Blechnum gracile Kaulfuss (1824: 158)

Dittrich, Vinícius Antonio De Oliveira, Salino, Alexandre & Monteiro, Reinaldo, 2015, The Blechnum occidentale (Blechnaceae, Polypodiopsida) species group in southern and southeastern Brazil, Phytotaxa 231 (3), pp. 201-229 : 211-213

5. Blechnum gracile Kaulfuss (1824: 158) . Fig. 3A–C

Type:— BRAZIL. Without date, Otto s.n. (holotype B).

Blechnum diplotaxicum Fée (1869: 25) . Type:— BRAZIL. Rio de Janeiro: Alto Macahé, 19 May 1868, A.F.M. Glaziou 2303 (holotype P00338297, isotypes K000954369, P00338296, S14-3971, BR0000006960018).

Blechnum subdimorphum Copeland (1941: 288) . Type:— MEXICO. Veracruz: Córdoba, 800m, 31 January 1938, E.B. Copeland 50 (holotype MICH, isotypes B200034239, BM, P00627645, UC600170).

Plants terrestrial or epipetric; rhizomes erect to ascending, stoloniferous, the scales narrowly triangular, dark tan, concolorous, margins entire, with sparse glandular hairs; fronds monomorphic, 19.8–40.8 cm long; stipes 4.7–15.9 cm long, 1.0– 1.2 mm diam., paleaceous, the base with dark to light tan scales, concolorous, the margin irregularly toothed with glandular hairs; blade 15.1–24.9 × 8.1–15.4 cm, ovate or deltoid, membranaceous to papyraceous, pinnate, abruptly reduced on apex to a conform pinna 1.6–2.1 times longer than the lateral pinnae, truncate at base; rachis glabrescent on both surfaces; pinnae 3–5(–8) pairs, 5.4–11.7 × 1.0– 1.1 cm, ascending or rarely patent (basal ones), linear-lanceolate to narrowly elliptic, slightly falcate or not falcate, petiolulate (basal ones) to fully or partially adnate to the rachis (apical ones); veins free or rarely forming one or another costal areola, 1–2-bifurcate, with clavate ends just before the margin.

Distribution and habitat: — Brazil (Goiás [first record for central-west Brazil], Minas Gerais, Espírito Santo, Rio de Janeiro, São Paulo, Paraná, Santa Catarina, and Rio Grande do Sul); furthermore Mexico, Guatemala, Belize, Honduras, El Salvador, Nicaragua, Costa Rica, Panama, Greater Antilles, Colombia, Venezuela, Trinidad & Tobago, Guyana, Suriname, French Guiana, Ecuador, Peru, Bolivia, Paraguay, and Argentina. A common species in Brazil, not locally endangered. Individuals of this species usually occur on the banks of streams in relatively well-illuminated areas, between 110 and 1150 m in the study area.

Comments: —The name Blechnum gracile is adopted here instead of Blechnum fraxineum Willdenow (1810: 413) . According to Mickel & Beitel (1988), the type of Blechnum fraxineum corresponds to plants that match morphologically the triploid hybrid between Blechnum longifolium Cavanilles (1802: 263) and Blechnum occidentale . Therefore, Blechnum fraxineum is not the same as Blechnum gracile , despite the fact that Brazilian plants were frequently identified as such in checklists (e.g. Salino & Joly 2001, Mynssen & Windisch 2004, Figueiredo & Salino 2005) and herbaria. Walker (1985), in a careful study, has demonstrated that there are two cytotypes of “ Blechnum fraxineum ”. Based on the scant amount of cytologically investigated material, the author states that there seems to be a tendency of the fronds of the tetraploid to be narrower and have more pinnae (about three pairs at the base of the otherwise pinnatisect to pinnatifid lamina) than those of the diploid (one or two pairs). Furthermore, there is a tendency of the rachis and stipes of the diploid taxon to have a more pronounced red color when compared to those of the tetraploid. Mickel & Beitel (1988) have shown that the diploid cytotype has identical sterile and fertile fronds, whereas the tetraploid cytotype has slightly narrower fertile fronds than the sterile ones; the tetraploids have apical pinnae identical to the lateral ones, whereas the diploids have much smaller lateral pinnae and these often have a rounded shape and, finally, the terminal pinnae of the diploid cytotype has a cuneate base while the base of the tetraploid is subcordate with lobes present below it. As the plants from the study area are similar to the phenotype observed for the tetraploids regarding all these characteristics, we preferred to adopt the name Blechnum gracile Kaulf. in this work, although there is the need for karyological studies to determine with confidence the correct name of this taxon.

Selected specimens examined: — BRAZIL. Minas Gerais: Aiuruoca, Rio Aiuruoca , 13 March 1989, A. Salino 663 ( UEC) ; Alto Caparaó, Parque Nacional do Caparaó, caminho para a Macieira , 29 April 1989, A. Salino et al. s.n. ( UEC) ; Barbacena, futuro Distrito Industrial de Barbacena , 21°13’15,64”S, 43°44’36,24”W, ca. 1180 m, 09 December 2002, V.A.O. Dittrich & A. Salino 1257 ( HRCB) ; Brazópolis, Cascatinha , without date, without collector ( OUPR 5384 ) ; Caldas, Serra dos Poços , ca. 1, 5 km de Pocinhos do Rio Verde , ca. 21°56’S, 46°23’W, ca. 1150–1200 m, 16 June 1995, M.R. Pietrobom-Silva 1921 ( MBM, SJRP) ; Camanducaia, mata do trevo de acesso a Camanducaia , 22°44’53”S, 46°09’17”W, 1180 m, 01 June 2001, A. Salino 6898 ( BHCB) ; Conceição do Mato Dentro , 03 December 1989, R.F. Novelino 638 ( CESJ) ; Divino, Fazenda Barra São Pedro , 02 April 1989, L.S. Leoni & A.M. Leoni 746 ( GFJP) ; Itabirito, área da Serra da Moeda , 20°19’10”S, 43°56’17”W, 1450 m, 14 June 2001, A. Salino et al. 7066 ( BHCB) ; Jaboticatubas, Rod. MG-2, Campo Redondo , 08 August 1972, G.G. Hatschbach 30080 ( MBM, PACA) ; Mariana, Serra do Frazão, na estrada Mariana-Santa Bárbara , 25 August 2000, A. Salino 5667 ( BHCB) ; Nova Lima , Estação Ecológica de Catarina, 20°04’10”S, 44°00’07”W, 08 November 2001, L.C.R.S. Teixeira et al. 27 ( BHCB) ; Ouro Preto, Saramenha , without date, L. Damazio s.n. ( OUPR 10135 ) ; Poços de Caldas, Retiro Branco , 24 August 1988, J.T. Motta 1332 ( MBM) ; Santa Rita de Jacutinga , 25 July 1970, L. Krieger s.n. ( CESJ 9001 ) ; São João del Rei , October 1969, L. Krieger s.n. ( CESJ 7192 ) ; São Tomé das Letras, cachoeira Eubiose , 09 September 1988, E.D. Castellani 15 ( SJRP) ; Sapucaí Mirim, Bairro Santa Luzia, Serra de Campestre , 30 July 1988, A. Salino 497 ( BHCB, UEC). Espírito Santo: Castelo , Parque Estadual de Forno Grande , 20°31’10”S, 41°05’14”W, 1250 m, 26 June 2008, A. Salino et al. 13661 ( BHCB) ; Santa Teresa, Estação Biológica de Santa Lúcia, margem do Rio Timbuí , 24 February 1996, A. Salino 2587 ( BHCB). Rio de Janeiro: Itatiaia , Lago Azul , 800 m, September 1933, A.C. Brade 12378 ( RB) ; Petrópolis, Vale Bonsucesso, caixa d’água, ca. 720 m, 06 May 1972, D. Sucre & T.R. Soderstrom 9110 ( RB). Unknown municipality: Serra dos Órgãos, 1837, G. Gardner 184 ( FI). São Paulo: Analândia, Serra do Cuscuzeiro , ca. 22°08’S, 47°40’W, 27–29 November 1987, A. Salino 196 ( SJRP, UEC) ; Brotas, Fazenda Santa Elisa, margem do rio Jacaré-pepira , ca. 470 m, VIII.1991, A. Salino 1006 ( UEC) ; Espírito Santo do Pinhal, Fazenda Palmeiras, na rodovia para São João da Boa Vista , ca. 870 m, 29 December 1987, A. Salino 261 ( UEC) ; Iguape, Serra de Paranapiacaba, Rio Temível , November 1925, A.C. Brade 8410 ( HB) ; Itirapina, Serra do Itaqueri, margem do rio da Cachoeira , ca. 770 m, 23 July 1991, A. Salino 992 ( BHCB, UEC) ; Natividade da Serra, Parque Estadual da Serra do Mar, núcleo de Santa Virgínia , base de Vargem Grande , trilha para a Cachoeira da Boneca , Ribeirão Grande , 23°25’57”S, 45°12’36”W, ca. 800 m, 10 August 2001, A. Salino et al. 7458 ( BHCB) ; Pirassununga, Morro da Senzala , 750 m, 31 December 1987, A. Salino 262 ( BHCB, UEC) ; São Carlos, rodovia vicinal de acesso ao Broa , ca. 13 km de São Carlos, 26 September 1997, M.R. Pietrobom-Silva 4183 ( SJRP) ; São Paulo, próximo a Jaraguá , 03 March 1942, W. Hoehne 1029 ( CESJ, MBM, SJRP, SPF) ; Sete Barras, Parque Estadual Intervales, Base de Saibadela , Rio Saibadela , 24°12’– 24°15’S, 48°03’– 48°06’W, 110 m, 13 November 2001, V.A.O. Dittrich 995 ( HRCB) ; Ubatuba, Parque Estadual da Serra do Mar, núcleo Picinguaba , trilha do Jatobá , 23°20’26”S, 44°50’13”W, 40 m, 02 May 2001, A. Salino et al. 6674 ( BHCB). Paraná: Bocaiúva do Sul, Sesmaria, rio Capivari , 24 March 1970, G.G. Hatschbach 24045 ( MBM, PACA) ; Dois Vizinhos, Rio Chopim , próximo a barra, 11 June 1968, G.G. Hatschbach & O. Guimarães 19377 ( HB, HBR, MBM, PACA) ; Guaratuba, Rio Arraial, Fazenda Bamerindus , 01 January 1996, J.M. Silva & J. Saldanha 1779 ( MBM) ; Morretes, Rio Mãe Catira , 100–200 m, 07 August 1968, G.G. Hatschbach 19561 ( MBM, PACA) ; Reserva, Rio Imbaú , 11 December 1996, F. Chagas e Silva & E.M. Francisco 2177 ( RB) ; Três Barras do Paraná, Canyon do Rio Guarani, 22 February 1993, M.C.M. Marques s.n. ( BHCB 30146 ). Santa Catarina: Araranguá , Morro da Moça , 12 March 1942, R. Reitz 876 ( PACA). Rio Grande do Sul: Derrubadas , Parque Estadual do Turvo , 08 July 1982, R.M. Bueno 35, 39 ( ICN). Prope Santo Ângelo , without date, J. Dutra 147 ( ICN). Goiás: Goianápolis , Parque Estadual Altamiro de Moura Pacheco , Trilha da Onça , 16°32’07”S 49°06’48”W, 01 April 2005, M.L. Fonseca 5773 ( RB, photo) .

Figures

FIGURE 3. A–C. Blechnum gracile. A. Habit. B. Part of a pinna showing venation. C. Rhizome scale. D–F. Blechnum heringeri. D. Habit. E. Part of a pinna showing venation. F. Rhizome scale. (A–C from L. Krieger s.n., CESJ50219; D–F from E.P. Heringer s.n., CESJ61864).