TREATMENT FROM THE JEPSON MANUAL (1993) |
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©Copyright 1993 by the Regents of the University of California
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Plant in soil; rhizome hairy, less often scaly, sometimes from bud near petiole base
Leaves alike; petiole strongly grooved on upper side, glabrous or hairy, rarely scaly, in X -section vascular strands 1many in U shape; blade generally 15- or more pinnate; axes, blades glabrous or hairy, rarely scaly; veins pinnate from midrib, generally forked beyond, free except sometimes at margin of fertile segments
Sporangia at or near margin, generally ± covered by reflexed segment margins (false indusia); true indusium 0, or linear, purse-shaped, opening toward margin or fused with it to form cup; stalk cells in 13 rows; spores spheric or elliptic, scar of 3 radiating branches or linear
Genera in family: ± 17 genera, ± 375 species: especially tropical. Variously defined; Pteridium sometimes in its own family.
Rhizome generally deep, long-creeping, branched; scales 0
Leaf: petiole near base blackish, with dense brownish hairs, above straw-colored, ± glabrous; blade 24-pinnate, lower surface generally hairy; 1° leaflets sometimes with nectaries in axils; veins free except at margin of fertile segments
Sporangia marginal, generally continuous except at sinuses; tips, on connecting veins, ± covered by false indusium (sterile segment margins similarly modified); true indusium inconspicuous or 0; spores spheric
Species in genus: ± 5 species: temp, tropical
Etymology: (Greek: small Pteris , fern)
Reference: [Tryon 1941 Contr Gray Herb 134:131, 3767]
Often considered (e.g., by Tryon) a single, ± worldwide, highly variable sp., but especially in tropical, subtropical, species seem distinct.