Stachytarpheta cayennensis (Rich.) Vahl
Blue snakeweed, Cayenne snakeweed, Dark-blue snakeweed, Bluetop, Blue porterweed, Nettle-leaf porterweed, Cayenne porterweed, Rattail, Blue rat's tail, Rough-leaf false vervain, Cayenne vervain, Nettleleaf vervain, Nettleleaf Velvetberry, False verbena, Joee, Cayenne porterweed, Cayenne porterweed; Verbena, Cayenne snakeweed
Every figure on this page is derived from public data by a stated rule and says its source; nothing here is written by a person or a model, except the Wikipedia passage, which is quoted and marked as such. How it is made.
Summary
Stachytarpheta cayennensis is a species of flowering plant in the verbena family known by many English language common names, including blue snakeweed, Cayenne snakeweed, dark-blue snakeweed, bluetop, nettle-leaf porterweed, rattail, rough-leaf false vervain, blue rat's tail, Brazilian tea, Cayenne vervain, false verbena, joee, nettleleaf velvetberry, and Cayenne porterweed. Names in other languages include honagasō (Japanese), gervão-urticante, piche de gato, rabo de zorro (Spanish), herbe à chenille, herbe bleue, queue de rat (French), ōi or ōwī (Hawaiian), sakura or ouchung (Chuukese), and tiāki (Māori). It is native to the Americas, from Mexico south through Central and South America to Argentina, as well as many islands of the Caribbean. It is known in many other parts of the world as an introduced species, including regions in Africa, India, Indonesia, Australia, Florida in the United States, and many Pacific Islands. More on Wikipedia ›
The opening of Wikipedia, “Stachytarpheta cayennensis”, CC BY-SA 4.0, quoted as written. Kept separate from everything derived here.
About the genus · Stachytarpheta
Stachytarpheta is a plant genus in the verbena family (Verbenaceae). The flowers are rich in nectar and popular with many butterflies, such as the South Asian crimson rose, Malabar banded swallowtail, and grass yellow. Hummingbirds, especially small species like Lophornis coquettes, Chlorostilbon emeralds, and Discosura thorntails, are especially attracted for nectar. More on Wikipedia ›
The opening of Wikipedia, “Stachytarpheta”, CC BY-SA 4.0, quoted as written.
At a glance
Also known as Abena cayennensis (Rich.) Hitchc.; Lippia cylindrica Scheele; Stachytarpha cayennensis (Rich.) Vahl; Stachytarpha dichotoma (Ruiz & Pav.) Vahl; Stachytarpha lactea Schauer and 37 more.
Cultivation
Its year Rain rule: no season, 70% of the rain takes 8 months (October to May at the habitat (not shifted)).
This species’ habitat figures, and what two fixed rules read from them.
The rain rule reads no season: 70% of the year's rain (1251 mm of 1665 mm) takes 8 months, October to May. Mean temperature moves 3.1 °C between the warmest and coldest month. Months are the habitat's, southern hemisphere; with a flat temperature curve there is no season to reverse, so they are not shifted for a collection elsewhere.
Read from the median year of CHELSA monthly rainfall and mean temperature across the envelope cells: 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 gives a season to reverse. A reading of the curves, not an observation of the plant.
Rain Habitat rain 1665 mm a year, wettest January at 175 mm, driest August at 88 mm (habitat calendar, southern hemisphere).
This species’ habitat figures, with their source.
1665 mm a year at the habitat, 1251 mm of it October to May. Wettest month January at 175 mm, driest August at 88 mm. Across the envelope cells the year's total runs 1192 mm to 2839 mm (10th to 90th percentile of each cell's own year) (median year across the envelope cells, CHELSA; habitat calendar, southern hemisphere).
CHELSA monthly precipitation, median year across the envelope cells. The rain that falls where the species is recorded; nothing about how the plant takes water.
Light Open sky over the habitat: 25 to 36 mol/m²/day.
This species’ habitat figures, with their source.
Open sky over the habitat: 25 to 36 mol/m²/day across the year (daily light integral, median year across the envelope cells, CHELSA; the lowest 10th-percentile month across the cells is 17, the highest 90th-percentile month 42).
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.
Warmth and air Cold floor 13.6 °C (1st-percentile habitat night, NASA POWER).
This species’ habitat figures, with their source.
Coldest: the 1st-percentile night over 44 years at the typical cell is 13.6 °C, the absolute minimum 10.9 °C, no frost in 44 years (NASA POWER daily minima). Warmest: the 99th-percentile day is 38.8 °C. Monthly means: coldest night 17.9 °C in July (across the envelope cells 11.2 °C to 23.3 °C), warmest day 28.3 °C in February (median year across the envelope cells, CHELSA). Cold floor: 13.6 °C, which is the 1st-percentile night over 44 years at the typical cell (NASA POWER).
NASA POWER daily minima and maxima 1981–2024 at the typical cell, lapse-corrected to its elevation; CHELSA monthly means, median year across the envelope cells, CHELSA. The cold floor is the figure named in its sentence. Not a measured survival limit for any plant in a pot.
Relative humidity at the habitat: 63 to 65% across the year (monthly means, median year across the envelope cells, CHELSA). A figure about the air, saying nothing about how the plant takes water.
CHELSA relative humidity, median year across the envelope cells.
The figures the cards read from are in Climate below, and where they came from in Natural habitat.
Climate across the habitat
Figures by month
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Day °C | 28 / 24–31 | 28 / 25–31 | 28 / 25–31 | 27 / 24–30 | 26 / 22–30 | 25 / 20–30 | 25 / 20–30 | 26 / 21–31 | 27 / 22–31 | 28 / 23–31 | 28 / 24–30 | 28 / 24–31 |
| Night °C | 22 / 17–24 | 22 / 17–24 | 21 / 17–24 | 20 / 16–24 | 19 / 14–24 | 19 / 12–24 | 18 / 11–23 | 18 / 12–24 | 19 / 14–24 | 20 / 15–24 | 21 / 16–24 | 21 / 17–24 |
| Rain mm | 175 / 53–325 | 157 / 49–296 | 156 / 49–305 | 145 / 61–306 | 132 / 43–321 | 115 / 17–345 | 105 / 11–294 | 88 / 17–291 | 106 / 41–297 | 146 / 55–283 | 167 / 52–261 | 173 / 56–301 |
| DLI | 35 / 27–42 | 36 / 29–39 | 34 / 29–39 | 30 / 25–41 | 27 / 20–38 | 25 / 17–35 | 27 / 19–37 | 31 / 24–38 | 33 / 27–39 | 35 / 28–39 | 35 / 26–40 | 34 / 26–42 |
| RH % | 64 / 59–70 | 64 / 60–70 | 64 / 60–70 | 64 / 60–70 | 65 / 58–71 | 65 / 57–71 | 64 / 54–71 | 63 / 52–70 | 63 / 54–71 | 64 / 57–71 | 64 / 59–71 | 65 / 59–70 |
Each figure is the median across the 836 grid cells holding the 942 in-range records, with the 10th–90th percentile span across those cells after the slash where it differs. Extremes and elevation were read at the typical cell 2065:2706 (-13.275, -44.675). Over 44 years there: absolute minimum 10.9 °C, 1st-percentile night 13.6 °C, 99th-percentile day 38.8 °C. Normals: CHELSA V2.1 1981–2010 climatology, 0.05° cells (each the mean of ~36 1 km pixels). Envelope: median and 10th–90th percentile of each month across the 836 distinct grid cells holding the 942 in-range records; extremes and elevation at the typical cell 2065:2706 (its coldest month's mean night nearest the median across cells); its position is the cell centre. Extremes: NASA POWER (MERRA-2) daily 1981–2024, cell -13.50_-44.375, lapse-corrected +45 m at 6.5 °C/km. Elevation: ETOPO 2022, 665 m (cell mean).
Natural habitat
Photographs
Photographs: (c) Victor Farjalla Pontes, some rights reserved (CC BY) (3); (c) Tobias Thrien, some rights reserved (CC BY); no rights reserved · CC0 (3); (c) Ben Machado, some rights reserved (CC BY).
Photographs: iNaturalist did not answer when this page was built; what is shown came from the sources that did.
Papers naming this species
Works whose title or abstract names Stachytarpheta cayennensis, most cited first, from OpenAlex (CC0). A mention, not a cultivation source: nothing on this page is drawn from them.
Related
Similar habitat climate the 6 species whose habitat climate is nearest this one's: mean day and night, month by month, and rain on a log scale, in calendar order, so a habitat with the same seasons six months out is far, not near. Nothing else counts: not range, not family.
Lippia alba Bush Tea
Schizolobium parahyba Brazilian Firetree
Centratherum punctatum Brazilian Buttonflower
Heliconia rostrata False Bird of ParadiseOther Stachytarpheta 2 in the reference
History & registers
Where this page came from built 2026-09-20 · dossier v2 · node
gbif.species answeredcarried from build of 2026-09-19 (offline re-derivation; the backbone was not asked)gbif.synonyms answeredcarried from build of 2026-09-19 (offline re-derivation; the backbone was not asked)gbif.vernacular answeredcarried from build of 2026-09-19 (offline re-derivation; the backbone was not asked)wcvp.distribution answeredgbif.occurrences answeredGBIF occurrence download https://doi.org/10.15468/dl.3h4zamclimate answeredwikidata answeredcarried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)wikipedia answeredcarried from build of 2026-09-19; this build: skippedinat.taxon not askedinat.photos.wild answeredcarried from build of 2026-09-19; this build: skippedinat.photos.cultivated nothing to reportcarried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)commons nothing to reportcarried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)gbif.media answeredopenalex answeredcarried from build of 2026-09-19; this build: skippedEvery upstream is recorded as having answered, reported nothing, or refused. Only “nothing to report” is ever shown as an absence. Records came from 216 datasets via GBIF.org; each carries its own licence.








