Matteuccia

	Taxon	Illustrator ⠉
	Onoclea sensibilis Matteuccia struthiopteris var. pensylvanica	John Myers John Myers

Plants terrestrial. Stems obliquely ascending to erect, stolons present or absent, not wiry. Leaves strongly dimorphic, sterile leaves with longer and wider pinnae than fertile ones, sterile dying back in winter, fertile persistent, brownish, hardened. Petiole of sterile leaf ca. 1/10–1/5 length of blade, petiole of fertile leaf ± equaling length of blade, bases swollen, persisting as trophopods over winter; vascular-bundles 2, lateral, lunate in cross-section. Blade elliptic (sterile) or narrowly oblong to oblanceolate (fertile), pinnate-pinnatifid or sometimes pinnate with lacerate pinnae in fertile leaves, gradually to nearly abruptly reduced distally to pinnatifid apex, sterile blades herbaceous. Pinnae not articulate to rachis, segment margins entire (sterile); proximal pinnae (several pairs) greatly reduced, sessile, equilateral; costae shallowly grooved adaxially, grooves not continuous from rachis to costae; indument absent on both surfaces or deciduously hairy abaxially. Veins free, simple. Sori in 1 row between midrib and margin, ± round, covered by hardened revolute pinna margin; indusia vestigial, triangular, persistent but not easily seen in mature leaves. Spores greenish, with low folds and minute echinate-cristate elements. x = 40.

Distribution

North temperate regions

Discussion

Matteuccia is one of several genera known to store starch grains in long-persistent petiole bases (trophopods) (W. H. Wagner Jr. and D. M. Johnson 1983). Struthiopteris Willdenow is a later homonym of Struthiopteris Scopoli and hence illegitimate. Pteretis Rafinesque, even though it is the oldest legitimate name, has been rejected in favor of Matteuccia.

Species 3 (1 in the flora).