Cryptogramma acrostichoidesR.Br.

American parsley fernAmerican rockbrake

WFO wfo-0001109543 Accepted WFO 2026-06 8 photographs CC BY

Plate 1 figs. a–h · 8 separate observations

Cryptogramma acrostichoides, photographed by James H. Thomas
fig. a James H. Thomas, CC BY 4.0 / 2022-06-04 / obs. 203708258
Cryptogramma acrostichoides, photographed by James H. Thomas
fig. b James H. Thomas, CC BY 4.0 / obs. 202216857
Cryptogramma acrostichoides, photographed by Timothy McNitt
fig. c Timothy McNitt, CC BY 4.0 / obs. 203206689
Cryptogramma acrostichoides, photographed by James H. Thomas
fig. d James H. Thomas, CC BY 4.0 / obs. 199532242
Cryptogramma acrostichoides, photographed by Timothy McNitt
fig. e Timothy McNitt, CC BY 4.0 / obs. 199288570
Cryptogramma acrostichoides, photographed by James H. Thomas
fig. f James H. Thomas, CC BY 4.0 / obs. 199220921
Cryptogramma acrostichoides, photographed by James H. Thomas
fig. g James H. Thomas, CC BY 4.0 / obs. 199221130
Cryptogramma acrostichoides, photographed by James H. Thomas
fig. h James H. Thomas, CC BY 4.0 / obs. 198465670

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

The specimen a real sheet, in a real collection

Herbarium
The New York Botanical Garden
Accession
02313153
Filed as
Cryptogramma acrostichoides R.Br.
Det. by
J. T. Mickel
Collected
N. H. Holmgren 1983-08-23
Origin
US
The sheet
View the digitised specimen (CC BY 4.0)

A real pressed plant, in a real collection, under the accession number above. Not an illustration of one. The holding institution does not serve this sheet’s image to third parties, so there is no photograph here. The record is real and the link goes to it. Where we hold no openly licensed sheet for a species this section is simply absent, and where a sheet never recorded who determined it, that field stays empty rather than being filled in. Roughly half of all herbarium sheets never recorded a determiner, which is ordinary.

Native range 23 botanical countries

Regions where Cryptogramma acrostichoides is native: Kamchatka, Magadan, Alaska, Alberta, Arizona, British Columbia, California, Colorado, Idaho, Manitoba, Michigan, Montana, Nevada, New Mexico, Northwest Territories, Ontario, Oregon, Saskatchewan, South Dakota, Utah, Washington, Wyoming, Yukon KamchatkaMagadanAlaskaAlbertaArizonaBritish ColumbiaCaliforniaColoradoIdahoManitobaMichiganMontanaNevadaNew MexicoNorthwest TerritoriesOntarioOregonSaskatchewanSouth DakotaUtahWashingtonWyomingYukon
Native distribution of Cryptogramma acrostichoides, after Kew’s World Checklist of Vascular Plants. Introduced, extinct and doubtful records are excluded, so this is where the plant is from, not everywhere it now grows.
RegionTDWG codeContinent
Alaska ASK NORTHERN AMERICA
Alberta ABT
Arizona ARI
British Columbia BRC
California CAL
Colorado COL
Idaho IDA
Manitoba MAN
Michigan MIC
Montana MNT
Nevada NEV
New Mexico NWM
Northwest Territories NWT
Ontario ONT
Oregon ORE
Saskatchewan SAS
South Dakota SDA
Utah UTA
Washington WAS
Wyoming WYO
Yukon YUK
Kamchatka KAM ASIA-TEMPERATE
Magadan MAG

Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.

Where it actually grows measured, from 1,972 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -17.2 °C -5.2 °C 2.7 °C
Warmest month, mean daily high 15.2 °C 21.8 °C 27.1 °C
Annual rainfall 637 mm 1,752 mm 3,673 mm
Rainfall in the driest quarter 58 mm 170 mm 354 mm

It is found where winters are severely cold. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 1,972 research-grade observations of Cryptogramma acrostichoides that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.

This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one.

Also published as 8 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

  • Allosorus acrostichoides Spreng.
  • Allosorus crispus var. acrostichoides (R.Br.) Milde
  • Allosorus foveolatus Rupr.
  • Cryptogramma crispa subsp. acrostichoides (R.Br.) Hultén
  • Cryptogramma crispa var. acrostichoides (R.Br.) C.B.Clarke
  • Cryptogramma stelleri var. foveolata Gilbert
  • Gymnogramma acrostichoides (R.Br.) C.Presl
  • Phorolobus acrostichoides Fée

Sourcesevery claim on this page

  1. World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
  2. iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
  3. Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
  4. Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.

We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.