Thelypteridaceae is a family of about 900 species of ferns in the order Polypodiales. In the Pteridophyte Phylogeny Group classification of 2016, it is placed in the suborder Aspleniineae. Alternatively, the family may be submerged in a very broadly defined family Aspleniaceae as the subfamily Thelypteridoideae.
Asplenium platyneuron, commonly known as ebony spleenwort or brownstem spleenwort, is a fern native to North America east of the Rocky Mountains. It takes its common name from its dark, reddish-brown, glossy stipe and rachis, which support a once-divided, pinnate leaf. The fertile fronds, which die off in the winter, are darker green and stand upright, while the sterile fronds are evergreen and lie flat on the ground. An auricle at the base of each pinna points towards the tip of the frond. The dimorphic fronds and alternate, rather than opposite, pinnae distinguish it from the similar black-stemmed spleenwort.
Claytosmunda is a genus of fern. It has only one extant species, Claytosmunda claytoniana, the interrupted fern, native to Eastern Asia, Eastern United States, and Eastern Canada.
Thelypteris is a genus of ferns in the subfamily Thelypteridoideae, family Thelypteridaceae, order Polypodiales. Two radically different circumscriptions of the genus are in use as of January 2020. In the Pteridophyte Phylogeny Group classification of 2016, the genus is a very small one with about two species. In other approaches, the genus is the only one in the subfamily Thelypteridoideae, and so includes between 875 and 1083 species.
Asplenium rhizophyllum, the (American) walking fern, is a frequently-occurring fern native to North America. It is a close relative of Asplenium ruprechtii which is found in East Asia and also goes by the common name of "walking fern".
Dryopteris goldieana, commonly called Goldie's wood fern, or giant wood fern is a fern native to the eastern United States and adjacent areas of Canada, from New Brunswick to Ontario and Georgia. It is the largest native North American species of Dryopteris and along with ostrich fern it is one of the largest ferns in eastern North America. Specimens are known with fronds six feet tall. D. goldieana hybridizes with many other species of Dryopteris and the hybrids tend to be larger than the pure species. It was named by William Hooker in honor of its discoverer, John Goldie. The epithet was originally published as goldiana, but this is regarded as a misspelling to be corrected.
Asplenium septentrionale is a species of fern known by the common names northern spleenwort and forked spleenwort. It is native to Europe, Asia and western North America, where it grows on rocks. Its long, slender leaves give it a distinctive appearance. Three subspecies exist, corresponding to a tetraploid and a diploid cytotype and their triploid hybrid.
Amauropelta noveboracensis, the New York fern, is a perennial species of fern found throughout the eastern United States and Canada, from Louisiana to Newfoundland, but most concentrated within Appalachia and the Atlantic Northeast. New York ferns often forms spreading colonies within the forests they inhabit.
Asplenium pinnatifidum, commonly known as the lobed spleenwort or pinnatifid spleenwort, is a small fern found principally in the Appalachian Mountains and the Shawnee Hills, growing in rock crevices in moderately acid to subacid strata. Originally identified as a variety of walking fern, it was classified as a separate species by Thomas Nuttall in 1818. It is believed to have originated by chromosome doubling in a hybrid between walking fern and mountain spleenwort, producing a fertile tetraploid, a phenomenon known as alloploidy; however, the hypothesized parental hybrid has never been located. It is intermediate in morphology between the parent species: while its leaf blades are long and tapering like that of walking fern, the influence of mountain spleenwort means that the blades are lobed, rather than whole. A. pinnatifidum can itself form sterile hybrids with several other spleenworts.
Asplenium bradleyi, commonly known as Bradley's spleenwort or cliff spleenwort, is a rare epipetric fern of east-central North America. Named after Professor Frank Howe Bradley, who first collected it in Tennessee, it may be found infrequently throughout much of the Appalachian Mountains, the Ozarks, and the Ouachita Mountains, growing in small crevices on exposed sandstone cliffs. The species originated as a hybrid between mountain spleenwort and ebony spleenwort ; A. bradleyi originated when that sterile diploid hybrid underwent chromosome doubling to become a fertile tetraploid, a phenomenon known as allopolyploidy. Studies indicate that the present population of Bradley's spleenwort arose from several independent doublings of sterile diploid hybrids. A. bradleyi can also form sterile hybrids with several other spleenworts.
Deparia acrostichoides, commonly called silvery glade fern or silvery spleenwort, is a perennial species of fern. Its range includes much of the eastern United States and Canada, from Ontario to Nova Scotia and Georgia to Louisiana, as well as eastern Asia in China, Russia, Japan and Korea. The name silvery comes from the fact that the indusia on the underside of the leaf have a silver color when the sori are close to ripening.
Parathelypteris nevadensis, synonym Thelypteris nevadensis, is a species of fern known by the common names Sierra marsh fern, Sierra wood fern, and Nevada marsh fern. It is native to western North America from British Columbia to the mountains of northern California, where it grows in moist wooded areas, streamsides, meadows, and seeps. It is known from two locations in Idaho, as well. Despite its name it is not found in Nevada, rather, it was named for the Sierra Nevada, where it does occur in the northern mountains. It produces a dense cluster of long, feathery leaves which may be up to a meter long. It is rhizomatous and it sometimes forms colonies. The leaves die back in winter. Each leaf is made up of leaflets lined with smaller segments. The undersides are glandular and resinous and sometimes hairy.
Abacopteris is a small genus of ferns in the family Thelypteridaceae.
Goniopteris verecunda, synonym Thelypteris verecunda, is a rare species of fern known by the common name Barrio Charcas maiden fern. It is endemic to Puerto Rico, where it is known from only three localities. It is a federally listed endangered species of the United States.
Plenasium banksiifolium is a fern in the family Osmundaceae. The genus Plenasium is recognized in the Pteridophyte Phylogeny Group classification of 2016 (PPG I); however, some sources place all Plenasium species in a more broadly defined Osmunda, treating this species as Osmunda banksiifolia. It is native along the Pacific coast of Asia, being found in the Kamchatka Peninsula, the Ryukyu Islands, Japan, southeast China, Taiwan, the Philippines, Borneo, Sulawesi and Java. P. banksiifolium, which can reach a height of 1.5 m, is the largest species in the genus and has ornamental value.
Asplenium × ebenoides is a hybrid fern native to eastern North America, part of the "Appalachian Asplenium complex" of related hybrids. The sterile offspring of the walking fern (A. rhizophyllum) and the ebony spleenwort (A. platyneuron), A. × ebenoides is intermediate in morphology between its two parents, combining the long, narrow blade of A. rhizophyllum with a dark stem and lobes or pinnae similar to those of A. platyneuron. While A. × ebenoides is generally sterile, fertile specimens with double the number of chromosomes are known from Havana Glen, Alabama. These fertile allotetraploids were reclassified as a separate species named A. tutwilerae in 2007, retaining the name A. × ebenoides for the sterile diploids only.
Asplenium tutwilerae is a rare epipetric fern found only in Hale County, Alabama, United States. A. tutwilerae is a fertile allotetraploid, formed by the chromosomal doubling of a specimen of the sterile diploid A. × ebenoides, a hybrid of A. platyneuron and A. rhizophyllum. Except for its spores, which are fertile rather than malformed, A. tutwilerae is essentially identical to A. × ebenoides and was described as part of that species until 2007. It is named in honor of Julia Tutwiler, who discovered the only known wild population at Havana Glen in 1873.
Dendroconche annabellae is a species of fern in the family Polypodiaceae, subfamily Microsoroideae. It is endemic to Papua New Guinea.
