Athyrium

Roth

Tent. Fl. Germ. 3(1,1): 31, 58. 1799.

Common names: Lady fern
Etymology: Greek athyros, doorless the sporangia only tardily push back the outer edge of the indusium
Treatment appears in FNA Volume 2.

Plants generally terrestrial. Stems short-creeping or ascending, stolons absent. Leaves monomorphic, usually dying back in winter. Petiole ± 0.5 times length of blade or less, base swollen and dentate, persisting as trophopod over winter or not; vascular-bundles 2, lateral, lunate in cross-section. Blade lanceolate to elliptic or oblanceolate, 1–3-pinnate-pinnatifid, gradually reduced distally to confluent, pinnatifid apex, herbaceous. Pinnae not articulate to rachis, segment margins serrulate or crenate; proximal pinnae often reduced, sessile to short-petiolulate, ± equilateral; costae adaxially grooved, grooves continuous from rachis to costae to costules; indument absent or of linear to lanceolate scales or 1-celled glands abaxially. Veins free, simple or forked. Sori in 1 row between midrib and margin, round to elongate, straight or hooked at distal end, or horseshoe-shaped; indusia shaped like sori, persistent, attached laterally or with narrow sinus, or indusia absent. Spores brownish, rugose. x = 40.

Discussion

In species outside the flora stems are sometimes long-creeping to erect, with leaves radially or dorsiventrally arranged.

Species about 180 (2 in the flora).

Key

1 Sori round, submarginal; indusia much reduced or usually absent. Athyrium distentifolium var. americanum
1 Sori elongate or hooked, medial; indusia well developed. Athyrium filix-femina
... more about "Athyrium"
Masahiro Kato +
persisting +
swollen +
simple to commonly +
1-3-pinnate-pinnatifid;lanceolate;elliptic or oblanceolate +
reduced +
roundish +
Lady fern +
Worldwide +
Greek athyros, doorless +  and the sporangia only tardily push back the outer edge of the indusium +
often +  and glabrous +
monomorphic +
0.5 times length of blade;0.5 times length of blade +
not articulate +
sessile +  and short-petiolulate +
Tent. Fl. Germ. +
round +, cuplike +, hoodlike +, reniform +, falcate +  and linear +
johnson1986c +, kato1977a +  and liew1972a +
2 (?) +  and 3 (?) +
persistent +
linear;lanceolate +
crenate +  and serrulate +
straight +
persistent +
with narrow sinus +  and attached +
discrete +
indusia--shaped +, horseshoe--shaped +, hooked +, round +  and elongate +
reniform +  and oblong +
dictyostelic +, unbranched +  and branched +
ascending +  and short-creeping +
Athyrium +
Dryopteridaceae +
epiphytic +  and hemiepiphytic +