Pteridium aquilinum (L.) Kuhn
Descripción
Fronds 0.5–1 m long; rachises slightly to strongly pubescent; blades lacking free lobes between segments; penultimate axes pubescent abaxially with white hairs, scattered, clear brown, straight hairs 1–1.5 mm long, adaxially with short, white hairs, red-tipped, glandular hairs confined to medial grooves; costae terete abaxially; laminar surfaces abaxially between costae and segment margins pubescent to glabrous on veins, adaxially with scattered to rare hairs only along reflexed margins, hairs 0.5–0.8 mm long, white; false indusia 0.2–0.8 mm wide with erose margins, with scattered to numerous long cilia, or glabrous.A
Forma de vida
TerrestreA
Elevación
0 – 3300 mA
Ecología y Hábitat
In open disturbed areas.A
Categoría IUCN
No incluidaB
Categoría NOM-059-SEMARNAT-2010
No incluidaC
Discusión taxonómica
Distinct by the penultimate axes with lax white hairs, often also with scattered straight clear brown hairs.
Key to the Mexican Varieties of Pteridium aquilinum
Abaxial laminar surfaces glabrous, the hairs limited to the midveins and margins (but not the indusia)..............................................................................................................var. latiusculum
Abaxial laminar surfaces with hairs on the veins as well as on the midveins and margins, abaxial hairs tortuous to curved, often obscuring the laminar surfaces; sterile indusia 0.4 mm or more wide; most of Mexico other than Baja California and the northern tier of states............................................var. feei
Pteridium aquilinum var. feei (W.Schaffn.) Maxon, Publ. Field Mus. Nat. Hist., Bot. Ser. 17: 308. 1938
Pteris feei W.Schaffn. ex Fée, Mém. Foug., 8. Ic. Esp. Nouv. 73. 1857
Pteridium feei (Schaffn. ex Fee) Maxon ex Faull, Contr. Arnold Arbor. 11: 87. 1938
Adaxial laminar surfaces with scattered hairs, primarily on costae and near segment margins; terminal cell of costal hairs pale, inconspicuous; abaxial costae with lax pale hairs, also with frequent clear brown stiff hairs; segments with abundant, long, tangled hairs 0.6–1 mm long, often obscuring the laminar surfaces, also evident from curved adaxial margins and margins of indusia; indusia 0.4 mm or more wide.
Distribution. Open, disturbed areas at higher elevations; 1800–3050 m. Mexico; Guat, Hond, Salv.
Selected Specimens Examined. Ags (McVaugh 18453, MEXU, MICH). Chis (Ghiesbreght 224, NY). Coah (Riskind et al. 1719, LL). DF (Ventura A. 1428, NY). Dgo (Fisher s.n., 13 Aug 1937, NY). Gro (Hamilton & Rowell 3218, NY). Gto (Galván 2498, IEB). Hgo (Rose 9204, NY). Jal (Puga & Carvajal H. 10172, ENCB). Méx (Dunn & Dunn 18881, NY). Mich (King & Soderstrom 4742, NY). Mor (Lyonnet 2417, US). Nay (Norris & Taranto 14536, MICH). NL (Rodríguez L. 95, NY). Oax (Mickel 1392, NY). Pue (Ventura A. 1260, NY). Qro (Zamudio 2674, IEB). Sin (González Ortega 4079, MEXU). SLP (Mickel 557, NY). Ver (Nee & Taylor 26764, NY).
Unverified, Doubtful, or Mistaken Reports. Tab (reported by Magaña, 1992, but figured plant appears to be P. caudatum). Pteridium aquilinum var. feei is distinguished by lamina abaxially with tortuous or curved hairs, indusia broad and ciliate, laminar hairs 1–1.5 mm long, straight, clear, brown.
Pteridium aquilinum var. latiusculum (Desv.) Underw. ex A.Heller, Cat. N. Amer. Pl. (ed. 3) 17. 1909
Pteris latiuscula Desv., Mém. Soc. Linn. Paris 6(3): 303. 1827
Pteridium latiusculum Hieron., Wiss. Ergebn. Schwed. Rhodesia-Kongo-Exped. 1911-1912 1: 7. 1914
Adaxial laminar surfaces with scattered hairs, primarily on costae and near segment margins; abaxial costae with lax pale hairs, axes with occasional brown hairs; segments with hairs on costae and on curved adaxial margins but glabrous between costae and margins; indusial margins glabrous; 2n=104 (USA).
Distribution. Dry to moist pine-oak forests; 2000–2650 m. Canada, e USA, w to e slope of Rocky Mts; Mexico; Europe, Asia.
Selected Specimens Examined. Chih (Knobloch 78, MEXU; Palmer 288, NY). Coah (Wendt & Adamcewicz 501, TEX). Dgo (González 1530, MEXU; Maysilles 7748, NY). NL (Hinton 22135, TEX; Mueller & Mueller 366, TEX, MEXU). Sin (Dunn et al. 21801, NY; Johnston et al. 11441, NY). Son (Phillips 418, US).
Most reports of var. pubescens (Synonym of Pteridium pubescens) from Mexico are var. latiusculum. Var. latiusculum is distinct from var. pubescens in having glabrous abaxial laminar surfaces except for hairs on the costae and segment margins (but not on indusia). Var. pubescens is distinct from var. latiusculum in its abaxial surfaces densely pubescent between margins and costae vs. only on costae, and the indusia ciliate to pubescent vs. glabrous. It varies from glabrous to sparsely hairy on the laminar tissue abaxially. Var. pubescens, with its straight hairs scattered on the abaxial surfaces, is limited to the Baja California peninsula and extends northward along the coast to Alaska, extending inland across Canada to northern Michigan and widespread in the western United States. Var. latiusculum, besides occurring in eastern North America, is found in the eastern Rockies and also in Arizona and New Mexico. As Tryon (1941) pointed out, in areas of sympatry var. latiusculum and var. pubescens intergrade. Jacobs and Peck (in FNA Ed. Comm., 1993) claimed that in the United States, all Pteridium west of the Great Plains is var. pubescens, and var. latiusculum occurs east of the Great Plains, but not in Mexico.A
Key to the Mexican Varieties of Pteridium aquilinum
Abaxial laminar surfaces glabrous, the hairs limited to the midveins and margins (but not the indusia)..............................................................................................................var. latiusculum
Abaxial laminar surfaces with hairs on the veins as well as on the midveins and margins, abaxial hairs tortuous to curved, often obscuring the laminar surfaces; sterile indusia 0.4 mm or more wide; most of Mexico other than Baja California and the northern tier of states............................................var. feei
Pteridium aquilinum var. feei (W.Schaffn.) Maxon, Publ. Field Mus. Nat. Hist., Bot. Ser. 17: 308. 1938
Pteris feei W.Schaffn. ex Fée, Mém. Foug., 8. Ic. Esp. Nouv. 73. 1857
Pteridium feei (Schaffn. ex Fee) Maxon ex Faull, Contr. Arnold Arbor. 11: 87. 1938
Adaxial laminar surfaces with scattered hairs, primarily on costae and near segment margins; terminal cell of costal hairs pale, inconspicuous; abaxial costae with lax pale hairs, also with frequent clear brown stiff hairs; segments with abundant, long, tangled hairs 0.6–1 mm long, often obscuring the laminar surfaces, also evident from curved adaxial margins and margins of indusia; indusia 0.4 mm or more wide.
Distribution. Open, disturbed areas at higher elevations; 1800–3050 m. Mexico; Guat, Hond, Salv.
Selected Specimens Examined. Ags (McVaugh 18453, MEXU, MICH). Chis (Ghiesbreght 224, NY). Coah (Riskind et al. 1719, LL). DF (Ventura A. 1428, NY). Dgo (Fisher s.n., 13 Aug 1937, NY). Gro (Hamilton & Rowell 3218, NY). Gto (Galván 2498, IEB). Hgo (Rose 9204, NY). Jal (Puga & Carvajal H. 10172, ENCB). Méx (Dunn & Dunn 18881, NY). Mich (King & Soderstrom 4742, NY). Mor (Lyonnet 2417, US). Nay (Norris & Taranto 14536, MICH). NL (Rodríguez L. 95, NY). Oax (Mickel 1392, NY). Pue (Ventura A. 1260, NY). Qro (Zamudio 2674, IEB). Sin (González Ortega 4079, MEXU). SLP (Mickel 557, NY). Ver (Nee & Taylor 26764, NY).
Unverified, Doubtful, or Mistaken Reports. Tab (reported by Magaña, 1992, but figured plant appears to be P. caudatum). Pteridium aquilinum var. feei is distinguished by lamina abaxially with tortuous or curved hairs, indusia broad and ciliate, laminar hairs 1–1.5 mm long, straight, clear, brown.
Pteridium aquilinum var. latiusculum (Desv.) Underw. ex A.Heller, Cat. N. Amer. Pl. (ed. 3) 17. 1909
Pteris latiuscula Desv., Mém. Soc. Linn. Paris 6(3): 303. 1827
Pteridium latiusculum Hieron., Wiss. Ergebn. Schwed. Rhodesia-Kongo-Exped. 1911-1912 1: 7. 1914
Adaxial laminar surfaces with scattered hairs, primarily on costae and near segment margins; abaxial costae with lax pale hairs, axes with occasional brown hairs; segments with hairs on costae and on curved adaxial margins but glabrous between costae and margins; indusial margins glabrous; 2n=104 (USA).
Distribution. Dry to moist pine-oak forests; 2000–2650 m. Canada, e USA, w to e slope of Rocky Mts; Mexico; Europe, Asia.
Selected Specimens Examined. Chih (Knobloch 78, MEXU; Palmer 288, NY). Coah (Wendt & Adamcewicz 501, TEX). Dgo (González 1530, MEXU; Maysilles 7748, NY). NL (Hinton 22135, TEX; Mueller & Mueller 366, TEX, MEXU). Sin (Dunn et al. 21801, NY; Johnston et al. 11441, NY). Son (Phillips 418, US).
Most reports of var. pubescens (Synonym of Pteridium pubescens) from Mexico are var. latiusculum. Var. latiusculum is distinct from var. pubescens in having glabrous abaxial laminar surfaces except for hairs on the costae and segment margins (but not on indusia). Var. pubescens is distinct from var. latiusculum in its abaxial surfaces densely pubescent between margins and costae vs. only on costae, and the indusia ciliate to pubescent vs. glabrous. It varies from glabrous to sparsely hairy on the laminar tissue abaxially. Var. pubescens, with its straight hairs scattered on the abaxial surfaces, is limited to the Baja California peninsula and extends northward along the coast to Alaska, extending inland across Canada to northern Michigan and widespread in the western United States. Var. latiusculum, besides occurring in eastern North America, is found in the eastern Rockies and also in Arizona and New Mexico. As Tryon (1941) pointed out, in areas of sympatry var. latiusculum and var. pubescens intergrade. Jacobs and Peck (in FNA Ed. Comm., 1993) claimed that in the United States, all Pteridium west of the Great Plains is var. pubescens, and var. latiusculum occurs east of the Great Plains, but not in Mexico.A