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Trimezia martinicensis; photograph (c) vitordematos12, some rights reserved (CC BY-SA) CC BY-SA(c) vitordematos12, some rights reserved (CC BY-SA) · observed growing wild · 2025-12-13

Trimezia martinicensis (Jacq.) Herb.

Martinique trimezia; Forenoon Yellow Flag; Yellow Walking Iris

Iridaceae · Costa Rica, Honduras +12 · listed by its family as a bulb, tuber or caudex

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Trimezia martinicensis, photograph (c) Guillaume Delaitre, some rights reserved (CC BY)Trimezia martinicensis, photograph (c) Guillaume Delaitre, some rights reserved (CC BY)Trimezia martinicensis, photograph (c) Guillaume Delaitre, some rights reserved (CC BY)Trimezia martinicensis, photograph (c) Guillaume Delaitre, some rights reserved (CC BY)Trimezia martinicensis, photograph (c) Guillaume Delaitre, some rights reserved (CC BY)Trimezia martinicensis, photograph (c) chrisdt, some rights reserved (CC BY) 79 photographs ›
Habitat figures
Cold floor (1 night in 100)
20.4°C
Record low 18.1 °C in 44 years, at a typical spot in the range NASA POWER
Warmest month, mean daily high
27°C
May, Jun, Jul, Aug, Sep, Oct and Nov at the habitat CHELSA
Rain a year (median across the range)
1,957mm
12 months of 25 mm or more in the median year CHELSA
Open-sky light
31–41DLI
Lowest to highest month (DLI) CHELSA
The year in the habitat's months, not shifted
  1. Jan
  2. Feb
  3. Mar
  4. Apr
  5. May
  6. Jun
  7. Jul
  8. Aug
  9. Sep
  10. Oct
  11. Nov
  12. Dec
A sharp rainy season, May to November (the habitat's months, not shifted), in a year of even temperature. rain rule, CHELSA
Not shifted: the shift rule does not apply to this habitat. The chart is in the habitat's months.

Summary

Trimezia martinicensis is a species of bulbous plant in the family Iridaceae. Originally from South America and the West Indies, it is now widely naturalized throughout the tropics. Common names include Martinique trimezia, yellow walking iris and forenoon yellow flag.

Quoted from Wikipedia, "Trimezia martinicensis", CC BY-SA 4.0.

About the genus · Trimezia

Trimezia is a genus of flowering plants in the family Iridaceae, native to the warmer parts of southern Mexico, Central America, South America, Florida, and the West Indies. Trimezia is placed in the tribe Trimezieae. The division of the tribe into genera has varied considerably. More on Wikipedia ›

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

Cultivation

Grouped as a bulb, tuber or caudex, listed under the family Iridaceae in the archetype table, and Kew describes it as “rhizomatous geophyte”.

Seasons

The rain rule reads a sharp season: 70% of the median year's rain (1,365 mm of 1,904 mm) falls in May to November. The temperature curve is flat, 1.6 °C between the warmest and coldest month, so the growing-season rule does not infer a growing season from it. Months are the habitat's, southern hemisphere. The temperature curve moves under 4 °C between the warmest and coldest month, where the shift rule does not apply, so they are not shifted for a collection elsewhere.

Rain

1,904 mm in the median year at the habitat, 1,365 mm of it May to November. Wettest month October at 220 mm, driest month February at 84 mm. Across the grid cells of the range the year's total runs 1,276 mm to 3,359 mm, the 10th to 90th percentile of each cell's own year. The median of the cells' own yearly totals, 1,957 mm, is the year's rain at the top of the page; the 1,904 mm here is the median year's, the twelve monthly medians added, which the rain rule reads. Habitat calendar, southern hemisphere; median year across the grid cells of the range, CHELSA.

Light

Open sky over the habitat: 31 to 41 mol/m²/day across the year (daily light integral, median year across the grid cells of the range, CHELSA; the lowest 10th-percentile month across the cells is 26, the highest 90th-percentile month 43).

Warmth and air
Temperature

Coldest: the 1st-percentile night over 44 years at a typical spot in the range is 20.4 °C, the absolute minimum 18.1 °C, no frost in 44 years (NASA POWER daily minima). Warmest: the 99th-percentile day is 35.2 °C. Monthly means: the coldest month's mean nightly low 22.4 °C in January and February (across the grid cells of the range 15.7 °C to 24.2 °C), the warmest month's mean daily high 27.3 °C in September (median year across the grid cells of the range, CHELSA). Cold floor: 20.4 °C, which is the 1st-percentile night over 44 years at a typical spot in the range (NASA POWER).

Humidity

Relative humidity at the habitat: 64 to 68% across the year (monthly means, median year across the grid cells of the range, CHELSA). A figure about the air, saying nothing about how the plant takes water.

How this section is made

Each card states this species' habitat figures with their sources, and what two fixed rules read from them; nothing here says what the plant does, wants or tolerates. The rules · the terms.

Seasons. Read from the median year of CHELSA monthly rainfall and mean temperature across the grid cells of the range: the rain rule takes the smallest set of months carrying 70% of the rain and calls it winter when its mean is more than half a degree below the year's, summer when more than that above, and neither in between; the temperature rule, used only under 120 mm, names the cooler six months when they are at least a degree cooler than the other six. Months are shifted for the other hemisphere only where the temperature curve moves 4 °C or more and the habitat lies 10° or more from the equator. A reading of the curves, not an observation of the plant.

Rain. CHELSA monthly precipitation, median year across the grid cells of the range. The rain that falls where the species is recorded; nothing about how the plant takes water.

Light. CHELSA shortwave radiation at each envelope cell, a daily-mean flux taken to a daily total and converted at 2.07 mol of PAR per MJ. The sky over the habitat, measured; what reaches a plant under a rock, a shrub or a shade cloth is not.

Temperature. NASA POWER daily minima and maxima over 44 years at a typical spot in the range, lapse-corrected -20 m to its elevation; CHELSA monthly means, median year across the grid cells of the range. The cold floor is the 1st-percentile night named in its sentence. Not a measured survival limit for any plant in a pot.

Humidity. CHELSA relative humidity, median year across the grid cells of the range.

Group. Listed under the family Iridaceae in the archetype table, and Kew describes it as “rhizomatous geophyte”. A group is taken only where Kew's description of the species agrees with the table's listing. The table gives no figure and no prose; the cold floor is the habitat's alone.

Climate across the habitat

Habitat months, southern hemisphere

Habitat climate of Trimezia martinicensis through the yearWarmest months May, June, July, August, September, October and November, mean daily high 27 °C; coldest months January and February, mean nightly low 22.4 °C; 1,904 mm of rain in the median year (the twelve monthly medians added). Medians across the range, from CHELSA; the extremes at the edge from NASA POWER. Habitat months, southern hemisphere.10°15°20°25°30°35°40°35.2° 99th-percentile day, NASA POWER18.1° lowest night in 44 years, NASA POWER°C · day and nightcold quarter0100200300400500mm rainDLI 31–41RH 64–68%JanFebMarAprMayJunJulAugSepOctNovDec
day night rain medians and 10th–90th percentile across 157 habitat cells, CHELSA cold quarter: the three months around the coldest month's mean nightly low extremes over 44 years at a typical spot in the range, from NASA POWER, marked at the edge, in no month DLI, mol/m²/dayRH %each on its own scale
Figures by month
JanFebMarAprMayJunJulAugSepOctNovDec
Day °C25 / 23–2925 / 23–2926 / 24–2926 / 24–2927 / 24–2927 / 24–2927 / 24–2927 / 24–3027 / 24–3027 / 24–3127 / 23–3026 / 23–29
Night °C22 / 16–2422 / 16–2423 / 16–2423 / 17–2524 / 17–2523 / 17–2623 / 17–2624 / 16–2624 / 17–2624 / 17–2623 / 17–2523 / 16–25
Rain mm107 / 52–28684 / 47–24588 / 35–280118 / 69–293159 / 105–365182 / 86–392198 / 88–321195 / 85–352204 / 76–423220 / 58–422207 / 52–318142 / 59–254
DLI32 / 29–3736 / 31–3940 / 31–4241 / 29–4338 / 28–4335 / 27–4236 / 28–4238 / 30–4137 / 30–3934 / 27–3931 / 26–3831 / 27–36
RH %65 / 61–7064 / 60–6965 / 60–6966 / 61–7067 / 63–7267 / 63–7367 / 62–7367 / 62–7367 / 62–7367 / 62–7368 / 62–7366 / 61–71

Records on both sides of the equator: the 62 cells at least 10° south of it have seasons six months apart and are left out, not combined into a year no place has. These figures are across the 157 cells that remain: the 97 at least 10° north and the 60 within 10° of the equator, which stay in either way.

How this section is made
Each figure is the median across the 157 grid cells holding the 234 in-range records, with the 10th–90th percentile span across those cells after the slash where it differs. A dash is a month one or more of those cells has no figure for in the grid (a variable CHELSA does not carry there), so no median is taken rather than one over fewer cells. Extremes and elevation were read at a typical spot in the range, cell 1706:2553 (4.675, -52.325). Over 44 years there: absolute minimum 18.1 °C, 1st-percentile night 20.4 °C, 99th-percentile day 35.2 °C. Normals: CHELSA V2.1 1981–2010 climatology, 0.05° cells (each the mean of ~36 1 km pixels). Across the range: median and 10th–90th percentile of each month across the 157 distinct grid cells holding 234 of the 302 in-range records on the northern side of the equator (97 cells poleward of 10° north, 62 poleward of 10° south: the two sides' seasons are not combined, and cells within 10° of the equator stay in); extremes and elevation at the typical cell 1706:2553 (its coldest month's mean nightly low nearest the median across cells); its position is the cell centre. Extremes: NASA POWER (MERRA-2) daily 1981–2024, cell 4.50_-52.500, lapse-corrected -20 m at 6.5 °C/km. Elevation: ETOPO 2022, 52 m (cell mean).

Natural habitat

Native range as published by WCVP; the marker is where the records are densest and decides nothing: the climate was read across the cells of the in-range records placed well enough to read one, not at the marker.
Openly licensed records inside the range, framed on where they fall.
NativeCosta Rica, Honduras, Leeward Is. AB Ant, Trinidad-Tobago, Venezuelan Antilles, Windward Is., Venezuela, Bolivia, Colombia, Brazil West-Central, Brazil Northeast, Brazil Southeast, Brazil North, Brazil South · introduced: Mauritius, Réunion, Malaya, Hawaii, Mexico Southeast, Jamaica, French Guiana · 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 marker-10.773, -37.356 · in the densest population, 189 records (33% of those in range)
Kew's description“rhizomatous geophyte” · “seasonally dry tropical” · quoted from WCVP, RBG Kew (CC BY 4.0); not derived here
Evidence usedThe map marker rests on all 573 georeferenced records inside the native range; the climate across the range on the 234 of them in the land cells it reads, of 302 placed to within 10 km; the map shows only the 435 openly licensed ones, which alone would put the marker 27 km away. 148 records outside the WCVP native range not used. 271 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 inside the densest 4° block of the 573 in-range records; it decides nothing. Records outside the native range, living specimens and records marked introduced are not used; which records count.

Photographs

Trimezia martinicensis, photograph 1did not loadTrimezia martinicensis, photograph 2did not loadTrimezia martinicensis, photograph 3did not loadTrimezia martinicensis, photograph 4did not loadTrimezia martinicensis, photograph 5did not loadTrimezia martinicensis, photograph 6did not load

Photographs: (c) Guillaume Delaitre, some rights reserved (CC BY) (5); (c) chrisdt, some rights reserved (CC BY).

Similar habitat climate The 6 nearest by mean daily high, mean nightly low and rain, month by month. How.

Pachystachys spicata Pachystachys spicata Cardinal's-guard Photo: CC BY, Matteo BellucciHeliconia caribaea Heliconia caribaea Lobsterclaw Photo: CC BY, Guillaume DelaitreOncidium altissimum Oncidium altissimum Wydler's dancing-lady orchid Photo: CC BY, chrisdtPitcairnia angustifolia Pitcairnia angustifolia Clapper Photo: CC BY, Guillaume DelaitreSelaginella flabellata Selaginella flabellata Fan spikemoss Photo: CC BY, Matteo BellucciPitcairnia spicata Pitcairnia spicata Bromeliaceae Photo: CC BY, Matteo Bellucci

Other Trimezia 11 in the reference

Trimezia candida Trimezia candida White walking iris Photo: CC0, author not statedTrimezia coerulea Trimezia coerulea Iridaceae Photo: CC0, author not statedTrimezia fosteriana Trimezia fosteriana Iridaceae Photo: CC0, Marcos QueirozTrimezia gracilis Trimezia gracilis Iridaceae Photo: CC BY, Victor Farjalla Pontes Trimezia humilis Iridaceae Trimezia liebmannii Trimezia liebmannii Iridaceae Photo: CC BY, Pedro Henrique Maloso RamosTrimezia longifolia Trimezia longifolia Iridaceae Photo: CC BY, Morten RossTrimezia northiana Trimezia northiana North's false flag Photo: CC0, author not statedTrimezia sabini Trimezia sabini Iridaceae Photo: CC BY, André Ribeiro CardosoTrimezia spathata Trimezia spathata Iridaceae Photo: CC BY, Carlos Otávio GussoniTrimezia steyermarkii Trimezia steyermarkii Yellow walking iris Photo: CC BY, Adam J. Searcy

Names & registers

Also known as Cipura martinicensis; Cipura semiaperta; Ferraria lurida; Iris martinicensis; Lansbergia caracasana and 20 more. (GBIF Backbone)

GBIFPOWOIPNIWFOWikidataWikipediaiNaturalist

The record

Family
Iridaceae
Described by
(Jacq.) Herb.
Native to
Costa Rica, Honduras, Leeward Is. AB Ant +11
Wild records
573 in range · 435 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; 48 records within 1 km of a botanic garden, herbarium or zoo left out (36 at a botanic garden or arboretum, 3 at a herbarium, 9 at a zoo; Wikidata's list)
Habitat climate climate answeredasked 2026-10-22
Daily extremes (NASA POWER) climate.extremes answeredasked 2026-10-22NASA POWER (MERRA-2) daily 1981–2024, cell 4.50_-52.500, lapse-corrected -20 m at 6.5 °C/km
Wikidata wikidata answeredasked 2026-10-22
Wikipedia wikipedia answeredasked 2026-10-22
iNaturalist photographs, wild inat.photos.wild answeredasked 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 answeredasked 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 90 datasets via GBIF.org; each carries its own licence.

Cultifolio

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