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1 Leaves simple, unlobed (or with a few, irregular forkings in A. septentrionale); veins free or anastamosing-areolate. |
..2 Leaf blades 0-3 mm wide, linear, forking or with a few toothlike projections; [V. Schaffneria clade; A. septentrionale subclade] |
..2 Leaf blades 10-40 mm wide, lanceolate, lance-attenuate, or oblong. |
....3 Leaf apex long-attenuate and characteristically producing plantlets at the tip; veins anastomosing; [V. Schaffneria clade; A. cordatum subclade] |
....3 Leaf apex acuminate to obtuse, not producing plantlets at the tip; veins free. |
......4 Leaf blade cuneate at base; [of FL southwards]; [III. Neottopteris clade] |
......4 Leaf blade cordate at base; [of AL northwards]; [II. Phyllitis clade; Phyllitis subclade]. |
........5 Longer indusia of each frond avg. 1.2 cm long; leaves (1-) avg. 2.3 (-3.5) dm long; [native in TN, AL, and elsewhere, in natural limestone sinkholes] |
........5 Longer indusia of each frond avg. 1.7 cm long; leaves (1-) avg. 3 (-6) dm long; [rarely introduced in North America, typically in artificial settings, such as old well shafts] |
1 Leaves pinnatifid (at least in the lower half of the leaf), pinnate, pinnate-pinnatifid, bipinnate, or tripinnate, the apex obtuse, acute, acuminate, or attenuate; veins free. |
..........6 Rachis shiny black or dark brown throughout its length; rachis not grooved on its upper surface; leaves pinnate, the outline of the leaf blade linear, lanceolate, or oblanceolate, with more-or-less parallel sides for much of its length. |
............ 7 Pinnae orbicular to obovate-oblong, 1-2× as long as wide, the base more-or-less symmetrical (if auriculate, only slightly so and on the side of the pinna toward the base of the leaf); old leaf rachises often with persistent projections left from the disarticulation of the pinnae; [VI. A. trichomanes clade; A. trichomanes subclade]. |
............ ..8 Sori 4-9 (-12) per pinna, up to 3 mm long; rhizome scales up to 5 mm long; petiole relatively thicker, blackish-brown; pinnae mostly opposite, oblong, spaced more closely, thicker in texture, set at a nearly right angle to the rachis, rarely at all auriculate; spores mostly 34-43 μ long; stomate guard cells mostly 41-49 μ long; [of calcareous rocks] |
............ ..8 Sori 4-6 (-9) per pinna, up to 2 mm long; rhizome scales up to 3 mm long; petiole relatively thin, shiny, coppery or bronze; pinnae mostly alternate, suborbicular, spaced more distantly, thinner in texture, set at a fairly oblique angle to the rachis, often slightly auriculate on the side of the pinna toward the leaf base; spores mostly 29-36 μ long; stomate guard cells mostly 38-43 μ long; [mostly of noncalcareous rocks] |
............ 7 Pinnae oblong-rectangular, 2× or more as long as wide, the base asymmetrical or auricled (more prominently auricled on the side of the pinna toward the tip of the leaf); old leaf rachises lacking persistent projections left from the disarticulation of the pinnae. |
............ ....9 Leaves slightly dimorphic, the fertile upright and larger, the sterile spreading and smaller; pinna auricles prominent, often overlapping the rachis; [terrestrial, often not associated with rock outcrops]; [V. Schaffneria clade; A. incisum subclade] |
............ ....9 Leaves not dimorphic; pinna auricles less prominent, usually not overlapping the rachis; [epipetric, always growing in crevices of rock outcrops or in thin soil immediately adjacent to exposed rock]; [VI. A. trichomanes clade; A. monanthes subclade]. |
............ ......10 Main vein of the pinna running along the basal edge; sori 1 (-3) per pinna, 1.5-3 mm long, borne along the basal edge, the indusium translucent, whitish, opening toward the leaf tip |
............ ......10 Main vein of the pinna running more-or-less medially; sori 4-10 per pinna (on well-developed pinnae), 1.0-1.5 mm long, borne on both sides of the main vein, the indusium opaque, greenish, opening toward the pinna tip. |
............ ........11 Pinnae margins subentire; pinnae blue-green, coriaceous, borne at right angles to the rachis or slightly reflexed, usually strictly opposite throughout the entire length of the leaf blade |
............ ........11 Pinnae margins shallowly crenate or crenate-serrate; pinnae bright-green, subcoriaceous, borne at right angles to the rachis or ascending, opposite below but usually becoming alternate in the apical 1/3-1/2 of the leaf blade |
............ ..........12 Pinna margins crenate to serrate; pinna base lacking an auricle, or the auricle rudimentary; veins evident; spores 64 per sporangium |
............ ..........12 Pinna margins shallowly crenate; pinna base with auricle; veins obscure; spores 32 per sporangium |
..........6 Rachis dull green throughout its length, or at least toward the tip; rachis grooved on the upper surface, at least in the green portion; leaves pinnatifid to tripinnate, the outline of the leaf blade narrowly to broadly triangular, widest at the base (or slightly above the base in A. abscissum) (except A. dentatum). |
............ ............ 13 Petiole shiny black or brown throughout its length (from base to first leaflet). |
............ ............ ..14 Leaves bipinnate at the base, pinnate-pinnatifid above; spores normal; [XI. Pleurosorus clade; Onopteris subclade] |
............ ............ ..14 Leaves pinnate at the base, pinnatifid above; spores abortive (or normal in A. tutwilerae, known only from Hale County, AL); [V. Schaffneria clade; reticulation between two subclades]. |
............ ............ ....15 Spores abortive |
............ ............ ....15 Spores normal; [endemic (as far as known) to Hale County, AL] |
............ ............ 13 Petiole partially or entirely green (darkened or not at its base). |
............ ............ ......16 Leaves pinnatifid or 1-pinnate through most or all of their lengths (sometimes pinnate-pinnatifid at the base of the leaf). |
............ ............ ........17 Leaves pinnatifid, sometimes fully pinnate at the base; spores normal |
............ ............ ........17 Leaves pinnate (sometimes pinnate-pinnatifid at the base of the leaf in A. ×trudellii and A. dentatum); spores normal or abortive. |
............ ............ ..........18 Pinnae 1-8 on each side of the rachis below the merely pinnatifidly lobed upper half of the leaf; blades deltoid to broadly isosceles-triangular, 1-3× as long as wide; [of FL and rarely n. AL]. |
............ ............ ............ 19 Pinnae 4-8 on each side of the rachis below the merely pinnatifidly lobed upper half of the leaf; basalmost pinnae ca. 3× as long as wide, toothed but not cut; [VIII. Asplenium clade] |
............ ............ ............ 19 Pinnae 0-2 (-4) on each side of the rachis below the merely pinnatifidly lobed upper half of the leaf; basalmost pinnae ca. 1.5× as long as wide, both toothed and cut (lobed); [V. Schaffneria clade; A. delavayi subclade] |
............ ............ ..........18 Pinnae 5-35 on each side of the rachis; blades lanceolate or linear, 4-7× as long as wide; [collectively widespread]. |
............ ............ ............ ..20 Pinnae lanceolate, 3-10× as long as wide, with an acroscopic auricle at the base of the larger pinnae; epiphytic on bark; [of FL peninsula]; [I. A. erosum clade] |
............ ............ ............ ..20 Pinnae ovate, obovate, or deltoid, 1-2.5× as long as wide, lacking an auricle; epipetric; of FL peninsula and also inland from nc. GA and nc. AL northwards]. |
............ ............ ............ ....21 Leaf blade outline with nearly parallel margins, with a blunt tip; spores normal; on moist outcrops of limestone; [of FL peninsula] |
............ ............ ............ ....21 Leaf blade outline tapering evenly from near or at the base, with a long-attenuated tip; spores abortive; on moist outcrops of felsic sedimentary or metamorphic rocks, such as sandstone, phyllite, schist; [inland from nc. GA and nc. AL northwards] |
............ ............ ......16 Leaves 2-pinnate at least basally, to 3-pinnate. |
............ ............ ............ ......22 [inland and more northern, from c. AL and c. GA northwards]. |
............ ............ ............ ........23 Petiole darkened toward the base; pinnules toothed, lacerate, pinnatifid, or pinnate; leaves bipinnate to tripinnate, the leaf blades lanceolate-ovate to lanceolate-oblong; ultimate leaf segments sessile or nearly so; [of acidic rocks] ; [XI. Pleurosorus clade; Onopteris subclade] |
............ ............ ............ ........23 Petiole entirely green; pinnules toothed; leaves bipinnate, the leaf blades ovate-triangular; ultimate leaf segments mostly stalked; [of calcareous rocks]; [XI. Pleurosorus clade; Pleurosorus subclade] |
............ ............ ............ ......22 [Coastal Plain and southern, of FL]; [VIII. Asplenium clade]. |
............ ............ ............ ..........24 Rachis darkened, at least in its lower portion. |
............ ............ ............ ............ 25 Leaves 2-pinnate basally and pinnate-pinnatifid upwards; spores of different and irregular shapes and sizes |
............ ............ ............ ............ 25 Leaves 2-3-pinnate; spores normal |
............ ............ ............ ..........24 Rachis green throughout. |
............ ............ ............ ............ ..26 Leaves 2-pinnate through most of their length; spores normal |
............ ............ ............ ............ ..26 Leaves 2-pinnate only basally, mostly pinnate-pinnatifid to merely pinnate upwards; spores of different and irregular shapes and sizes |