Appalachian Bristle Fern Scientific Name Family Name Crepidomanes intricatum (Farrar) Ebihara & Weakley Hymenophyllaceae Filmy-fern Family Photo credits: Kimberly J. Smith Did you know? This fern exists only in the gametophyte form but at one time, before glaciation, there may have been sporophyte plants that produced spores that allowed the species to expand its range. The author of the species, Donald Farrar, postulates that the loss of sporophytes may have been due to climate change after the Pleistocene Epoch and there still exists the possibility that they remain undiscovered somewhere in the Appalachian Mountains (Farrar 1992). Summary Protection Endangered in New York State, not listed federally. This level of state protection means: listed species are those with: 1) 5 or fewer extant sites, or 2) fewer than 1,000 individuals, or 3) restricted to fewer than 4 U.S.G.S. 7 ½ minute topographical maps, or 4) species listed as endangered by U.S. Department of Interior. Rarity G4G5, S1 A global rarity rank of G4G5 means: Apparently or Demonstrably Secure globally - Uncommon to common in the world, but not rare; usually widespread, but may be rare in some parts of its range; possibly some cause for long-term concern due to declines or other factors. More information is needed to assign a single conservation status. A state rarity rank of S1 means: This plant is endangered/critically imperiled in New York because of extreme rarity (typically 5 or fewer populations or very few remaining individuals) or is extremely vulnerable to extirpation from New York due to biological factors. Conservation Status in New York There are three existing populations but only one of them has been seen since 1983 and it was very small. There are four historical populations from the Catskills and Hudson Valley area that have not been surveyed. NYNHP Conservation Guide - Appalachian Bristle Fern (Crepidomanes intricatum)
Short-term Trends The short-term trend is unknown. Long-term Trends The long-term trend is unknown since there is no good quantity data on populations. Conservation and Management Threats Too much recreational use and climbing on the rocks may threaten the long-term viability of these plants. Conservation Strategies and Management Practices More research is also needed on the proper management procedures to protect and increase populations. Research Needs Research is needed into how climate change will affect these populations and the type of habitat they prefer. More research is also needed on the proper management procedures to protect and increase populations. Habitat In New York, Appalchian Bristle Fern has been found on ledges of conglomerate rock amongst large mossy boulders and on rock houses of sandstone conglomerate (New York Natural Heritage Program 2013). On basic and acidic rock in sheltered caves, pockets, and crevices (Haines 2011). Deep shade of non-calcareous rock houses (Rhoads and Block 2000). On non-calcareous rocks in deeply sheltered crevices and grottoes and occasionally epiphytic (Flora of North America 1993). Rock houses and moist, overhanging cliffs, usually on sandstone (Gleason and Cronquist 1991). Associated Ecological Communities Acidic Talus Slope Woodland An open to closed canopy woodland that occurs on talus slopes (slopes of boulders and rocks, often at the base of cliffs) composed of non-calcareous rocks such as granite, quartzite, or schist. Talus Cave Community The community that occurs in small crevices and caves with walls of boulders or cobbles, typically in a talus slope at the base of a cliff. This includes talus slopes that are cool enough to allow winter ice to remain within the talus through all or part of the summer; these are known as ice caves. NYNHP Conservation Guide - Appalachian Bristle Fern (Crepidomanes intricatum) 2
Other Probable Associated Communities Ice cave talus community Terrestrial cave community Identification Comments Trichomanes intricatum occurs only as its vegetative form (gametophyte) with sexually reproducing forms (sporophytes) as yet undocumented. The gametophyte is entirely filamentous, much branched, and remains persistent after maturity. Its cup-like cluster of cells (gemmae) are composed of short filaments of undifferentiated cells. Although individual gametophytes may be only a few millimeters thick, they may grow together in moss-like mats up to a square meter in size. Best Life Stage for Identifying This Species The vegetative form (gametophyte) is the only life stage known for this species. Examination of a small portion of the plant bearing gemmae cups is needed for positive identification. Due to its rarity this species should not be collected. The Best Time to See The vegetative form (gametophyte) is typically present beginning in early March and persists through November. Vegetative Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Similar Species The time of year you would expect to find Appalachian Bristle Fern in New York. This species is only known only from the gametophyte generation, as no sporophytes have ever been documented. It is more likely to be quickly passed over as a moss or liverwort than confused with another fern, and is the only Trichomanes known from New York. The filamentous gametophytes of Trichomanes can be distinguished from algae and from the thread-like chains of cells (protonema) in the haploid phase of mosses by their short cells with numerous disc-shaped chloroplasts, by the presence of short, brown, unicellular rhizoids, and by their production of specialized gemmifer cells and gemmae (FNA 1993). Taxonomy Kingdom Phylum Plantae Filicinophyta NYNHP Conservation Guide - Appalachian Bristle Fern (Crepidomanes intricatum) 3
Class Ferns (Filicopsida) Order Filicales Family Additional Common Names Appalachian Gametophytes Weft Fern Hymenophyllaceae (Filmy-fern Family) Synonyms Trichomanes intricatum (Farrar) Additional Resources Links Flora of North America http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=233501311 New York Flora Atlas http://www.newyork.plantatlas.usf.edu/plant.aspx?id=1609 USDA Plants Database http://plants.usda.gov/java/namesearch?mode=sciname&keywordquery= TRICHOMANES+INTRICATUM NatureServe Explorer http://natureserve.org/explorer/servlet/natureserve?searchname=trichomanes+intri CATUM Google Images http://images.google.com/images?q=trichomanes+intricatum References Flora of North America Editorial Committee. 1993. Flora of North America, North of Mexico. Volume 2. Pteridophytes and Gymnosperms. Oxford University Press, New York. 475 pp. Gleason, Henry A. and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States and Adjacent Canada. The New York Botanical Garden, Bronx, New York. 910 pp. Holmgren, Noel. 1998. The Illustrated Companion to Gleason and Cronquist's Manual. Illustrations of the Vascular Plants of Northeastern United States and Adjacent Canada. The New York Botanical Garden, Bronx, New York. Keys, Jr.,J.; Carpenter, C.; Hooks, S.; Koenig, F.; McNab, W.H.; Russell, W.;Smith, M.L. 1995. Ecological units of the eastern United States - first approximation (cd-rom), Atlanta, GA: U.S. Department of Agriculture, Forest Service. GIS coverage in ARCINFO format, selected imagery, and map unit tables. Mitchell, Richard S. and Gordon C. Tucker. 1997. Revised Checklist of New York State Plants. Contributions to a Flora of New York State. Checklist IV. Bulletin No. 490. New York State Museum. Albany, NY. 400 pp. NatureServe. 2005. NatureServe Central Databases. Arlington, Virginia. USA NYNHP Conservation Guide - Appalachian Bristle Fern (Crepidomanes intricatum) 4
New York Flora Association. 1990. Preliminary vouchered atlas of New York State flora. New York Flora Association, New York State Museum Institute. 498 pp. Weldy, T. and D. Werier. 2010. New York flora atlas. [S.M. Landry, K.N. Campbell, and L.D. Mabe (original application development), Florida Center for Community Design and Research http://www.fccdr.usf.edu/. University of South Florida http://www.usf.edu/]. New York Flora Association http://wwws.nyflora.org/, Albany, New York New York Natural Heritage Program 625 Broadway, 5th Floor, Albany, NY 12233-4757 Phone: (518) 402-8935 acris@nynhp.org This project is made possible with funding from: - New York State Department of Environmental Conservation Hudson River Estuary Program - Division of Lands & Forests, Department of Environmental Conservation - New York State Office of Parks, Recreation and Historic Preservation Information for this guide was last updated on Aug 21, 2017 This guide was authored by Elizabeth Spencer NYNHP Conservation Guide - Appalachian Bristle Fern (Crepidomanes intricatum) 5