Jamesonia (Pteridaceae) in Brazil

Abstract: Jamesonia is a genus of Neotropical ferns that comprises about 50 species, distributed from Mexico to Uruguay. In spite of this wide distribution, this group is more diverse in Andean páramos and subpáramos. Due to the recent changes in its circumscription, with the junction of Eriosorus and segregation of Tryonia, the objective of this work was to carry out the taxonomic study of Jamesonia for Brazil, in order to elaborate its monograph to the Flora of Brazil 2020. This study was based on morphological analyses of specimens deposited in 25 Brazilian herbaria, plus online images of types, field expeditions in the southern and southeastern regions of Brazil, revision of the literature, and scanning electronic microscopy of the spores. Seven species and two hybrids were recognized: J. biardii, J. brasiliensis, J. cheilanthoides, J. flexuosa, J. insignis, J. osteniana, J. rufescens, J. brasiliensis × J. cheilanthoides, and J. ×intermedia, respectively. A distinct specimen, from the border of Brazil (Amazonas) and Venezuela, was treated as Jamesonia sp., due to the presence of only one material. Identification key, descriptions and illustrations are provided for the species and hybrids, as well as, geographical distribution data, comments, list of selected material examined for each taxon, and a full list of all exsiccatae analyzed. We also present an identification key for the genera Jamesonia and Tryonia.


Introduction
Thus, the main goal of the present study is to present a taxonomic treatment of Jamesonia for Brazil, to provide information for a better understanding and identification of its species, and contribute with the project Flora of Brazil 2020, coordinated by the Instituto de Pesquisas Jardim Botânico do Rio Janeiro (JBJR).
Field expeditions were carried out in the states of Minas Gerais, Rio de Janeiro, and Rio Grande do Sul. The specimens were collected according to the technical recommendations proposed by Fidalgo & Bononi (1984) and incorporated in the Herbaria of the Instituto de Botânica (SP) and of the Departamento de Botânica, Universidade de São Paulo (SPF).
The terminology of vegetative and reproductive structures followed Lellinger (2002) and Tryon & Lugardon (1990). Habitat characteristics and ecological aspects were described from the information present in the herbarium labels, direct observations in the field, and bibliography.
Spore images of all taxa were taken with a Scanning Electronic Microscope (SEM). The spores of specimens stored in the SP herbarium were fixed on stubs using double-sided tape and were not submitted to any previous chemical treatment. The stubs were then coated with gold and analyzed under the SEM (Model: Philips XL30).
The distribution maps were drawn using the software ArcGIS v. 10.5 (ESRI 2016). The geographical coordinates were taken from the herbarium labels or taken during the field works. For the materials without information on geographic coordinates, the coordinates of the municipality were estimated using Google Earth (www.google.com/intl/ en/earth/). The estimated coordinates were cited in brackets in the material examined. The shapefile of Brazil and the Conservation Units were obtained from IBGE (2015) and ICMBio (2019) websites, respectively.
In the selected material examined, only one specimen per state was listed and the states were cited in alphabetic order. All specimens examined (which include those not cited in the select material examined section) are listed in Appendix I (the number in parentheses corresponds to the number of the species in the taxonomic treatment).

Results
Due to the recent changes in the circumscription of Jamesonia and segregation of Tryonia, confusions can be generated to identify these taxa, so the key below can be used to distinguish them.
Tryonia myriophylla is easily distinguished from Jamesonia biardii by its stramineous petioles (distally) and rachises (vs. dark brown); pinnae moderately to densely covered by glandular hairs and less often eglandular on both surfaces (vs. surfaces glabrous to sparsely covered eglandular hairs Plants rupicolous or terrestrial. Rhizomes short-creeping, 0.7−1.9 mm diam., dark brown, moderately to densely covered by hairs and rigid bristles, the hairs reddish brown, multicellular, glandular, the apical cell globose to slightly bulbous, 1.7−3.0 mm long, the bristles reddish brown, with darker-colored thickened transverse cell walls, apex long-filiform, base with 2 cells wide, apical cell globose to slightly bulbous, 1.7−2.6 mm long. Fronds erect to arcuate, indeterminate growth, 26.0−61.5 × 0.4−0.7 cm; petioles cylindrical or semi-cylindrical, adaxially grooved, 4.0−7.5 cm × 0.4−0.6 mm, dark brown, shiny, glabrous to sparsely covered by hairs on both surfaces, the hairs 0.5−3.0 mm long, eglandular, hyaline, tortuous, multicellular, the apical cell elongated with apex rounded; laminae pinnate, linear, 21−54 × 0.4−0.7 cm, with apical bud densely covered by hairs, the hairs eglandular similar to those of the petioles, coriaceous; rachises straight, ellipsoidal or triangular, dark brown, adaxially moderately covered by the hairs, abaxially densely covered by hairs, the hairs eglandular similar to those of the petioles; pinnae reflexed to slightly ascending, orbicular, 0.1−0.3 × 0.2−0.3 cm, usually subopposite or sometimes alternate at lamina base, abrupt to gradually tapering proximally, sometimes gradually tapering towards the apex, short-stalked, the stalk 0.4−0.7 mm long, 0.1−0.2 mm diam., cylindrical, dark brown, curved, adaxial surface of pinnae sparsely to moderately covered by hairs, the hairs eglandular similar to those of the petioles, abaxial surface of pinnae densely covered by hairs, the hairs ca. 0.5−1.5 mm long, eglandular, hyaline, tortuous, 2−4-celled, apical cell elongated with apex rounded, the margins entire, sometimes undulate, strongly recurved, ciliate, whitish; veins usually furcate, sometimes simple, reaching or not the lamina margin. Sori usually on the proximal portion of the pinnae, or sometimes spread along of all abaxial surface of the pinnae; spores dark brown, proximal surface with coalescent tuberculate, mainly near trilete aperture, distal surface slightly rugose to laevigate, 48.0−53.5 μm diam. Distribution and ecology: Jamesonia brasiliensis occurs in cracks of rocks partially shaded in the Itatiaia Mountains (Rio de Janeiro and Minas Gerais), at 2200−2600 m elevation. It is a threatened species (critically endangered -CR) according to the Red List of Brazilian Flora, version 2012.2 (CNCFlora 2019).
This species has been considered endemic of Itatiaia (Brazil), however, Tryon (1962)  Plants rupicolous or terrestrial. Rhizomes short-creeping, 0.2−2.6 mm diam., dark brown, moderately to densely covered by hairs and rigid bristles, the hairs reddish brown, multicellular, glandular, apical cell globose to slightly bulbous, 1.0−2.3 mm long, the bristles reddish brown to dark brown, with darker-colored thickened transverse cell walls, apex long-filiform, base with 2 or 3 cells wide; apical cell globose to slightly bulbous, 0.7−1.6 mm long. Fronds erect to arcuate, indeterminate growth, 24.0−120.0 × 0.6−1.5 cm; petioles cylindrical or semi-cylindrical, adaxially grooved, sometimes plane, 5.0−17.0 cm × 0.4−1.0 mm, dark brown, shiny, glabrous to sparsely covered by hairs on both surfaces, the hairs of the proximal portion similar to those the rhizomes, of distal portion the hairs with 0.3−2.0 mm long, eglandular, hyaline or dark brown, tortuous, multicellular, the apical cell elongated with apex rounded; laminae pinnate-pinnatisect, linear, 19.0−113.0 × 0.6−1.5 cm, with a small apical bud moderately to densely covered by hairs, the hairs eglandular similar to those of distal portion of the petioles, chartaceous; rachises straight, semi-cylindrical, adaxially grooved, dark brown, moderately to densely covered by hairs on both surfaces, the hairs eglandular similar to those of the distal portion of the petioles; pinnae patent to slightly ascending, ovate to triangular, 0.3−1.2 × 0.3−0.7 cm, alternate, gradually tapering proximally, sometimes gradually tapering towards the apex, short-stalked, the stalk 0.4−1.7 mm long, 0.2−0.5 mm diam., cylindrical, dark brown, straight, sometimes curved, adaxial surface of pinnae sparsely to moderately covered by hairs, abaxial surface of pinnae sparsely to moderately covered by hairs on the veins, the hairs eglandular similar to those of the distal portion of the petioles; ultimate segments bifurcate, sometimes simple, margins entire, plane, sometimes recurved, whitish; veins usually furcate, sometimes simple, reaching or not the laminae margin. Sori along the veins or sometimes spread along of all abaxial surface of the pinnae; spores dark brown, proximal surface tuberculate, mainly near trilete aperture, distal surface tuberculate, 51.5−54.0 μm diam.
Distribution and ecology: Jamesonia cheilanthoides occurs in Bolivia, Brazil, Peru, and Tristan da Cunha Island, mainly at 2400−3900 m elevation (Tryon 1970). In Brazil, it can be found in cracks of rocks partially shaded in the Itatiaia Mountains (Rio de Janeiro and Minas Gerais States), at 2300−2500 m elevation. It is a threatened species Jamesonia cheilanthoides is characterized by having pinnatepinnatisect and linear fronds, with indeterminate growth (with small apical bud), ovate to triangular and chartaceous pinnae, abaxially sparsely to moderately covered by hairs on veins, the hairs eglandular, hyaline, tortuous, multicellular, apical cell elongated with apex rounded, and straight rachises.
According to the available online image of the type (S-P barcode S-P6352), the collection site is Mauritius Islands, which was interpreted as an error. This specimen was actually collected in the Tristan da Cunha Island (Tryon 1970).
According to Tryon (1970), this species shows high chromosome number (n=174) and considerable morphological variation, mainly due to hybridization. Plants rupicolous or terrestrial. Rhizomes short-creeping, 1.2−2.1 mm diam, dark brown, moderately covered by hairs and rigid bristles, the hairs reddish brown, multicellular, glandular, the apical cell globose to slightly bulbous, 1.7−2.3 mm long, the bristles reddish brown to dark brown, with darker-colored thickened transverse cell walls, apex long-filiform, base with 2−7 cells wide, apical cell globose to slightly bulbous, 2.7−3.2 mm long. Fronds erect to arcuate, indeterminate growth, rarely with determinate growth, 41.0−77.0 × 0.5−2.3 cm; petioles cylindrical or semi-cylindrical, adaxially grooved, 14.0−22.0 cm × 0.6−1.0 mm, dark brown, glabrous or sparsely covered by hairs on both surfaces, the hairs in the proximal portion similar to those the rhizomes, in distal portion hairs with 0.5−2.5 mm long, eglandular, hyaline, tortuous, multicellular, the apical cell elongated with apex rounded; laminae pinnate-pinnatifid to pinnate-pinnatisect, less frequent pinnate, linear, 24.0−53.0 × 0.5−2.3 cm, with apical bud moderately to densely covered by hairs, the hairs eglandular similar to those of the distal portion of the petioles, chartaceous to coriaceous; rachises straight, ellipsoidal, triangular or more often semi-cylindrical, adaxially grooved, dark brown, sparsely to densely covered by hairs on both surfaces, the hairs eglandular similar to those of the distal portion of the petioles; pinnae reflexed to slightly ascending, oblong, ovate or orbicular, 0.3−1.4 × 0.2−0.8 cm, alternate to subopposite, abrupt to gradually tapering proximally, sometimes gradually tapering towards the apex, short-stalked, the stalk 0.8−1.6 mm long., 0.3−0.4 mm diam., cylindrical, dark brown, straight to curved, adaxial surface of pinnae sparsely to moderately covered by hairs, abaxial surface of the pinnae moderately to densely covered by hairs, the hairs eglandular similar to those of the distal portion of the petioles; ultimate segments orbicular in the proximal portion of the pinnae, ovate in distal portion of the pinnae, the margins entire, sometimes undulate, recurved or not, whitish; veins usually furcate, sometimes simple, reaching or not the laminae margin. Sori along the veins; spores dark brown, proximal surface with coalescent tuberculate, mainly near trilete aperture, distal surface slightly rugose to laevigate, 50. The specimens hybrid between Jamesonia brasiliensis × J. cheilanthoides are easily recognized by their aborted or irregular spores and by the intermediate morphology of the plants between the parental species. Sometimes, it is more like one of the parents (pinnae orbicular coriaceous, like in J. brasiliensis) or with pinnae ovate to triangular, chartaceous (like in J. cheilanthoides)). The spores are badly formed due to the exaggerated development of equatorial expansion (Sylvestre 1995;Condack 2006). Brade (1954) treated the hybrid as Gymnogramma elongata var. itatiaiensis and as G. jamesonioides, when comparing these plants with Jamesonia brasiliensis, which are very similar, differing, however, by the herbaceous textured of the leaves. Tryon (1970) observed that Jamesonia cheilanthoides and J. brasiliensis growing on the edges of the same rock, the first one mainly on the shaded sides or under the suspended rock, and the second in sunny and exposed places. In these places, where these two species occur nearby, there are aggregations of individuals with intermediate  characteristics and with aborted or irregular spores (Tryon 1970). Some of these forms were recognized as taxonomically distinct (species or varieties), when disassociated from the site of their collection (such as Brade 1954). However, they were interpreted by Tryon (1970)  Plants terrestrial. Rhizomes short-creeping, 2.5−4.0 mm diam., dark brown, densely covered by hairs and rigid bristles, the hairs reddish brown, multicellular, eglandular (rarely glandular), the apical cell elongated with apex rounded, rarely globose, 0.7−2.3 mm long, the bristles reddish-brown to dark brown, with darker-colored thickened transverse cell walls, apex long-filiform, base with 4−6 cells wide, apical cell elongated with apex rounded, less frequent globose, 1.2−3.0 mm long. Fronds scrambling or scandent, erect in young (rarely in older plants), indeterminate growth, (sometimes exceeding 4 m length); petioles semi-cylindrical, adaxially grooved, 24.0−88.0 × 0.6−1.7 mm (incomplete plant measures), dark brown, glabrous to sparsely covered by hairs, mainly in groove, the hairs 0.2−1.7 mm long, eglandular, dark brown or hyaline, tortuous, multicellular, the apical cell elongate with apex rounded; laminae 3-pinnate to 1−2-pinnatisect to 6-pinnate, triangular, 32.0−60.0 × 12.0−24.0 cm (incomplete plant measures), membranaceous to chartaceous; rachises flexuous, semi-cylindrical, adaxially grooved, dark brown, abaxially and adaxially glabrous or with sparse hairs, mainly in groove, the hairs eglandular similar to those of the petioles; pinnae usually ascending, triangular, 6.0−28.0 (43.0) × 3.0−11.0 (13.0) cm, alternate, gradually tapering towards the apex (pinnatisect), stalked, the stalk 2.0−17.0 mm long, 0.5−2.0 mm diam, semi-cylindrical, adaxially grooved, dark brown, straight, adaxial surface of pinnae glabrous to sparsely covered by hairs, abaxial surface of the pinnae sparsely covered by hairs, mainly in the ultimate segments near sporangia, and on veins, the hairs eglandular similar to those of the petioles; costae flexuous, semi-cylindrical, adaxially grooved, dark brown, glabrous to sparsely covered by hairs on both surfaces, mainly in groove, the hairs eglandular similar to those of the petioles; pinnules triangular to ovate, 2.0−12.0 × 1.5−5.0 cm; costules flexuous, semicylindrical, adaxially grooved, dark brown, glabrous or sparsely covered by hairs, mainly in groove, the hairs eglandular similar to those of the petioles; segments triangular, 0.8−1.2 × 0.3−0.7 cm; ultimate segments bifurcate, sometimes simple, the margin entire, plane, whitish; veins usually furcate, not reaching the laminae margin. Sori on the veins in the proximal or distal portion of the ultimate segments; spores dark brown, proximal surface with coalescent ridges, mainly near trilete aperture, distal surface laevigate, 43. Jamesonia flexuosa is recognizes by its 3-pinnate-1−2-pinnatisect to 6-pinnate very divided, scrambling or scandent laminae, with indeterminate growth (can reach up to 4 m in length), triangular, oblong or lanceolate, membranaceous to chartaceous pinnae, adaxial and adaxial surface glabrous or moderately covered by hairs, the hairs eglandular, apical cell are elongated with apex rounded, flexuous rachises, costa, and costule, bifurcate ultimate segments.
According to Tryon (1970), there are many variants of this species, which are products of hybridization with other taxa. Recently, one variety of this species established by the author has been recognized as a distinct species, Jamesonia galeana (A.F.Tryon) A.Rojas (in Rojas-Alvarado 2017a). However, the segregation of this taxon was based only on the morphology.
In the specimens analyzed, we can observe a variation in the color of the petioles, rachises, costa, and costule. In the Brazilian and Venezuelan specimens, they are dark brown, whereas in the specimens from Colombia, Ecuador, and Bolivia they are stramineous. The gathering by M. Sundue et al. 1715 (RB), from Costa Rica, presents rachises moderately covered by hairs on both surfaces.
According to Salino & Viveros (2012), the plants from Minas Gerais State (Serra do Caraça) present glandular hairs on the laminae, mainly on the veins, which have small and globular apical cells, almost inconspicuous. The verified specimens from this locality and those from Amazonas and Roraima States, do not present glandular hairs on the lamina. Glands are rarely seen in the bristles and hairs of the rhizomes, in specimens collected in Serra do Caraça.
6. Jamesonia insignis (Mett.) Christenh., Plants terrestrial or rupicolous. Rhizomes short-creeping, 0.3−3.5 mm diam, dark brown, densely covered by hairs and rigid bristles, the hairs dark brown, multicellular, glandular, the apical cell globose, 0.3−3.0 mm long, the bristles dark brown, with darker-colored thickened transverse cell walls, apex long-filiform, base with 2−6 cells wide, apical cell globose, 3.0−3.7 mm long. Fronds erect or more often semiscandent, indeterminate growth, 35.0−105.0 × 6.0−20.5 cm; petioles semi-cylindrical, adaxially grooved, rarely plane, 16.0−63.0 cm × 1.0−2.0 mm, dark brown, shiny, sparsely to moderately covered by hairs on both surfaces, the hairs in the proximal portion similar to those of the rhizomes, at distal portion the hairs with 0.4−0.9 mm long, glandular or eglandular, hyaline to dark brown, sometimes bicolorous, erect, multicellular, the apical cell globose or elongated with apex rounded; laminae 2-pinnate-pinnatifid to 3-pinnate-pinnatisect, (rarely) pinnatepinnatisect, triangular to elongate-triangular, 8.0−42.0 × 4.5−20.5 cm, with apical bud densely covered by hairs, the hairs eglandular similar to those at distal portion of the petioles, chartaceous; rachises flexuous, sometimes semi-flexuous, semi-cylindrical, adaxially grooved, dark brown, moderately covered by hair on both surfaces, especially in the axils of the pinnae, the hairs eglandular similar to those of the petioles; pinnae proximal usually reflexed or patent, distal ascending, triangular, the basiscopic side slightly larger, 2.1−17.5 × 1.2−8.3 cm, alternate, rarely sub opposite, gradually tapering towards the apex (pinnatisect to pinnatifid), long-stalked, the stalk 2.3−11.0 mm long, 0.1−0.7 mm diam., semi-cylindrical, adaxially grooved, dark brown, straight, adaxial surface of pinnae moderately covered by hairs, mainly between the veins, abaxial surface of pinnae moderately to densely covered by hairs mainly on veins, the hairs eglandular similar to those of the petioles; costae flexuous, semi-cylindrical, adaxially grooved, dark brown, moderately covered by hairs on both surfaces, the hairs eglandular similar to those of the petioles; pinnules ovate to triangular, 1.0−4.0 × 0.7−2.6 cm, alternate, short-stalked, the stalk 0.6−8.0 mm long, 0.6−0.7 mm diam., semi-cylindrical, adaxially grooved, dark brown, straight; ultimate segments ovate or orbiculate, margins crenate to denticulatecrenate, usually plane, sometimes slightly recurved, whitish, with hairs eglandular similar to those of the petioles; veins furcate, reaching the lamina margin. Sori on the veins in distal portion of the segments; spores dark brown, proximal surface with coalescent ridges, mainly near trilete aperture, distal surface slightly rugate, 67.1−68.0 μm diam. Distribution and ecology: Jamesonia insignis occurs only in Brazil in the states of Minas Gerais, Paraná, Rio de Janeiro, and São Paulo, in moist and shady places in the cloud forest, rock fields, and high altitude fields, close to outcrops, at 1000−2000 m elevation. There is no record of occurrence for this species in the state of Espírito Santo (in the herbaria visited), but it is estimated that it occurs in this state. It is a threatened species ( Jamesonia insignis is characterized by having 2-pinnate-pinnatifid to 3-pinnate-pinnatisect, triangular fronds, triangular and chartaceous pinnae, with adaxial and abaxial surfaces moderately covered by hairs, the hairs eglandular, hyaline to brown, sometimes bicolorous, erect, apical cell elongated with apex rounded, flexuous rachises, ovate or orbiculate ultimate segments, with several superficial lobes, and the margins crenate to denticulate-crenate. The presence of this species in the state of Paraná has been recently confirmed in a checklist of ferns and lycophytes from the highlands of the Pico Paraná State Park (Pereira & Labiak 2018). This is the southernmost location of its distribution. Some studied specimens present morphological variations: The plants from Paraná State (p.e., V. Ariati et al. 1220;J.B.S. Pereira et al. 274) are smaller and less divided (pinnate-pinnatisect), whereas few specimens of the Rio de Janeiro State (p.e., Santos-Lima 417; A.C. Brade s.n. (RB 33995)) have robust leaves with few lobes and fully brown hairs on the fronds. According to Tryon (1970), these variations probably reflect different levels of ploidy, but this hypothesis was not tested in the present account. Additionally, some fronds have flexuous rachises more demarcated than others.
The plants from Paraná can be confused with Jamesonia rufescens by the shape and size of the frond and ultimate segments, as well as by the crenate margin of the segments. However, it is distinguished by presence of glandular hairs and bristles on the rhizome, whereas J. rufescens has eglandular hairs and bristles. In addition, J. insignis has flexuous or slightly flexuous rachises (vs. straight in J. rufescens).

Distribution and ecology:
This hybrid taxon is endemic to Brazil and occurs only in the Serra dos Órgãos, in the Rio de Janeiro State. It grows at the edge of the trail to the Pico do Alcobaça, at 1650−1670 m elevation. The soil of this region is shallow, dark, and humid, arranged under a rocky slab. The plant was found between grasses and bromeliads.  Jamesonia ×intermedia is recognized by its 2-pinnate-pinnatisect to 3-pinnate-pinnatifid laminae, triangular and coriaceous pinnae, with adaxial surface glabrous or with sparse hairs, abaxial surface moderately covered by hairs, mainly on veins, the hairs eglandular, hyaline, tortuous, apical cell elongated with apex rounded, rachises, costa and costule flexuous and stramineous in young plants and brown in adult plants, and elongate-triangular to ovate ultimate segments, with several superficial lobes, with crenate margins.
Distribution and ecology: Jamesonia osteniana occurs in humid ravines along roadsides and river margins in the Rio Grande do Sul State (Brazil). Also, in Uruguay between rocks, at 50−140 m elevation. In  Viamão (Rio Grande do Sul), a small population was verified in a ravine of roadside, between grasses, in an area of cattle pasture and cultivation of Pinus. The plants were present in small spots without vegetation around, with exposed soil. It is a plant with annual sporophyte (the sporophyte is "visible" and fertile, usually from September to January. The period between September and October is the best one to collect this species. This species was included in the list of priority species for conservation in Uruguay, because it is considered a threatened species (Soutullo et al. 2009).
This taxon was described as part of the genus Anogramma, but Nakazato & Gastony (2003), based on molecular phylogenetic analyses, found that A. osteniana is sister and more closely related to Jamesonia and Eriosorus. This species forms a monophyletic group together another species of these two genera and with high support (ML = 100). So it was combined into Jamesonia. The similarity of the laminae and spores have already been indicative of the phylogenetic proximity of A. osteniana with Jamesonia and Eriosorus (Nakazato & Gastony 2003).
However, this species can be distinguished from other Jamesonia by the presence of erect rhizome, covered only by glandular hairs and absence of bristles; by the color of the rachis stramineous, rather than brown or dark brown; and by the short (few cells) glandular hairs of the laminae. Additionally, this species is annual and occurs at 50−140 m elevation (vs. perennial plants and growing in high elevations). The phylogenetic position of this species is being studied by the present authors and the results will be part of another paper. 9. Jamesonia rufescens (Fée) Christenh., Phytotaxa 19: 21. 2011. Gymnogramma rufescens Fée, Gen. Filic.: 181, t. 19C, Fig. 3 15. Plants rupicolous or terrestrial. Rhizomes short-creeping, 1.0−3.0 mm diam, dark brown, moderately to densely covered by hairs and bristles, the hairs reddish brown to black, multicellular, eglandular, the apical cell elongated with apex rounded, 1.0−1.4 mm long, the bristles dark brown to black, with darker-colored thickened transverse cell walls, apex long-filiform, base with 2 cells wide, apical cell elongated with apex rounded, 1.0−1.4 mm long. Fronds erect to arcuate, determinate growth, 6.0−47.0 × 1.1−8.0 cm; petioles semi-cylindrical, adaxially grooved, 1.4−36.0 cm × 0.6−1.0 mm, dark brown, moderately to densely covered by hairs on both surfaces, the hairs at the proximal portion  similar to those of the rhizome, at distal portion the hairs with 1.0−2.0 mm long, eglandular, brown to hyaline, sometimes bicolorous, erect to slightly tortuous, multicellular, the apical cell elongated with apex rounded; laminae pinnate-pinnatisect to pinnate-pinnatifid, triangular, sometimes ovate, 2.0−12.3 × 1.1−8.0 cm, chartaceous to coriaceous; rachises straight, semi-cylindrical, adaxially grooved, dark brown, moderately to densely covered by hair on both surfaces, the hairs eglandular similar to those of the distal portion of the petioles; pinnae patent to ascending, triangular to ovate, the basiscopic side slightly larger, 1.1−4.5 × 0.5−3.0 cm, alternate to opposite, gradually tapering towards the apex (pinnatisect to pinnatifid), sessile to short-stalked, the stalk 0.2−2.0 mm long., 0.7−1.3 mm diam, semi-cylindrical, adaxially grooved, dark brown, often with laminae decurrent, straight, adaxial surface of pinnae moderately to densely covered by hairs, abaxial surface of pinnae moderately to densely covered by hairs, mainly on veins, the hairs eglandular similar to those at distal portion of the petioles; ultimate segments ovate, the margin crenate, plane, sometimes recurved, whitish, with hairs eglandular similar to those at distal portion of the petioles; veins furcate reaching or not the laminae margin. Sori on veins, forming several lines along the segments; spores dark brown, proximal surface with coalescent ridges, mainly near trilete aperture, distal surface strongly tuberculate, 59.3−60.0 μm diam. Distribution and ecology: Jamesonia rufescens occurs in Bolivia, Brazil, Colombia, Ecuador, Peru, and Venezuela, at 2000-3600 m elevation (Tryon 1970 Jamesonia rufescens is recognized by its pinnate-pinnatisect to pinnate-pinnatifid, triangular or sometimes ovate lamina, triangular to ovate pinnae, moderately to densely covered by hairs, the hairs eglandular, brown to hyaline, sometimes bicolorous, erect to slightly tortuous, apical cell elongated with apex rounded, straight rachises, ovate ultimate segments, with several superficial lobes, and crenate margins. Tryon (1970) selected the published illustration to be the lectotype of Gymnogramma rufescens. However, the original material was located at Paris Herbarium and according to the Article 9.12 of the International Code of Nomenclature for Algae, Fungi, and Plants (Turland et al. 2018), in the designation of a lectotype, specimens have priority over illustrations. So, the original material at P herbarium was chosen as the lectotype. Tryon (1970) did not mention the presence of this species in Brazil. Only Windisch (1984) published a paper that presented its occurrence. He discussed the similarity of the plant collected by Capell s.n. (FCAB 0273), in the Pico da Caledônia, with Jamesonia rufescens described by Tryon (1970). Windisch (1984) concluded that it is another case of disjunction between species occurring in the Andes and in high regions of the southeastern of Brazil.
The Brazilian plants present only eglandular hairs on the rhizomes, petioles, rachises, and laminae, whereas a analyzed plant from Bolivia (J.C. Solomon 16157, MBM, MO) shows glandular hairs on the petioles, rachises, and laminae. It suggests that the Brazilian plants can be a distinct species, but more studies are necessaries to confirm this assumption.
Based on the key of Eriosorus by Tryon (1970), the putative name for this specimen is Jamesonia congesta (Christ) Christenh., which resembles the studied specimen by the hairs and bristles of the rhizome, and the shape and division of the lamina (narrowly triangular to narrowly ovate, 2-pinnate-pinnatisect). However, J. congesta presents rachis and both surfaces of lamina densely covered by glandular and eglandular hairs (vs. rachises and both surfaces of the lamina sparsely to moderately covered by only eglandular hairs).

Author's Contributions
Aline Possamai Della: substantial contribution to the concept and design of the study, contribution to data collection, contribution to data analysis and interpretation, and contribution to manuscript preparation.
Jefferson Prado: substantial contribution to the concept and design of the study, contribution to data analysis and interpretation, contribution to manuscript preparation, and contribution to critical revision, adding intellectual content.