Sticherus gracilis (Mart.) Copeland (1947: 27)

Lima, Lucas Vieira & Salino, Alexandre, 2018, The fern family Gleicheniaceae (Polypodiopsida) in Brazil, Phytotaxa 358 (3), pp. 199-234 : 215-218

3.3. Sticherus gracilis (Mart.) Copeland (1947: 27) . Figs. 4J–L , 5C , 6C .

Mertensia gracilis Martius (1834: 107) . Gleichenia gracilis (Mart.) Moore (1862: 378) . Type:— BRAZIL. Minas Gerais, Martius s.n. (lectotype designated here [M-0243581] photo M!, isolectotype photo M! [M-0243582]).

Plants terrestrial. Rhizomes 3.15–5.20 mm thick, with scales dark-brown, rigid, narrow-triangular, with apex attenuate, margins short-ciliate to dentate. Fronds erect or scrambling, 1–3-forked, petiole 1.98–3.78 mm thick, ultimate branches 11.5–18.5 × 1.3–2.5 cm, linear to lanceolate, apex pinnatifid or caudate, base truncate, abaxial surface glabrous or with sparse scales on the rachis, scales light-brown, narrow-triangular, apex attenuate, base truncate, margins ciliate, segments linear 1.5–3.5 × 1.8–2.5 cm, margins slightly revolute, abaxial surface glabrous. Buds with scales similar to the rachis, pseudoestipule absent. Veins 1-forked. Sori medial, with hyaline paraphyses.

Distribution and habitat: —Endemic to Brazil (Distrito Federal, Goiás, Minas Gerais, Mato Grosso, Rio de Janeiro, São Paulo). This species occurs along roads, trails and forest edge at 500–1500 m. It is mainly distributed in the Cerrado domain, but also has populations in semi deciduous seasonal forest of the Atlantic Forrest domain.

Notes: — Sticherus gracilis differs from the other species of Sticherus by having the abaxial segment surfaces glabrescent, with only a few sparse scales on the rachises or rarely on the segment midribs. It is morphologically related to S. salinoi and differs by having segments smaller and patent to slightly ascending, and orange bud scales. Furthermore, S. gracilis is also morphologically related to Sticherus hypoleucus (Sodiro 1883: 8) Copeland (1947: 28) , a species with Andean distribution, from which it differs mainly by the bud scales, which in S. gracilis have ciliate margins, whereas in S. hypoleucus they have entire margins, and the segment distribution through the branches, which in S. gracilis are found on all axes, whereas in S. hypoleucus only the ultimate axes bear segments.

In the original description, Martius (1834) only provides the type locality as “Prov. Minarum parte australi”. We found two specimens among Martius’s collections in M, and here we chose the most complete specimen as lectotype. Both exsiccate at M have labels with information that matches the original description protologue.

Selected specimens examined: — BRAZIL. Distrito Federal: Brasília, Jardim Botânico de Brasília, APA Cabeça de Veado, 15º52’0”S, 47º51’0”W, 1100 m, 23 June 1999, Rodrigues 1330 (UB). Goiás: Ipameri, rodovia GO-213, 17º43’S, 48º08’W, 23 January 1996, Pietrobom 2330 (MBM); Pirenópolis, Serra dos Pirineus, córrego da barriguda, 06 November 2004, Delprete 9047 (RB). Minas Gerais: Santo Antônio do Itambé, Parque Estadual do Pico do Itambé, 18º24’05.9”S, 043º18’57,3”W, 1357 m, 07 October 2006, Almeida et al. 594 (BHCB); Boa Esperança, Parque Estadual da Serra da Boa Esperança, 21º00’00.5”S, 45º40’40.3W, 1050 m, 14 December 2007, Salino et al. 13023 (BHCB); Aiuruoca, Vale do Matutu, nas proximidades do riacho da Cachoeira das Fadas, 22º08’12,9”S, 44º64’49,9”W, 1300 m, 13 October 2004, Salino et al. 9836 (BHCB); Catas Altas, Parque Natural do Caraça, a caminho da Capelinha, 20º05’45,5”S, 43º28’54,1”W, 1350 m, 10 July 2004, Salino et al. 9622 (BHCB). Mato Grosso: Itiquira, rodovia MT299, encontro com a BR364, a 25 km de Itiquira, 17º12’S, 54º07’W, 600 m, 22 February 1994, Silva 1252 (SPF). Rio de Janeiro: Rio de Janeiro, Instituto Zoobotânico de Morro Azul, Córrego do IZMA, próximo ao criadouro, 08 July 1998, Santos 1030 (RB). São Paulo: Itirapina, ca. Engenheiro João Baptista Cabral Renno km 97, 22°15’60”S, 47°48’00”W, 500 m, 23 May 1993, Silva 966 (MO).

Figures

FIGURE 4. A–E. Sticherus bifidus (Krieger s.n., CESJ 10201). A. Detail of the abaxial segment surface. B. Rhizome scale. C. Bud scale. D. Rachis scale. E.Arachnoid scale of the abaxial side of the laminae. F–I. S. brevitomentosus (Forzza et al. 7225, BHCB). F. Detail of the abaxial segment surface. G. Rhizome scale. H. Bud scale. I. Rachis scale. J–L. S. gracilis (Salino 3611, BHCB). J. Detail of the abaxial segment surface. K. Rhizome scale. L. Bud scale. M–R. S. holttumii (Almeida et al. 4174, BHCB). M. Detail of the abaxial segment surface. N. Detail of the abaxial segment surface. O. Bud scale. P–Q. Rhizome scales. R. Rachis scale.

FIGURE 5. Habit. A. Sticherus bifidus. B. S. brevitomentosus. C. S. gracilis. D. S. holttumii.

FIGURE 6. Distribution of five taxa of Sticherus in Brazil. A. Sticherus bifidus. B. S. brevitomentosus and S. holttumii. C. S. gracilis. D. S. lanuginosus.