4.
Nephrolepis cordifolia
(Linnaeus) C. Presl, Tent. Pterid. 79. 1836.
Tuberous sword fern, tuber sword fern
Polypodium cordifolium
Linnaeus, Sp. Pl. 2: 1089. 1753;
Aspidium cordifolium
(Linnaeus) Swartz
Stem scales spreading, concolored. Tubers present or absent. Leaves 2.5--10.7 × 0.3--0.7 dm. Petiole 0.3--2 dm, moderately to densely scaly; scales spreading, pale brown throughout. Blade lacking scales, glabrous (rarely with a few branched hairs abaxially). Rachis 2.2--9 dm, points of pinna attachment 5--12 mm apart; scales moderately spaced to dense, pale to dark brown, point of attachment distinctly darker. Central pinnae oblong to lanceolate-oblong, straight to slightly falcate, 0.9--5 × 0.4--0.9 cm, base auriculate-cordate, acroscopically overlapping rachis, acroscopic lobe deltate, margins entire to serrulate to smoothly crenate, apex acute to bluntly rounded; costae adaxially glabrous. Indusia reniform to lunate or deltate-rounded, attached along broad sinus, 1.1--1.7 mm wide. 2 n = 82.
Terrestrial or epiphytic in wet, shady places, limestone ledges, cliffs, rock, roadsides, and often old homesites or waste places; widely escaped from cultivation and only questionably native to any particular region; 0 m; Fla.; Mexico; West Indies; Central America; South America; Africa; se Asia; Pacific Islands in Hawaii.
