Goniopteris smithii is most similar to G. nicaraguensis (Fournier 1872: 252) Salino & Almeida (2015: 41), G. oroniensis (Gómez 1978: 9) Salino & Almeida (2015: 41), and G. tristis (Kunze 1834: 47) Brade (1972: 217) by the laminae with conform apex and proximal pinnae with cuneate base, but differs by the basal vein pair from adjacent segments united below the sinuses and scales on the abaxial side of rachises and costae.

Type:— BRAZIL. Bahia. Jussari, RPPN Serra do Teimoso, 15º09’15.8” S, 39º31’24.2” W. 260–400 m, 02 November 2002, A. Salino & J. G. Jardim 8160 (holotype BHCB!, isotype CEPEC!).

Plants terrestrial; rhizomes short-creeping bearing lanceolate, brown scales, 3.2–4.3 mm, with furcate and stellate trichomes. Leaves 59–104 cm long, monomorphic. Petioles sulcate adaxially, 25–55 cm long, 1.6–5.1 mm, with few scales at bases, hirsute with furcate and stellate trichomes 0.04 to 0.1 mm long. Laminae 33–50 cm long, obovate, chartaceous, not verrucose, 1-pinnate-pinnatifid, the apex abruptly reduced and conform with distal pair of pinnae adnate to apical pinna. Buds present at bases of distal pinnae. Rachises hirsute mainly along the grooves with furcate and stellate trichomes 0.04–0.07 mm long, also with scattered short linear-lanceolate to linear scales 0.25–1.25 mm long. Pinnae 4–9 pairs per leaf, alternate, 16.5–23.5 cm × 3.4–4.5 cm, with the basal pair shorter than median pinnae, ascending, narrowly elliptic, sessile to short-stipitate to 0.4 mm, the apices acuminate and bases cuneate; pinnae incised 2/3 their width; abaxial side lacking hairs or only with some simple hairs at the sinuses, with linear to linear-lanceolate costal scales 0.25–1.25 mm evident at costal bases, lacking scales on costules and veins; adaxial side glabrous, except for some simple and furcate hairs to 0.07 mm and some sparse reduced linear scales on costae. Segments 5.5–7.8 mm wide, slightly arcuate, entire, rounded or obtuse at tips; veins 10–15 pairs per segment, unbranched, ending in clavate tips adaxially, the basal vein pair (sometimes two pairs) from adjacent segments united below the sinuses and forming an excurrent vein, the distal one of each pair arising from the costa, rarely from the costule. Sori inframedial, indusia reniform or round-reniform, sometimes spathulate, entire, the surface with simple and furcate hairs; sporangia glabrous.

Distribution and habitat:— Goniopteris smithii is endemic to the southern Bahia state, where it grows in Atlantic rainforests usually on hillsides at 250– 400 m.

Etymology:— The epithet honors Dr. Alan R. Smith from the University of California at Berkeley (UC), an authority on Thelypteridaceae.

Additional specimens examined (paratypes):— BRAZIL. Bahia: Jussari, estrada de Jussari para Palmira, RPPN Serra do Teimoso, 15º09’37”S, 39º32’10” W, 14 February 2004, P. Fiaschi 1949 et al. (CEPEC, NY), ibidem, RPPN Serra do Teimoso, 15º09’29” S, 39º31’43”W, 09 April 1998, A. M. Amorim 2366 et al. (CEPEC, NY, UC), ibidem, 18 June 2003, A. M. Amorim 3715 et al. (CEPEC); Camacan, RPPN Serra Bonita, Fazenda Paris, Interior da Cabruca, 15º30’52”S, 39º40’27” W, 250 m, 17 June 2009, F. B. Matos 1796 (CEPEC); Camacan, estrada Camacan-Jacareci, Serra Bonita, 15º22´54” S, 39º32´57” W, 265 m, 12 December 2014, A. Salino 16032 et al. (BHCB, UC).

Notes:— Goniopteris smithii is most similar to G. nicaraguensis (Mexico to Panama), G. oroniensis (endemic to Costa Rica), and G. tristis (Costa Rica, Panama, Guianas, Colombia, Ecuador, Peru, Bolivia, and northern Brazil) by the laminae with a conform apex and proximal pinnae with long-cuneate bases, but differs by the basal vein pair from adjacent segments united below the sinuses and scales abaxially on rachises and costae. Goniopteris. nicaraguensis also differs in having proximal pinnae with short-cuneate bases, in having exindusiate sori and setulose sporangia (vs. proximal pinnae with long-cuneate bases, indusiate sori, and glabrous sporangia in G. smithii). In addition, G. nicaraguensis has dense furcate trichomes 0.1 mm long on the rachises and along costae adaxially, and rachises adaxially with stalked reddish trichomes 0.05 mm long, as well as simple or furcate trichomes 0.06–0.08 mm long on the costae and veins abaxially. Goniopteris oroniensis differs from G. smithii by the erect to suberect rhizomes, flexuose rachises, basal pinnae long-petiolulate, exindusiate sori, and setose sporangia. Goniopteris tristis differs in having simple, furcate, and stellate hairs along costae abaxially and, simple hairs on the costules and veins abaxially; it shares with G. smithii the usual presence of buds on adaxial side of the distal pinnae.

In southeastern Brazil there are two other endemic species with cuneate pinna bases: Goniopteris cuneata (Christensen 1913: 253) Brade (1972: 215) and G. monosora (Presl 1851: 36) Brade (1972: 216). However, these species have basal veins from adjacent segments meeting the sinuses, and G. cuneata usually has 7–15 pinna pairs, simple and furcate hairs along costae, costules, and veins abaxially, and simple hairs on abaxial surfaces between the veins, furcate or simple hairs on sporangial stalks, and costal scales are absent. Goniopteris monosora usually has 10– 23 pinna pairs, simple and furcate hairs along costae, costules, and veins abaxially, and simple hairs on abaxial surfaces between the veins (such hairs sometimes absent), indusia with only simple hairs, and simple hairs on sporangial stalks.