1. Deparia acrostichoides (Sw.) M. Kato (silvery spleenwort,
silvery glade fern) Pl. 4a,b; Map 19
Athyrium thelypterioides (Michx.) Desv.
Diplazium acrostichoides (Sw.) Butters
Rhizomes prostrate, short-creeping. Rhizome scales concolorous, light brown,
lanceolate. Leaves monomorphic, 40–110 cm long. Petioles shorter than the leaf
blade, with scattered, light brown scales and multicellular hairs, the bases
with 2 vascular bundles. Rachises with multicellular hairs, sometimes also
sparsely scaly. Leaf blades lanceolate to elliptic in outline, 1 time pinnately
compound. Pinnae 2–14 cm long, lanceolate to linear, the tips attenuate, deeply
pinnately lobed, the margins entire or shallowly toothed. Veins not
anastomosing. Sori linear. Indusia attached laterally, arching over the sori.
Spores 64 per sporangium, monolete, 25–50 mm long, brown. 2n=80. June–September.
Widely scattered through the eastern half of the state (eastern U.S. and adjacent Canada
west to Kansas).
Mesic forests in the bottoms of ravines and sinkholes, and in the valleys of
streams, on a variety of substrate types.