Adiantum pyramidale (L.) Willd.

Authority

Proctor, George R. 1989. Ferns of Puerto Rico and the Virgin Islands. Mem. New York Bot. Gard. 53: 1-389.

Family

Pteridaceae

Scientific Name

Adiantum pyramidale (L.) Willd.

Description

Species Description - Rhizome creeping, subwoody, 4-9 mm thick (excluding scales and stipe bases), clothed toward apex with light yellowish-brown, lustrous, subclathrate, narrowly deltate-attenuate scales 2.5-6 mm long, the tips long-acuminate to filiform. Fronds closely distichous, erect-spreading, 25-85 (-100) cm long; stipes dull purple-brown to blackish, shorter to longer than the blades, 9-48 cm long, 1-3.5 mm in diam., muriculate, and sparsely clothed with deciduous, lax, yellowish-brown, hairlike scales chieffy toward base. Blades lance-oblong to broadly deltate-ovate or subpentagonal, 20-40(-45) cm long, 20-42 cm broad, 2-pinnate except at base, the lowest pair of pinnae unequally forked or with one or more pairs of pinnate pinnules (both acroscopic and basiscopic pinnate pinnules maybe present); rhachis and costae densely pubemlous throughout chiefly on abaxial side, and also with a few scattered longer, flexuous, pluricellular hairs; pinnae 2-11 pairs and a similar or shorter terminal one, altemate, distant, oblique, linear-attenuate; pinnules rhombic-oblong to rhombic-ovate, mostly 9-21 mm long, 4-7 mm broad, dimidiate, broadly cuneate or rectangular at base, short-stalked, the sterile ones more or less acuminate, subfalcate, with margins obscurely dentate-serrulate to subentire, the fertile ones rounded-obtuse or somewhat acute at the apex (rarely acuminate); tissue dull dark green, rigidly herbaceous or subcoriaceous, striate and often somewhat harsh in texture. Sori oval to oblong, nearly straight or slightly curved, up to nine per pinnule, bome chieffy along the acroscopic margin and around the apex, rarely a few on basiscopic side; indusioid flap light to dark brown with pale, erose margin.

Discussion

Basionym. Polypodium pyramidale Linnaeus, Sp. pL2: 1093. 1753.

Type. Petiver, Pter, Amer,, t. 4, fig. 2, copied from Plumier, Traite foug. Amer., /. 54, based on a plant from Grand Cul-de-sac, nr. Leogane, Haiti. Plumier's t. 53 and /. 97 also represent diflferent forms ofthe same species, which is highly polymorphic.

Syn. Adiantum cristatum Linnaeus, Syst. nat. ed. 10, 2: 1328. 1759. (Lectotype. Plumier, Descr. pl. Amer., t. 46 (=Traite foug. Amer., t. 97), based on a plant from Hispaniola.)

Adiantum crenatum Willdenow in Linnaeus, Sp. pl. 5: 446. 1810. (Lectotype. Plumier, Traite foug. Amer,, t. 53, based on plants found in Hispaniola and Martinique)

Adiantum quadriternatum Desvaux, Ges. Naturf Freunde Berlin Mag. 5: 327, 1811, [No type cited; Desvaux later (Mem, Soc, Linn, Paris 6: 309. 1827) synonymized this name under A. crenatum Willdenow.]

Adiantum microphyllum Kaulfuss, Enum. filic. 204. 1824. (Type. Poeppig s.n., from Cuba, not seen; Kaulfuss also cited Schkuhr, Krypt. Gew., t. 118, as "optima.")

Adiantum nigrescens Fee, Mem. foug. 5:117.1852; 7: 28, t. II, fig 2. 1857. (Type. L'Epagnier, from Port-au-Prince, Haiti, RB.)

Adiantum striatum of Jenman, Fems Brit. W . Ind. 93. 1899 (incl. vars. a, b, c, & d), not Swartz, 1788.

Distribution and Ecology: General Distribution. Greater and Lesser Antilles. Distribution in Puerto Rico. Of wide occurrence in both lowland and mountainous areas, but apparently lacking from eastem end of the island; recorded from Adjuntas, Aguas Buenas, Arecibo, Barranquitas, Bayamon, Cayey, Coamo, Guayanilla, Guaynabo, Gurabo, Isabela, Mayagiiez, Naranjito, Quebradillas, Toa Baja, Utuado, Vega Alta, Yabucoa, and Yauco; to be expected in many more areas. Virgin Islands. St. Thomas. Habitat. Shaded rocky banks and wooded hillsides at low to rather high elevations (sea-level-940 m), common. This species appears to grow equally well in calcareous and non-calcareous areas, but usually grows in soil or humus and not in direct contact with rocks. The closely related A. melanoleucum, on the other hand, almost always grows in direct contact with rocks, the rock always being limestone.

Distribution

General Distribution. Greater and Lesser Antilles. Distribution in Puerto Rico. Of wide occurrence in both lowland and mountainous areas, but apparently lacking from eastem end of the island; recorded from Adjuntas, Aguas Buenas, Arecibo, Barranquitas, Bayamon, Cayey, Coamo, Guayanilla, Guaynabo, Gurabo, Isabela, Mayagiiez, Naranjito, Quebradillas, Toa Baja, Utuado, Vega Alta, Yabucoa, and Yauco; to be expected in many more areas. Virgin Islands. St. Thomas.

West Indies| Puerto Rico South America| Aguas Buenas Puerto Rico South America| Adjuntas Puerto Rico South America| Arecibo Puerto Rico South America| Barranquitas Puerto Rico South America| Bayamón Puerto Rico South America| Cayey Puerto Rico South America| Coamo Puerto Rico South America| Guaynabo Puerto Rico South America| Gurabo Puerto Rico South America| Isabela Puerto Rico South America| Naranjito Puerto Rico South America| Quebradillas Puerto Rico South America| Toa Baja Puerto Rico South America| Utuado Puerto Rico South America| Vega Alta Puerto Rico South America| Yabucoa Puerto Rico South America| Yauco Puerto Rico South America| Virgin Islands South America| Saint Thomas Virgin Islands of the United States South America|