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Polystichum calderonense Proctor

Monte Guilarte holly fern; Monte Guilarte shield fern

Dryopteridaceae · Puerto Rico

No habitat climate
Photographs not checked iNaturalist was skipped (not asked) when this page was built. Not asked, or not answered, is not "none": nothing here claims there is none. Why the site says it this way.
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Summary

Polystichum calderonense is a rare species of fern known by the common name Monte Guilarte hollyfern. It is endemic to Puerto Rico, where it occurs in the Guilarte State Forest. There are only 57 individual plants remaining. It is a federally listed endangered species of the United States.

Quoted from Wikipedia, "Polystichum calderonense", CC BY-SA 4.0.

About the genus · Polystichum

Polystichum is a genus of ferns in the family Dryopteridaceae, subfamily Dryopteridoideae, according to the Pteridophyte Phylogeny Group classification of 2016. The genus has about 500 species and has a cosmopolitan distribution. The highest diversity is in eastern Asia, with about 208 species in China alone; the region from Mexico to Brazil has at least 100 additional species; Africa, North America, and Europe have much lower diversity. More on Wikipedia ›

Quoted from Wikipedia, "Polystichum", CC BY-SA 4.0.

Cultivation

Nothing derived: no habitat climate for this species.

Climate across the habitat

No habitat climate can be derived: 3 in-range records, none placed to within 10 km. 3 of the 3 in-range records are placed to worse than 10 km, or to no stated accuracy and fewer than three decimals or by something other than a person's observation, and cannot place a climate cell, though they count for the map and its marker.

Natural habitat

Native range as published by WCVP; the marker is where the records are densest and decides nothing.
Openly licensed records inside the range, framed on where they fall.
NativePuerto Rico · regions are the level-3 units of the World Geographical Scheme for Recording Plant Distributions, as Kew's World Checklist records ranges, some under historical names such as Yugoslavia or Czechoslovakia (how).
Map marker18.154, -66.807 · in the densest population, 3 records (100% of those in range)
Evidence usedThe map marker rests on all 3 georeferenced records inside the native range, all openly licensed and shown on the map. Under a dozen records behind the map. No climate across the range is derived for this species. 3 in-range records are placed to worse than 10 km, or with no stated accuracy (admitted only as a person's observation to three decimals), and stay on the map but off the climate.
How this section is made
The map marker: the openly licensed record nearest the middle of the densest 1° population of the 3 in-range records; it decides nothing. Records outside the native range, living specimens and records marked introduced are not used; which records count.

Photographs

Not checked. iNaturalist was skipped (not asked) when this page was built; GBIF's observation records with coordinates hold none. Not a statement that none exist.

Other Polystichum 43 in the reference

Polystichum acrostichoides Polystichum acrostichoides Christmas fern Photo: CC BY, Michael J. PapayPolystichum aculeatum Polystichum aculeatum Hard shield-fern Photo: CC BY, Daniel BuczkiewiczPolystichum andersonii Polystichum andersonii Anderson's holly fern Photo: CC BY, Matt BergerPolystichum andinum Polystichum andinum Dryopteridaceae Photo: CC BY, Constanza Vargas VillegasPolystichum × bicknellii Polystichum × bicknellii Dryopteridaceae Photo: CC BY, Sean Frederick TuckPolystichum braunii Polystichum braunii Braun's holly fern Photo: CC BY, Oleg KosterinPolystichum dracomontanum Polystichum dracomontanum Dryopteridaceae Photo: CC0, author not statedPolystichum drepanum Polystichum drepanum Madeira Shield-Fern Photo: CC0, author not stated Polystichum × dycei Dryopteridaceae Polystichum falcinellum Polystichum falcinellum Madeira Sword-Fern Photo: CC BY, K.P. Polystichum grandifrons Dryopteridaceae Polystichum hancockii Polystichum hancockii Dryopteridaceae Photo: CC BY, Jacy Chen all 44 ›

Names & registers

GBIFPOWOIPNIWFOWikidataWikipediaiNaturalist

The record

Family
Dryopteridaceae
Described by
Proctor
Native to
Puerto Rico
Wild records
3 in range · 3 open

Every figure here is derived from public data by a stated rule and names its source; nothing about this species is written for its page by a person or by AI, apart from the marked, credited quotations. How →

Where this page came from built 2026-10-22
GBIF species record gbif.species answeredasked 2026-10-22
GBIF synonyms gbif.synonyms answeredasked 2026-10-22
GBIF common names gbif.vernacular answeredasked 2026-10-22names fetched 2026-10-22
WCVP native range wcvp.distribution answeredas of 2026-06-04
GBIF occurrence records gbif.occurrences answeredas of 2026-10-21GBIF occurrence download https://doi.org/10.15468/dl.hbdw64, of 2026-10-21; 1 record within 1 km of a botanic garden, herbarium or zoo left out (1 at a botanic garden or arboretum; Wikidata's list)
Habitat climate climate nothing to reportasked 2026-10-223 in-range records, none placed to within 10 km
Wikidata wikidata answeredasked 2026-10-22
Wikipedia wikipedia answeredasked 2026-10-22
iNaturalist photographs, wild inat.photos.wild nothing to reportasked 2026-10-22from iNaturalist's open data of 2026-09-27: research-grade observations with an open-licence photograph, the 24 whose photographs iNaturalist received last (the open data holds no votes); filled 2026-10-22
iNaturalist photographs, cultivated inat.photos.cultivated not asked
GBIF media gbif.media nothing to reportasked 2026-10-22
Wikimedia Commons commons nothing to reportasked 2026-10-22
OpenAlex papers openalex not askednot yet asked for this reference; a later fill takes the papers from OpenAlex's snapshot

Every source is recorded as having answered, reported nothing, refused, failed, not been asked, or answered twice where one answer is taken (“not taken: two items answered”), and, for a source asked when this page was built, when: the figures are as the source held them that day; a source read from a file (Kew's World Checklist, a GBIF download) says "as of" the file's day instead; a row carried from an earlier build of the page names that build instead. Only “nothing to report” is ever shown as an absence. Records came from 2 datasets via GBIF.org; each carries its own licence.

Cultifolio

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