Dicranopteris spissa (Fée) L.V. Lima & Salino, comb. nov. (Figure 1–2)

Mertensia spissa Fée (1869: 200).

Type:— BRAZIL. Rio de Janeiro. Nova Friburgo. Macaé de Cima. Glaziou 2468 (lectotype designated by Lima & Salino 2018, P [P00633241] photo!, isolectotypes P [P00633243], [P00623242] photos!).

Plants terrestrial or epipetric. Rhizomes 1.5–5.20 mm thick, with reddish-brown rigid simple or branched hairs, glabrescent to tomentose. Fronds scrambling, 2–4–(6)-forked; ultimate branches 12.5–30.5 cm × 2.8–5.5 cm, lanceolate, apex pinnatifid, base asymmetric, inner side with reduced segments, external side with conform segments; ultimate segments linear 3–16 cm × 2–2.5 cm, margins revolute; abaxial surface green or pruinose; pubescent, rarely glabrescent, with reddish, rarely whitish, multicellular hairs, on the segments midrib, bacilliform glandular hairs on the midrib, secondary veins and laminar tissue. Buds covered by reddish multicellular hairs; pseudostipule present, accessory branches simple to pinnatisect. Veins 3–4-forked. Sori median, with paraphyses, spores tetrahedral.

Distribution and habitat:— Dicranopteris spissa is endemic to southeastern Brazil, occurring usually on edges of high montane forests of the south part of the Espinhaço Range, and Serra de Ibitipoca in Minas Gerais state as well as in the Serra do Mar in the states of Rio de Janeiro and São Paulo, between 900 – 1800 m (Fig. 2). In contrast, D. rufinervis has a distribution restricted to the mountains of the Espinhaço range in the north of Minas Gerais and Bahia, between 600 – 1500 m.

Notes:— Dicranopteris spissa is morphologically related to D. rufinervis and it is mainly differentiated from that species by the following characters. Accessions of D. spissa have sparse pale-yellow to reddish hairs occurring only at the base of the segment on midrib (Fig. 1 D-G) versus red hairs densely spread through the segment’s midrib in D. rufinervis (Fig. 3 C-E). Secondary veins usually are deeply immersed at the laminar tissue with bacilliform glandular hairs versus secondary veins usually not sunk in the laminar tissue, usually with sparse red hairs in D. rufinervis. Finally, the rachis is glabrescent in D. spissa but pubescent in D. rufinervis.

Conservation status:— Dicranopteris spissa and D. rufinervis are endemic to Brazil. Both species were categorized as endangered species according to IUCN Red List criteria. However, the records of the two species may be subsampled due to their resemblance with D. flexuosa, the most widely distributed species of the genus in Brazil. In contrast to the later, these two species do not occur in anthropogenic habitats and thus they are more sensible to environmental change. They occur in highland formations, usually near rock outcrops or in forest edges.

Specimens examined: — BRAZIL. Minas Gerais: Lima Duarte, Parque Estadual de Ibitipoca, 21º42’33”S 43º53’38”W, 1300m, 7 February 2017, Lima et al. 213 (BHCB, CESJ); Lima Duarte, Parque Estadual de Ibitipoca, 21º40’18”S 43º52’22”W, 1484m, 22 June 2007, Almeida et al. 1221 (BHCB); Catas Altas, Parque Natural do Caraça, 20º06’31”S 4327’31”W, 1800m, 19 May 2001, Salino et al. 6835 (BHCB); Catas Altas, Parque Natural do Caraça, 20º05’44”S 43º29’03”W, 1349m, 13 October 2016, Lima 199 (BHCB); Catas Altas, Parque Natural do Caraça, 20º05’44”S 43º29’03”W, 1349m, Lima 200 (BHCB); Catas Altas, Parque Natural do Caraça, 07 October 2000, Salino 5755 (BHCB); São Gonçalo do Rio Preto, Parque Estadual do Rio Preto, 18°12’53”S 43º20’06”W, 1600-1700m, 07 August 2003, Salino et al. 9350 (BHCB); São Gonçalo do Rio Preto, Parque Estadual do Rio Preto, 19 October 2000, Salino 5801 (BHCB); Itamarandiba, Parque Estadual da Serra Negra, 18º00’55”S 42º45’14”W, 1570-1600m, 04 July 2006, Salino et al. 10899 (BHCB); Felício dos Santos, 18º 12’37”S 43º17’05”W, 1150-1350m, 31 October 2004, Salino et al. 90406 (BHCB); Santo Antônio do Itambé, Parque Estadual do Pico do Itambé, 18º24’05”S 43º18’57”W, 1357m, 07 October 2006, Almeida et al. 596 (BHCB). Rio de Janeiro: Nova Friburgo, Macaé de Cima, Glaziou 4456 (RB); Rio de Janeiro, Parque Nacional da Tijuca, Pico da Tijuca, 14 June 1933, Brade 12555 (RB); Santa Maria Madalena, Serra da Forquilha, 4 February 1935, Brade 14354 (RB);. São Paulo: Natividade da Serra, Parque Estadual da Serra do Mar, núcleo Santa Virgínia, 23º26’56”S 45º11’35”W, 900-1150m, 01 November 2001, Salino et al. 7830 (BHCB); Ubatuba, Parque Estadual da Serra do Mar, Núcleo de Picinguaba, Trilha do Pico do Cuscuzeiro, próximo ao marco da divisa entre Rio de Janeiro e São Paulo, 23°21’33.7”S, 44°50’53.0”W, 07 August 2001, Salino et al. 7317 (BHCB).