Black-stemmed Spleenwort

It is a small fern with pinnate fronds, growing in erect tufts, with a shiny black stipe and rachis (stem and leaf axis). Sterile and fertile fronds are similar in appearance. The roots are thin and wiry and do not proliferate to form new plants. The rhizome is short and erect, about 2 millimeters (0.08 in) in diameter. It has variously been described as sometimes branching or unbranched. It bears stiff filamentous, linear, or lance-shaped scales, which are blackish in color and obscurely clathrate (bearing a lattice-like pattern) or entirely black. The scales are 3 to 5 millimeters (0.1 to 0.2 in) long and 0.2 to 0.6 millimeters (0.008 to 0.02 in) wide, with untoothed, often brown, margins and long, drawn-out tips. Leaves are erect and borne in dense clumps, varying in size from 3 to 45 centimeters (1.2 to 18 in) long and from 0.5 to 2.5 centimeters (0.20 to 0.98 in) wide. The stipe (the stalk of the leaf, below the blade) is straight and stiff and a glossy black to purplish-black in color. It may be smooth or bear scattered blackish-brown, threadlike scales 1 to 1.5 millimeters (0.039 to 0.059 in) long and tan, club-shaped hairs 0.1 to 0.2 millimeters (0.004 to 0.008 in) long which are appressed (lie flat against the stipe). …

Asplenium resiliens is found in the southern United States, Mexico, Hispaniola, Jamaica, Guatemala, and South America from Colombia and Venezuela south to northern Argentina, Uruguay, and Brazil. Within the United States, it is found from Florida west to Arizona and southern Nevada and north to south-central Pennsylvania. It is found throughout most of Mexico, but is most abundant in the northeast, in Nuevo León and Coahuila. In Guatemala, it is known from the western departments of Huehuetenango, El Quiché, and Sololá. In Argentina, its distribution follows the arc of the mountains from Jujuy Province southward to the Sierra de la Ventana in Buenos Aires Province; it is also known from Mendoza Province, in the west of the country, from the departments of Las Heras and Luján de Cuyo. It is found on or at the base of cliffs or sinkholes, on limestone or other alkaline rocks, although specimens have also been reported from crevices in granite and sandstone. Growth on soil is rare. It may be found in forests or on boulders, ledges, and in crevices of cliffs. Plants grow at altitudes ranging from 100 meters (300 ft) (in North America) to 3,900 meters (13,000 ft) (in Guatemala). Plants at the higher altitudes (3,000 meters (9,800 ft) and above) are stunted and more compact than usual, with leaves 4 to 10 centimeters (2 to 4 in) long and overlapping pinnae a few millimeters in length. …

Asplenium resiliens is a triploid and reproduces apogamously, producing 32 spores per sporangium. Specimens with 64 well-formed spores per sporangium, believed to be sexually reproducing, were collected from Green Gulch in the Chisos Mountains in 1937, although other specimens since collected in the area have the typical 32 spores per sporangium. While globally secure (G5), it is considered an endangered species in many of the states at the northern edge of its North American range. NatureServe considers it to be critically imperiled (S1) in Colorado, Illinois, Maryland, Mississippi, Nevada, Ohio, Pennsylvania, South Carolina, and Utah, imperiled (S2) in Indiana, Kansas and North Carolina, and vulnerable (S3) in West Virginia. It has become extinct in Louisiana since the limestone caprock of a salt dome at Winnfield, the only location for the fern in the state, was quarried away. It is also believed to be extinct in Ohio, where it was last collected in 1900, although suitable habitat still exists in the state. Quarrying of the calcareous rocks on which it grows poses a "low-level" threat to the species.

Asplenium resiliens is tolerant of cold to USDA hardiness zone 6. It prefers moist conditions, a basic potting soil, and a medium amount of light.