Rhizophyllum means with rooting leaves.
Rhizome: erect, short, scales clathrate, dark brown, narrowly deltate, to 3mm.
Frond: 30 cm high by 5 cm wide, evergreen, monomorphic but fertile leaves generally larger than sterile leaves, blade/stipe ratio: 1:1 to 9:1 or blade shorter than stipe.
Stipe: reddish brown at base, becoming green, dark brown, narrowly deltate scales at base,minute, club-shaped hairs above, vascular bundles: 2 C-shaped, back to back, uniting to 1 upwards to an X-shape.
Blade: simple, narrowly deltate to linear-lanceolate, variable in size and shape, basal lobes usually rounded, but sometimes pointed, even on 1 plant, apex rounded to very long-tapering and, if tapering, generally rooting at tip, leathery, sparsely hairy, hairs more numerous below than above.
Pinnae: none; costae rachis green, dull, nearly glabrous, grooved above; margins entire to sinuate, rarely irregularly incised; veins obscure, netting near the midrib.
Sori: linear, but following the veins, scattered somewhat irregularly over blade, often joined at vein junction, indusium: green, shriveling, inconspicuous, along the vein, sporangia: golden yellow young, reddish-brown later, maturity: midsummer to early fall.
Habitat: shady, mossy limestone rocks, occasionally sandstone substrates.
Distribution: eastern North America.
Hardy to -35°C, USDA Zone 3.
There are few temperate ferns with simple fronds and fewer still developing new plants at frond apex. Yes, there is Camptosoros sibiricus, a smaller plant, not listed here, whose fronds are widest well above a constricted base vs. widest at the base here.
Camptosorus rhizophyllus (Linnaeus) Link