be considered as Critically Endangered following the IUCN criteria CR B 2 ab (iii) (IUCN 2012).	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF98FFEBFDFC434DFEF5DBC9.taxon	discussion	Remarks Fiaschi (2014) listed one specimen of O. animarum sp. nov. (H. P Bautista 1323, RB) under his wide circumscription of O. polymorpha. Among the main diagnostic features of this new species are the leaves distributed along the stem, the inflorescences with the peduncle much shorter than the petiole of the corresponding leaf, the flowers with glandular hairs on the pedicel and sepals, the leaf blades abaxially with patent to appressed hairs, mixed with shorter and thicker, darker (yellow to brownish) hairs, and the pyriform fruits shorter than the calyx lobes, with the carpels prolonged for ca 1 mm of their length.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF98FFEBFDFC434DFEF5DBC9.taxon	distribution	Distribution and ecology This new species is endemic to seasonally dry forests in the surroundings of Cruz das Almas (Fig. 4). It is only known from the ʻMata de Cazuzinhaʼ, a small urban remnant of the forests that once occurred in the region.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF85FFEEFD2045ABFEB8DAB4.taxon	description	Figs 5, 8	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF85FFEEFD2045ABFEB8DAB4.taxon	materials_examined	Type: BRAZIL – “ Rio de Janeiro ” [Minas Gerais] • “ [Vila] Casal, près dʼUba (Ubá), sur la ligne du chemin de fer de D. Pedro 2 °, avec Mr. Albuquerque ” [Village Casal, near Ubá, along the railway line of Dom Pedro 2 °, with Mr. Albuquerque]; 26 Feb. 1875; A. F. M. Glaziou 7561; lectotype: C [C 10016336], designated by Lourteig (1994: 150); isolectotypes: P [P 02440302], S [S-R- 8335].	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF85FFEEFD2045ABFEB8DAB4.taxon	materials_examined	Type: BRAZIL – “ Rio de Janeiro ” [Espírito Santo] • zwichen Villa Nova [now Nova Almeida] und Praya Molle; M. Neuwied s. n.; Apr. 1816 [presumably Dec. 1815, see Nomenclatural remarks]; lectotype: M [M- 0121064, pro parte], designated by Lourteig (1994: 150) — only the left and central branches (see Fig. 9 A); isolectotype: FI [FI 005091]. Other material examined BRAZIL – Espírito Santo • Colatina, Fazenda São Gabriel; 24 Mar. 1978; fl; A. Lourteig 3217; CEPEC, P [photo] • Colatina, Fazenda São Gabriel; ca 120 m a. s. l.; 24 Mar. 1978; fl; A. Lourteig 3219; P [photo] • Colatina, Santa Rosa da Graça Aranha; ca 120 m a. s. l.; 24 Mar. 1978; fl; A. Lourteig 3221; CEPEC, P [photo] • Governador Lindemberg, Pedra de Santa Luzia, prop. Firmino Sottele; 19 ° 16 ′ 54 ″ S, 40 ° 27 ′ 43 ″ W; 350 – 600 m a. s. l.; 26 Apr. 2007; fl, fr; V. Demuner et al. 3890; MBML, SPF • Governador Lindemberg, Morelo, propr. Fernando Nicolli; 19 ° 08 ′ 55 ″ S, 40 ° 27 ′ 28 ″ W; 13 Nov. 2006; V. Demuner et al. 3043; SPF • Linhares, Reserva Florestal de Linhares – Cia. Vale do Rio Doce, MME, talhão 89; 12 May 2000; fl; P. Fiaschi et al. 240; FLOR, SPF • Linhares, “ Reserva Florestal da Companhia Vale do Rio Doce (CVRD), área experimental do MME ” [Vale do Rio Doce Company Forest Reserve, experimental area of the MME], RFL 89; 19 ° 07 ′ 57 ″ S, 40 ° 04 ′ 58 ″ W; 75 m a. s. l.; 1 Feb. 2002; fl; P. Fiaschi et al. 964; FLOR, RB, SPF • Linhares,; “ Reserva da Vale, nas proximidades do escritório ” [Vale Reserve, near the office]; 19 Jan. 2011; fl; P. Fiaschi et al. 3469; FLOR, SPF • Linhares, “ Reserva Natural Vale, proximidades do escritório ” [Vale Natural Reserve, near the office]; 19 ° 00 ′ 03 ″ S, 40 ° 41 ′ 16 ″ W; 5 Feb. 2016; fl; P. Fiaschi & J. L. Costa Lima 4656; FLOR • Linhares, Reserva Natural Vale, Estrada Aceiro; 3 Apr. 1993; fl; G. L. Farias 605; CVRD, FLOR, SPF • Linhares, Reserva Natural Vale, Estrada Municipal do MME, RFL- 089 / 86; 4 Mar. 2008; fl, fr; D. A. Folli 5877; CVRD, FLOR, SPF • Linhares, Reserva Natural Vale, Estrada Peroba Amarela; 12 Mar. 1987; fl; D. A. Folli 629; CVRD, FLOR, SPF • Linhares, Reserva Natural Vale do Rio Doce (particular); 30 m a. s. l.; 26 Sep. 1978; fl; A. M. Carvalho et al. 83; FLOR, RB • Linhares, Reserva Florestal Vale do Rio Doce; 14 Oct. 1992; fl, fr; G. Hatschbach et al. 58067; MBM • Linhares, Reserva Natural da Vale, Trilha do Flamengo; 19 ° 09 ′ 47.8 ″ S, 39 ° 58 ′ 58 ″ W; ca 50 m a. s. l.; 12 May 2012; fl; J. A. Lombardi et al. 9643; CVRD [photo] • Linhares, Reserva Natural Vale do Rio Doce, Estrada da bomba dʼágua; 21 Apr. 1983; A. L. Peixoto & H. C. de Lima 1778; RB, SPF • Linhares, Reserva Natural da Vale, Estrada Guaribu Amarelo; 24.26936 ° S, 49.26981 ° W; 14 Apr. 2011; J. C. Lopes et al. 161; ESA, SPF • Linhares, Ponta de Ouro, “ margens da Rodovia ES- 358 ” [margins of Highway ES- 358]; 19 ° 12 ′ 29.9 ″ S, 40 ° 10 ′ 01.7 ″ W; 80 m a. s. l.; 16 Nov. 2012; fl; A. M. Assis & J. Freitas 3350; MBML • Rio Bananal, “ Estrada pavimentada para Novo Brasil ” [Paved road to Novo Brasil]; 19 ° 09 ′ 05.9 ″ S, 40 ° 20 ′ 51.6 ″ W; 26 Jan. 2009; C. P. Bruniera et al. 145; SPF • Sooretama, Reserva Biológica de Sooretama, estrada Cupido; 19 ° 03 ′ 42 ″ S, 40 ° 08 ′ 18 ″ W; 30 m a. s. l.; 20 Feb. 2021; fl; C. A. P. Toledo & H. Medeiros 578; FLOR, RB • Sooretama, Reserva Natural da Vale (RNV); 19 ° 09 ′ 03.4 ″ S, 40 ° 04 ′ 15.1 ″ W; 59 m a. s. l.; 3 Feb. 2013; fl, fr; M. G. Caxambu et al. 4564; HCF [photo] • Sooretama, Reserva Natural da Companhia Vale do Rio Doce, MME; 19 ° 08 ′ 03.2 ″ S, 40 ° 05 ′ 02.2 ″ W; 74 m a. s. l.; 30 Apr. 2008; M. M. M. Lopes et al. 1592; SPF • Sooretama, “ Reserva Biológica de Sooretama, entrada da picada em frente ao antigo posto de vigia ” [Sooretama Biological Reserve, track entrance in front of old watch post]; 24 Aug. 2012; fl, fr; T. B. Flores & G. O. Romão 1119; MBML [photo], RB • Sooretama, Sooretama, Parque do Zooretama; 26 May 1965; fl; A. J. Andrade & M. Emmerich 1981; P • Sooretama, “ Sooretama, do lado Norte da sede da Reserva de Sooretama ” [Sooretama, on the north side of the Sooretama Reserve headquarters]; 11 Jul. 1969; D. Sucre 5449; RB • Serra, “ a 1 – 3 km de Nova Almeida, em direção a Santa Cruz ” [1 – 3 km from Nova Almeida, going to Santa Cruz]; 19 Jul. 1973; D. Araujo & A. L. Peixoto 309; RB, SPF. – Minas Gerais • Coronel Pacheco, Fazenda da Companhia; 2 Jun. 1945; fl; E. P. Heringer 1921; SP, SPF • Coronel Pacheco, Fazenda da Liberdade; 20 Feb. 1942; E. P. Heringer 946; SPF • Marliéria, “ 2 km após a entrada do Parque Estadual do Rio Doce, em direção à ponte Queimada e aos experimentos da Teresa Spósito (GEF) ” [2 km beyond the Rio Doce State Park entrance, in direction to Queimada bridge and Teresa Spósitoʼs experiments]; 19 ° 42 ′ 12 ″ S, 43 ° 30 ′ 52 ″ W; 29 Nov. 2000; fl; A. A. Santos et al. 866; CEN, FLOR • Marliéria, Pq. Estadual do Rio Doce, Mumbaça; 26 Mar. 2006; J. Ordones et al. s. n.; SPF 176576 • Marliéria, Parque Rio Doce, Trilha da Campolina; 19 ° 41 ′ 55 ″ S, 42 ° 30 ′ 23 ″ W; 24 Jan. 2018; fl; E. Richetti et al. 64; FLOR • Marliéria, Parque Florestal do Rio Doce; 15 Feb. 1973; L. E. Mello-Filho et al. 3755; R. – Rio de Janeiro • Cantagalo; s. d.; Peckolt s. n.; BR • Barra Mansa, ARIE Floresta da Cicuta; 22 ° 32 ′ 54 ″ S, 44 ° 05 ′ 18 ″ W; 2 Mar. 2024; J. C. Vasques et al. 57; FLOR, HUEFS, RB, SPF • Volta Redonda, Floresta da Cicuta; 12 Oct. 1985; J. P. P. Carauta et al. 5095; RB; • Volta Redonda; 21 Feb. 1987; R. B. Pineschi 40; RB • Volta Redonda; 21 Feb. 1987; R. B. Pineschi 41; RB; • Volta Redonda; 2 Jan. 1992; M. R. Ascenção et al. 18; RB.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF85FFEEFD2045ABFEB8DAB4.taxon	description	Description Unbranched, erect subshrubs, 15 – 60 cm tall; young stem with abundant to very abundant, curved hairs, more densely so at the distal end; older stem beige-cinereous to brownish, terete, slightly striate longitudinally. Leaves pinnate-trifoliolate, distributed along the stem, mostly grouped at stem apex, but not forming a pseudo-whorl, the internodes 3 – 22 mm long; the petioles 36 – 65 × 0.7 – 1.2 mm, canaliculate adaxially, with moderate to abundant, patent to curved hairs, curved along the channel, the base pulvinate, enlarged to ca 2 mm diam.; the rachis 8 – 20 mm long, similar to the petiole, sometimes slightly thinner, slightly enlarged distally; petiolules ca 1 mm long, with abundant, appressed to curved hairs; leaflet blades adaxially glabrous, ciliate along the margin, abaxially with abundant, appressed hairs; chartaceous, adaxially dark green, sometimes with a lighter shaded band along the midrib, abaxially lighter green, sometimes vinaceous. Venation: midrib canaliculate adaxially, raised abaxially; secondary veins 7 – 12 pairs, slightly visible or inconspicuous, impressed adaxially, slightly raised abaxially; intercostal tertiary veins sometimes visible, irregular-reticulate, exterior tertiary course looped, quaternary veins fabric irregular-reticulate, areolation moderately developed, inconspicuous, free ending veinlets not seen. Terminal blade 46 – 122 × 20 – 43 mm, ovate to lanceolate, the apex acuminate to slightly caudate, the base cuneate to obtuse. Lateral leaflets opposite, the blades 33 – 85 × 13 – 32 mm, ovate to lanceolate, the apex acuminate to slightly caudate, the base subsymmetrical to asymmetrical, obtuse to rounded. Dichasial cymes axillary and cauliflorous, except in young plants, which may lack cauliflorous inflorescences, shorter than the leaves; the peduncle 10 – 75 mm long, slightly flattened, with abundant, curved hairs; dichasial branches (1 –) 2 (– 3), usually bifid at the very base, and thus appearing as 4 (– 6), 1 – 7 mm long, each with the flowers (or scars) densely grouped along the entire length; bracts ca 1 mm long, triangular, abaxially with moderate to abundant, appressed hairs; bracteoles 0.5 – 0.7 mm long, triangular, with moderate to abundant, appressed hairs. Flower buds 4 – 4.5 × 1.4 – 2 mm, ovate-acuminate. Pedicel 1.5 – 3.5 mm long, articulated at base, leaving a persistent foot up to ca 0.5 mm long, with abundant, short, appressed or curved hairs. Sepals greenish, 5 – 5.5 × 1 – 2.2 mm, oblong to lanceolate, the exposed part with abundant, curved hairs, the apex acuminate to obtuse. Corolla yellow, ca 9 mm diam., petals 8.5 – 9.5 mm long, each with two orange maculae above the throat; short-styled morph: filaments connate for ca 0.5 mm of their length; shorter filaments ca 3 mm long, glabrous, each with a basal knob, longer filaments ca 4.5 mm long, non-appendiculate, hispidule; pistil: ovary ca 0.8 mm long; styles ca 1 mm long, recurved, with a few setae; stigmas oblate; gynophore inconspicuous, up to ca 0.5 mm long; long-styled morph: filaments connate for 0.5 – 0.7 mm of their length; shorter filaments ca 1.2 mm long, glabrous, each with a basal knob, longer filaments 2.8 – 3.8 mm long, non-appendiculate or very slightly appendiculate at ca 1.5 mm long, hispidule or almost glabrous; pistil: ovary ca 0.8 mm long; styles ca 4 mm long, erect, hispidule for the entire length; stigmas oblate; gynophore 0.3 – 0.5 mm long. Capsules ca 5.5 × 5.5 mm, pyriform, glabrous, slightly longer than the calyx lobes, the apex prolonged for ca 2 mm of its length; locules one-seeded, internally glabrous; seeds ca 2.5 × 1.2 mm, ovoid, with a honeycombed-foveolate surface.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF85FFEEFD2045ABFEB8DAB4.taxon	conservation	Preliminary conservation status assessment Despite its widespread distribution (Fig. 5), O. decipiens occurs in a very fragmented area of lowland to submontane Atlantic forests in the states of Rio de Janeiro, Espírito Santo and Minas Gerais. The main threats to this species are the historical forest conversion into agricultural land for cattle grazing and eucalyptus reforestation for cellulose production. The region where this species occurs suffered from both extent and quality loss, but it is protected in large lowland Atlantic Forest remnants, such as the Rio Doce State Park, in Minas Gerais state, and the Reserva Natural Vale and Sooretama National Park, both in the state of Espírito Santo. Oxalis decipiens has an EOO of 81 772 km 2 and an AOO of 60 km 2, which could be expanded if additional populations are found. For these reasons we recommend that O. decipiens should be considered as Least Concern (LC) following IUCN (2012).	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF85FFEEFD2045ABFEB8DAB4.taxon	discussion	Nomenclatural remarks Oxalis decipiens was described by Progel (1877) based on two syntypes: Glaziou 7561, from the surroundings of Ubá (Minas Gerais state) and Peckolt s. n. (BR 529076 (bc) (photo)!), from Cantagalo (Rio de Janeiro state). Lourteig (1994) chose the specimen Glaziou 7561 at C as the lectotype, as it bears an identification label handwritten by A. Progel. Two specimens collected by Prince Max. Neuwied during his journey to Brazil from 1815 and 1817 are available at M and labeled as types of O. polymorpha var. cauliflora. The first (M- 0121064) was collected “ zw [ischen] Villa N [ova] u [nd] Praya Molle ”, between localities that, according to Moraes (2009) were visited between 20 th and 21 st December 1815, and which correspond to the current town of Nova Almeida and Praia Mole, at Espírito Santo state. This specimen was inadvertently chosen as the lectotype of Oxalis polymorpha var. cauliflora by Lourteig (1994), but it is a ʻmixtum compositumʼ, where the central leaf-bearing branches and the left stem with a few cauliflorous inflorescences correspond to this taxon (Fig. 9 A), while the two pieces of stem on the right side likely belong to what we are describing here as O. idimae sp. nov. (Fig. 9 B). The second specimen (M- 053323, Fig. 9 C) appears to belong to the same gathering of these two pieces of stem that were mounted on the right side in M- 0121064. In support of this interpretation, the petioles, and peduncles from Fig. 9 B are clearly thinner than those of Fig. 9 A, and the single leaf blade of Fig. 9 B dried greenish as those of Fig. 9 C, contrasting to the brownish color of the leaves from Fig. 9 A. Moreover, while the branches in Fig. 9 A bear inflorescences with bifid dichasial branches, which are commonly observed in O. decipiens (Fig. 5 I), those from Fig. 9 C are not bifid, resembling what is observed in O. idimae (see Fig. 10 F). The locality where M- 053323 was collected is unknown, but it was very likely gathered during the part of Neuwiedʼs expedition when he visited the northern part of Rio de Janeiro state, between September and November of 1815 (Moraes 2009), the region where O. idimae is presumably endemic (Fig. 5). Taxonomic remarks Oxalis decipiens can be distinguished from O. polymorpha by the usually cauliflorous (vs only axillary) inflorescences with bifid dichasial branches (appearing 4 (– 6) branched) (vs with single, unbranched dichasial branches), and by the pyriform capsules with the carpels apically prolonged for ca 2 mm long (vs carpels prolonged up to ca 0.5 mm long).	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF85FFEEFD2045ABFEB8DAB4.taxon	distribution	Distribution and ecology This species mostly occurs in the Rio Doce valley rainforests in the northern part of the state of Espírito Santo and in the eastern part of Minas Gerais, especially in the large forest fragment protected in the Parque Estadual do Rio Doce. In addition to these areas, there are a few records in the surroundings of Vitória (Espírito Santo state) and in highland areas along the state of Rio de Janeiro, in the municipalities of Barra Mansa, Volta Redonda and Cantagalo, but no additional samples from this latter area are known to date.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF80FFE3FDCA454FFDAFDA1C.taxon	description	urn: lsid: ipni. org: names: 77360848 - 1 Figs 5, 10	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF80FFE3FDCA454FFDAFDA1C.taxon	diagnosis	Diagnosis Oxalis idimae sp. nov. differs from O. decipiens by the glabrescent young stem (vs with abundant to very abundant, curved hairs), leaf blades abaxially glabrous (vs with abundant, appressed hairs), sometimes with occasional hairs on the margin (vs with abundant hairs), venation with the midrib impressed (vs canaliculate) adaxially, conspicuous secondary veins (vs slightly visible or inconspicuous), and areolation of good (vs moderate) development, inflorescences with (1 –) 2 single branches (vs with (1 –) 2 (– 3) usually bifid branches), flowers with white (vs yellow) flowers, and broadly ovoid (vs pyriform) capsules with the carpels lacking apical prolongations or prolonged to only ca 0.5 mm of their length (vs with the carpels prolonged for ca 2 mm of their length).	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF80FFE3FDCA454FFDAFDA1C.taxon	etymology	Etymology This new species honors the plant collector and amateur botanist Idimá Gonçalves Costa, who has recently discovered several new species of plants in the forest of northern Rio de Janeiro state, such as Anthurium idimae Theófilo & Nadruz (Valadares & Coelho 2017), Besleria aurea I. G. Costa & G. E. Ferreira (Ferreira et al. 2016), Conchocarpus hendrixii Groppo, I. G. Costa & Bruniera (Groppo et al. 2019), Eugenia asema I. G. Costa & M. C. Souza (Sobral et al. 2017), and Hippeastrum idimae Dutilh & R. S. Oliveira (Oliveira et al. 2017).	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF80FFE3FDCA454FFDAFDA1C.taxon	materials_examined	Type material BRAZIL – Rio de Janeiro • Cardoso Moreira, localidade de Vinhático; 21 ° 31 ′ 8.86 ″ S, 41 ° 37 ′ 18.01 ″ W; 238 m a. s. l.; 6 Mar. 2017; I. G. Costa 879; holotype: FLOR [FLOR 66532]; isotypes: HUEFS, RB, SPF. Other material examined	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF80FFE3FDCA454FFDAFDA1C.taxon	description	Description Unbranched or few-branched, erect subshrubs, 60 – 120 cm tall; young stem glabrescent, with occasional to sparse, curved to appressed hairs; older stem ochreous, terete, slightly striate longitudinally. Leaves pinnate-trifoliolate, arranged along the stem, densely grouped at stem apex, sometimes forming multiple pseudo-whorls, the internodes 5 – 40 mm long; the petioles 31 – 110 × 0.5 – 0.8 mm, slightly canaliculate adaxially, with occasional, appressed hairs, more densely in the proximal region, the base pulvinate, enlarged to ca 1.2 mm diam.; the rachis 10 – 28 mm long, similar to the petiole; petiolules ca 1 mm long, with sparse, appressed hairs; leaflet blades adaxially glabrous, abaxially glabrous, the margin sometimes with occasional hairs in the proximal part; membranous, adaxially green, abaxially lighter green. Venation: midrib impressed adaxially, impressed to slightly raised abaxially; secondary veins 5 – 8 pairs, conspicuous, impressed on both surfaces, sometimes very slightly raised abaxially, angle of divergence inconsistent; intercostal tertiary veins irregular-reticulate, exterior tertiary course looped, quaternary veins fabric irregular-reticulate, areolation of good development, free ending veinlets unbranched or with one branch. Terminal blade 54 – 110 × 24 – 48 mm, ovate to lanceolate, the apex acuminate, the base obtuse. Lateral leaflets opposite, the blades 31 – 73 × 15 – 33 mm, ovate to lanceolate, the apex acuminate, the base subsymmetrical to asymmetrical, rounded to almost truncate. Dichasial cymes cauliflorous, shorter than the leaves; the peduncle 6 – 65 mm long, slightly flattened laterally, with moderate, curved or appressed hairs; dichasial branches (1 –) 2, 0.5 – 8 mm long, each with the flowers (or scars) densely grouped along the entire length or with the proximal part elongated, and the scars far from the terminal flower; bracts 0.7 – 1.5 mm long, lanceolate to linear, abaxially with moderate to abundant, appressed hairs; bracteoles ca 0.5 mm long, triangular-ovate, with moderate, appressed hairs. Flower buds 4 – 4.5 × ca 1.5 mm, lanceolate, acuminate. Pedicel 3 – 6 mm long, articulated at base, leaving a persistent foot up to ca 0.5 mm long; with moderate to abundant, appressed hairs. Sepals greenish, ca 6 × 1.7 – 1.8 mm, lanceolate, the exposed part with sparse to moderate, appressed hairs, the apex acuminate. Corolla white, ca 10 mm diam., petals ca 10 mm long, each with two orange maculae above the throat; short-styled morph: filaments connate for ca 0.5 mm of their length; shorter filaments ca 3.5 mm long, glabrous, each with a basal knob, longer filaments ca 5 mm long, non-appendiculate, hispidule; pistil: ovary ca 0.7 mm long; styles ca 0.7 mm long, proximally hispidule; stigmas oblate; gynophore ca 0.5 mm long; long-styled morph: filaments connate for ca 0.5 mm of their length; shorter filaments ca 1.2 mm long, glabrous, each with a basal knob, longer filaments ca 3.5 mm long, non-appendiculate, hispidule in the distal ⅓; pistil: ovary ca 0.8 mm long; styles ca 3 mm long, erect, hispidule along the entire length; stigmas oblate; gynophore ca 0.3 mm long. Capsules ca 4.5 × 4.5 mm, broadly ovoid, glabrous, slightly shorter than the calyx lobes, the apex not prolonged or prolonged to ca 0.5 mm long; locules one-seeded, internally glabrous; seeds ca 2 × 1.2 mm, semi-obloid, with a honeycombed-foveolate surface.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF80FFE3FDCA454FFDAFDA1C.taxon	conservation	Preliminary conservation status assessment This species is only known from a few seasonally dry forest fragments in the northern part of Rio de Janeiro state, which has historically suffered from a steady conversion of forests in cultivated areas for agricultural activities or pastures for cattle farming. The species is not known from any protected area, and the only fragments where it occurs are privately-owned; thus, it may be suffering from both extent and quality loss. With an EOO of only 8.6 km ², it is suggested that this species should be considered as Critically Endangered following the IUCN criteria CR B 1 ab (iii) (IUCN 2012).	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF80FFE3FDCA454FFDAFDA1C.taxon	discussion	Remarks Costa et al. (2019) had access to one specimen of O. idimae sp. nov. (I. G. Costa 400, RB), but they decided to treat it under O. polymorpha subsp. polymorpha, which was distinguished from O. polymorpha subsp. tijucana by the leaves spacely distributed along the stem (vs grouped in a pseudo-whorl at stem apex). Oxalis idimae sp. nov. can be distinguished from all other species that are here segregated from O. polymorpha by the following combination of character states: glabrescent young stem, glabrous leaf blades (the margin sometimes with occasional hairs), inflorescences mostly cauliflorous, with white flowers, and capsules with the carpels without apical prolongation or prolonged to only ca 0.5 mm long. Moreover, it can be distinguished from O. decipiens, which also sometimes bears cauliflorous inflorescences, by several additional features (see Table 3).	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF80FFE3FDCA454FFDAFDA1C.taxon	distribution	Distribution and ecology This species is presumably endemic to the northern part of Rio de Janeiro state, where it is known only from seasonally dry forests.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF8DFFE4FDF644E7FE00DDDA.taxon	description	urn: lsid: ipni. org: names: 77360849 - 1 Figs 11 – 12	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF8DFFE4FDF644E7FE00DDDA.taxon	diagnosis	Diagnosis This new species is very similar to Oxalis tijucana, from which it can be distinguished by the leaflet blades abaxially with abundant, short appressed hairs along the midrib (vs glabrous or with occasional hairs along the midrib); terminal blades ≥ 2 × longer (vs up to 1.5 × longer) than the lateral ones, with 5 – 7 (vs 8 – 12) pairs of secondary veins, and inflorescences with the peduncle 9 – 50 mm long (vs 82 – 110 mm long).	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF8DFFE4FDF644E7FE00DDDA.taxon	etymology	Etymology The name of this species refers to the ʻPadre Estadual da Pedra Brancaʼ (Pedra Branca State Park, an important protection area where this species is known to occur (Fig. 12). In the tupi-guarani language, ʻitaʼ means ʻpedraʼ (the Portuguese word for rock) and ʻtingaʼ means ʻbrancaʼ (white, in Portuguese), thus the epithet ʻ itatingae ʼ.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF8DFFE4FDF644E7FE00DDDA.taxon	materials_examined	Type material BRAZIL – Rio de Janeiro • Rio de Janeiro, Prainha, “ Área de Proteção Ambiental da Pedra Branca ” [Pedra Branca Environmental Protected Area]; 23 ° 02 ′ 16 ″ S, 43 ° 30 ′ 25 ″ W; 23 Mar. 2015; P. Fiaschi et al. 4472; holotype: FLOR. Other material examined BRAZIL – Rio de Janeiro • Rio de Janeiro, “ Área de Proteção Ambiental Prainha, Trilha para o Cruzeiro do Sul ” [Prainha Environmental Protection Area, Trail to Cruzeiro do Sul]; 8 Apr. 2015; D. R. Gonzaga & C. Martins 516; RB • Rio de Janeiro, Camorim; 19 Dec. 1933; Excursão O. Sampaio Freire, Peckolt e Oswaldo Costa s. n.; R [70501] • Rio de Janeiro,; Camorim, Pedra da Rosilha, “ acesso pela estrada da Boca do Mato - Vargem Pequena ” [access via Boca do Mato - Vargem Pequena road]; 23 Jan. 2023; P. Feliz 372; RB • Rio de Janeiro,; Campo Grande, “ Batalhão de Operações Especiais de Fuzileiros Navais (Batalhão Tonelero) ” [Marine Special Operations Battalion (Tonelero Battalion)]; 22.8541 o S, 43.5859 o W; 25 Apr. 2017; A. L. Scudeler et al. 443; ESA, FLOR • Rio de Janeiro, Grumari; 2 Apr. 1984; V. F. Ferreira 3344; RB • Jacarepaguá, Vargem Grande, Mata de Lagôa; 150 – 350 m a. s. l.; 21 Apr. 1980; T. Plowman 10108; RB • Rio de Janeiro, Parque Municipal Ecológico da Prainha, “ subida para o mirante Cruzeiro do Sul ” [ascent to the Cruzeiro do Sul viewpoint]; ca 320 m a. s. l.; 13 Nov. 2003; fl; J. M. A. Braga et al. 7256; K n. v., MBM, NY n. v., RB • Rio de Janeiro, Parque Municipal Ecológico da Prainha, “ subida para o mirante Cruzeiro do Sul ” [ascent to the Cruzeiro do Sul viewpoint]; 7 Mar. 2024; st; J. C. Vasques et al. 86; FLOR • Rio de Janeiro, Restinga do Recreio dos Bandeirantes, Morro da Prainha; 4 Dec. 1978; G. Martinelli 5551; RB • Rio de Janeiro, Serra do Mendanha; ca 450 m a. s. l.; 27 Feb. 1969; D. Sucre & P. I. Braga 6386; RB.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF8DFFE4FDF644E7FE00DDDA.taxon	description	Description Unbranched or few-branched, erect subshrubs, 10 – 35 cm tall, with an elongated horizontal stem up to ca 30 cm long spreading under the leaf litter; young stem covered by scars of the fallen leaves and inflorescences; glabrescent, with sparse to moderate, short, curved or appressed hairs; older stem brownish, terete, smooth. Leaves pinnate-trifoliolate, densely grouped at stem apex, appearing arranged in a terminal pseudo-whorl, the internodes indistinct (<0.5 mm long), sometimes up to ca 8 mm long; the petioles 14 – 68 × ca 0.5 mm, canaliculate adaxially or only slightly flattened, adaxially with abundant, curved hairs, abaxially with occasional to sparse hairs, the base pulvinate, enlarged to ca 1 mm diam., articulated at 0.5 – 2 mm long; the rachis 6 – 21 mm long, similar to the petiole; petiolules ca 0.5 mm long, with hairs slightly larger and thicker than the petiole ones; leaflet blades adaxially glabrous, with hairs restricted to the ciliate margin; abaxially with abundant, short appressed hairs along the midrib; membranous to chartaceous, abaxially lighter colored than adaxially. Venation: midrib impressed to slightly canaliculate adaxially, impressed to slightly raised in the proximal part abaxially; secondary veins 5 – 7 pairs, inconspicuous, impressed on both surfaces, angle of divergence increasing towards the apex; tertiary and quaternary veins inconspicuous (not described). Terminal blade 45 – 108 × 17 – 46 mm, lanceolate to almost narrowly trullate, the base cuneate to obtuse, the margin plane, ciliate, the apex acuminate. Lateral leaflets opposite, the blades 17 – 54 × 12 – 29 mm, ovate to widely ovate, the base asymmetrical to strongly asymmetrical, the proximal side> 1.5 wider than the distal one, rounded to almost truncate, the apex acuminate to obtuse. Dichasial cymes axillary, shorter than the leaves; the peduncle 9 – 50 mm long, slightly flattened, with sparse to moderate (abundant), curved or appressed hairs; dichasial branches 2, 1 – 7 mm long, each with the flowers (or scars) densely grouped along the entire length, sometimes recurving the branches; bracts ca 0.5 mm long, triangular, abaxially with abundant, appressed hairs; bracteoles ca 0.5 mm long, triangular, with abundant, appressed hairs. Flower buds ca 6.5 × 2.8 mm, ovate to lanceolate, acuminate. Pedicel 5 – 7 mm long, articulated at base, leaving a persistent foot up to ca 0.5 mm long; with abundant, short, patent to slightly retrorse hairs, sometimes distally mixed with antrorse, longer hairs. Sepals light green, ca 7 × 1.7 – 2 mm, narrowly elliptic or lanceolate, symmetric to slightly asymmetric, the apex acute to rounded, sometimes mucronate, the exposed part with moderate, appressed hairs. Corolla dark yellow, ca 16 mm diam., petals ca 15 mm long, each with two orange maculae above the throat; short-styled morph: filaments connate for ca 1 mm of their length; shorter filaments ca 2.5 mm long, glabrous; longer filaments ca 4.5 mm long, non-appendiculate, distally hispidule; pistil: ovary ca 1 mm long; styles ca 3.5 mm long, erect, hispidule for the entire length; stigmas oblate; gynopohore ca 1 mm long; long-styled morph: filaments connate for ca 1.2 mm of their length; shorter filaments ca 2.5 mm long, glabrous, longer filaments ca 4 mm long, non-appendiculate, distally hispidule; pistil: ovary ca 1.2 mm long; styles ca 2.8 mm long, erect, hispidule for the entire length; stigmas oblate; gynophore ca 1 mm long; carpels uniovulate. Capsules ca 4 × 5.5 mm, obloid, glabrous, shorter than the calyx lobes, the apex prolonged for ca 1 mm of its length; locules one-seeded, internally glabrous; seeds ca 3 × 1.7 mm, semi-obloid, with a honeycombed-foveolate surface.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF8DFFE4FDF644E7FE00DDDA.taxon	conservation	Preliminary conservation status assessment Oxalis itatingae sp. nov. is restricted to preserved forests in the western part of Rio de Janeiro municipality (Fig. 12), the second largest Brazilian city, which suffers from a continuous historic decline of habitat quality and extent. It is known to occur in some protected areas, such as Parque Municipal Ecológico da Prainha, but this protection may not be enough to safeguard it from further declines, as this region is still subjected to illegal squatting for real estate development. With an EOO of 190 km 2 and an AOO of 24 km 2, this species should be conservatively treated as Endangered following the IUCN criteria EN B 2 ab (iii) (IUCN 2012).	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF8DFFE4FDF644E7FE00DDDA.taxon	discussion	Remarks Specimens belonging to this new species have been previously treated as O. polymorpha subsp. tijucana by Fiaschi (2014), Costa et al. (2019), and Richetti et al. (2023). However, during fieldwork in the municipality of Rio de Janeiro, we were able to locate one population of this latter taxon, which is here elevated to species level (as O. tijucana (Lourteig) Fiaschi). The main differences between O. itatingae sp. nov. and O. tijucana are presented in the diagnosis above (see also Table 3).	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF8DFFE4FDF644E7FE00DDDA.taxon	distribution	Distribution and ecology This species is restricted to rainforests in the surroundings of Rio de Janeiro city, especially in Camorim, Campo Grande, and Jacarepaguá neighborhoods (Fig. 12), where it is only found in shady environments of preserved forests.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF8AFFDAFE4C43A5FEBFDCF9.taxon	description	urn: lsid: ipni. org: names: 77360850 - 1 Figs 12 – 13	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF8AFFDAFE4C43A5FEBFDCF9.taxon	materials_examined	Type material BRAZIL – Rio de Janeiro • Rio de Janeiro, Parque Nacional da Tijuca, Serra dos Pretos Forros, Represa dos Ciganos; 200 – 300 m a. s. l.; 30 Sep. 1977; fl, fr; G. Martinelli et al. 3196; holotype: P [P 02440300]; isotypes: RB [RB 00271307, RB 00585541], SPF [SPF 00197792]. Other material examined BRAZIL – Rio de Janeiro • Rio de Janeiro, Cascadura, Serra da Bica; Nov. 1897; fl; E. Ule 4537; R • Rio de Janeiro, Serra da Bica, “ par Ribeiro ”; 21 Feb. 1883; A. F. M. Glaziou 13648 a; P • Rio de Janeiro, Jacarepaguá, Curicica, FioCruz, “ caminho da cachoeira ” [waterfall path]; 22 ° 56 ′ 37.17 ″ S, 43 ° 24 ′ 51.72 ″ W; 13 Apr. 2015; fl; J. P. Costa s. n.; HUEFS [217077], RBR [37031] • same data as for preceding; 7 Mar. 2024; fl, fr; J. C. Vasques et al. 85; BAL, FLOR, RB, RBR, SPF.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF8AFFDAFE4C43A5FEBFDCF9.taxon	description	Description Unbranched, erect subshrubs, 25 – 30 cm tall, with the stem sometimes spreading under the leaf litter; young stem glabrescent, with sparse, appressed hairs; older stem brownish, terete, longitudinally striate. Leaves pinnate-trifoliolate, densely grouped at stem apex, appearing arranged in a terminal pseudo-whorl, but sometimes with a few leaves inserted below, the internodes 1 – 25 mm long; the petioles 49 – 105 × 0.5 – 1 mm, canaliculate and with abundant, curved hairs, along the margin adaxially, abaxially glabrous or with occasional hairs, the base pulvinate, enlarged to ca 2.5 mm diam., articulated at 1 – 2 mm of its length; the rachis 6 – 15 mm long, similar to the petiole; petiolules thick, 1 – 1.5 mm long, adaxially with hairs slightly larger and thicker than the petiole ones; leaflet blades adaxially glabrous; abaxially glabrous or with occasional hairs along the midrib and sparse hairs usually hiding under the revolute margin; membranous to chartaceous, abaxially lighter colored than adaxially. Venation: midrib canaliculate adaxially, at least in the proximal part, raised abaxially; secondary veins 8 – 12 pairs, conspicuous, impressed on both surfaces, angle of divergence increasing towards the apex; intercostal tertiary veins irregular-reticulate, exterior tertiary course looped, quaternary veins fabric irregular-reticulate, areolation moderately developed, free ending veinlets mostly with one branch. Terminal blade 100 – 160 × 29 – 48 mm, narrowly elliptic to lanceolate, the base attenuate to cuneate, the margin plane to revolute, the apex acute to acuminate. Lateral leaflets opposite, the blades 90 – 140 × 24 – 36 mm, lanceolate, the base asymmetrical to strongly asymmetrical, cuneate to obtuse, the apex acute to acuminate. Dichasial cymes axillary, shorter than the leaves; the peduncle 82 – 110 mm long, laterally flattened, with occasional to sparse, curved hairs; dichasial branches 2, up to ca 22 mm long, each with the flowers (or scars) densely grouped along the entire length; bracts ca 1 mm long, triangular, abaxially with abundant, appressed hairs; bracteoles ca 0.8 mm long, triangular, with abundant, appressed hairs. Flower buds ca 6.5 × 2.5 mm, lanceolate-acuminate. Pedicel 4.5 – 7 mm long, articulated at base, leaving a persistent, subsessile foot; with sparse to moderate, curved to appressed, antrorse hairs. Sepals light green, 7 – 10.5 × 1.5 – 2.4 mm, lanceolate to narrowly oblong, symmetric to slightly asymmetric, the apex acuminate to obtuse, sometimes mucronate, the exposed part with moderate, curved or straight hairs, sometimes with hairs ca 1 mm long. Corolla yellow, ca 18 mm diam., petals ca 13 mm long, each with two orange maculae above the throat; short-styled morph: filaments connate for ca 2 mm of their length; shorter filaments ca 5 mm long, glabrous; longer filaments ca 7 mm long, non-appendiculate, distally hispidule; pistil: ovary ca 1.2 mm long; styles ca 1.5 mm long, erect, glabrous; stigmas oblate; gynophore ca 1.5 mm long; long-styled morph: filaments connate for ca 1.5 mm of their length; shorter filaments ca 2.7 mm long, glabrous, longer filaments ca 4.5 mm long, non-appendiculate or very slightly appendiculate at ca 2 mm long, distally hispidule; pistil: ovary ca 1.2 mm long; styles ca 4 mm long, erect, hispidule for the entire length; stigmas oblate; gynophore ca 1.2 mm long; carpels uniovulate. Capsules ca 6 × 5.5 mm, obloid to broadly depressed ovoid or pyriform, glabrous, as long or slightly longer than the calyx lobes when fully developed, the apex prolonged for 1.5 – 2 mm of its length; locules one-seeded, internally glabrous; seeds 3.2 – 3.5 × 2 – 2.2 mm, semi-broadly ovoid, with a honeycombed-foveolate surface.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF8AFFDAFE4C43A5FEBFDCF9.taxon	conservation	Preliminary conservation status assessment Oxalis tijucana is restricted to preserved forests in the western part of Rio de Janeiro municipality, where it occurs in more urbanized areas than O. itatingae sp. nov. (Fig. 12); moreover, its EOO = 23 km 2 and AOO = 12 km 2 are much smaller than those of the latter species. It is very likely that this species no longer occurs in Serra da Bica, a locality where it was only collected in the late 19 th century, and which is now an area dominated by criminal groups and only partially covered by degraded forests. The indication that O. tijucana has been suffering a continuous decline of habitat quality and extent suggests that it should be categorized as Critically Endangered following IUCN criteria CR B 2 ab (iii) (IUCN 2012).	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF8AFFDAFE4C43A5FEBFDCF9.taxon	discussion	Remarks This taxon was originally proposed as Oxalis polymorpha subsp. tijucana by Lourteig (1994) based on the presence of glabrous leaflets and canaliculate petioles, with the margin densely hirsute-ciliate. Other than these features, the species also differs from O. polymorpha by the leaves densely grouped at stem apex, forming a single terminal pseudo-whorl (vs leaves arranged along the stem), the pedicels with abundant, short, retrorse hairs (vs abundant, appressed to curved, antrorse hairs), and the obloid fruits with the carpels prolonged for ca 1 mm long (vs very broadly ovoid to broadly depressed ovoid fruits with the carpels prolonged for ca 0.5 mm long) (see Table 3). Molecular phylogenetic evidence now available (Fig. 3) points to a sister-group relationship between a clade formed by O. inopinata plus O. itatingae sp. nov. and a larger clade that includes all remaining species of O. sect. Holophyllum. Due to its morphological similarity to O. itatingae, O. tijucana very likely also belongs to this first, smaller clade. Thus, its placement under O. polymorpha (and in O. sect. Polymorphae, Fig. 3) would not be supported, even though O. tijucana (and O. itatingae) have three-foliolate leaves, while O. inopinata and the remaining species of O. sect. Holophyllum are unifoliolate (Fiaschi et al. 2024). Among the morphological features that may support the placement of these two, three-foliolate species (O. tijucana and O. itatingae), together with O. inopinata (see fig. 11 in Fiaschi et al. 2024) are the canaliculate petioles with ciliate margin, the glabrous leaflet blades with conspicuously ciliate margins, and the inflorescences with dichasial branches bearing densely grouped bracteoles along the entire length (Fig. 13 K).	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
9E06820BFF8AFFDAFE4C43A5FEBFDCF9.taxon	distribution	Distribution and ecology This species is restricted to rainforests in the surroundings of Rio de Janeiro city, especially in Cascadura, Curicica and Jacarepaguá neighborhoods, where it is commonly found in shady environments of preserved forests.	en	Fiaschi, Pedro, Cabral, Fernando Santos, Caballero, Leonardo Ronald Gaspar, Lima, Duane Fernandes (2025): Updating the taxonomy of polymorphic plant taxa: six Atlantic Forest species segregated from the widely circumscribed Oxalis polymorpha Mart. ex Zucc. (Oxalidales, Oxalidaceae). European Journal of Taxonomy 989: 144-188, DOI: 10.5852/ejt.2025.989.2891, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2891/13109
