Epithelantha micromeris (Engelm.) F.A.C.Weber
Button Cactus, Mulatto, Pingpong Ball Cactus, Tapone
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
Epithelantha micromeris is a button cactus in the genus Epithelantha, found in Arizona, New Mexico, Texas and northeast Mexico. It is characterized by its white-grey spines growing on a globular shaped stem. The density of its white spines give it the illusion of being completely grey, making it very difficult to see the green color beneath. It grows to be 1–5 cm tall, and roughly 2–4 cm in diameter. More on Wikipedia ›
The opening of Wikipedia, “Epithelantha micromeris”, CC BY-SA 4.0, quoted as written. Kept separate from everything derived here.
About the genus · Epithelantha
Epithelantha is a genus of cactus that is native to north-eastern Mexico, and the south-western United States. There are ten species recognised in the genus Epithelantha. The name Epithelantha refers to the flower position near the apex of the tubercles.
Text from Wikipedia, “Epithelantha”, CC BY-SA 4.0, quoted as written.
At a glance
Also known as Cactus leucodasys Kuntze; Cactus leucodictius (Link ex Otto & Dietr.) Kuntze; Cactus micromeris (Engelm.) Kuntze; Cephalomamillaria micromeris (Engelm.) Fric; Echinocactus micromeris F.A.C.Weber and 15 more.
Cultivation
Grouped as a cactus or succulent by the genus Epithelantha, which is reliably one kind of plant (archetype table). The table holds no figure for this group, which spans too much for one minimum; the cold floor is the habitat's alone, and no prose comes from the table.
Its year Rain rule: a summer growing season, May to October in the northern hemisphere (May to October at the habitat, northern).
This species’ habitat figures, and what two fixed rules read from them.
The rain rule reads a summer growing season: 70% of the year's rain (268 mm of 351 mm) falls in May to October, warmer than the year (wet-season mean 24.0 °C against a yearly mean of 19.9 °C). Months are the habitat's, northern hemisphere; shifted six months for a southern-hemisphere collection: November to April.
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 351 mm a year, wettest July at 58 mm, driest March at 10 mm (habitat calendar, northern hemisphere).
This species’ habitat figures, with their source.
351 mm a year at the habitat, 268 mm of it May to October. Wettest month July at 58 mm, driest March at 10 mm. Across the envelope cells the year's total runs 245 mm to 565 mm (10th to 90th percentile of each cell's own year) (median year across the envelope cells, CHELSA; habitat calendar, northern 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 47 mol/m²/day.
This species’ habitat figures, with their source.
Open sky over the habitat: 25 to 47 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 21, the highest 90th-percentile month 51).
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 -1.3 °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 -1.3 °C, the absolute minimum -9.3 °C, about 7 frost nights a year (NASA POWER daily minima). Warmest: the 99th-percentile day is 39.7 °C. Monthly means: coldest night 6.9 °C in January (across the envelope cells 1.0 °C to 8.3 °C), warmest day 31.5 °C in June (median year across the envelope cells, CHELSA). Cold floor: -1.3 °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: 47 to 58% 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 | 20 / 14–21 | 22 / 17–24 | 25 / 21–27 | 28 / 25–31 | 30 / 27–33 | 32 / 28–34 | 31 / 27–33 | 31 / 27–33 | 28 / 24–30 | 25 / 22–28 | 23 / 18–25 | 20 / 13–22 |
| Night °C | 7 / 1–8 | 9 / 3–10 | 11 / 6–13 | 14 / 10–16 | 17 / 14–19 | 20 / 17–22 | 20 / 16–22 | 20 / 16–22 | 18 / 15–20 | 14 / 11–16 | 11 / 6–12 | 8 / 1–9 |
| Rain mm | 18 / 12–25 | 12 / 7–18 | 10 / 6–19 | 19 / 10–38 | 31 / 18–62 | 40 / 24–67 | 58 / 40–88 | 54 / 33–83 | 54 / 35–100 | 31 / 21–52 | 10 / 8–18 | 14 / 10–20 |
| DLI | 26 / 24–28 | 32 / 30–34 | 40 / 37–43 | 45 / 41–48 | 47 / 43–51 | 46 / 43–51 | 44 / 43–47 | 42 / 41–44 | 37 / 34–39 | 33 / 30–35 | 28 / 25–30 | 25 / 21–26 |
| RH % | 51 / 48–56 | 50 / 46–55 | 47 / 42–54 | 47 / 38–55 | 50 / 40–58 | 53 / 43–59 | 54 / 48–58 | 54 / 50–59 | 58 / 50–63 | 56 / 48–60 | 52 / 47–57 | 51 / 49–56 |
Each figure is the median across the 55 grid cells holding the 58 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 1265:1556 (26.725, -102.175). Over 44 years there: absolute minimum -9.3 °C, 1st-percentile night -1.3 °C, 99th-percentile day 39.7 °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 55 distinct grid cells holding the 58 in-range records; extremes and elevation at the typical cell 1265:1556 (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 26.50_-101.875, lapse-corrected -179 m at 6.5 °C/km. Elevation: ETOPO 2022, 1061 m (cell mean).
Natural habitat
Photographs
Photographs: (c) Trevor Harding, some rights reserved (CC BY) (3); (c) Jo Roberts, some rights reserved (CC BY) (3); (c) Karla M. Benítez, some rights reserved (CC BY); (c) CK2AZ, some rights reserved (CC BY).
Photographs: iNaturalist and Wikimedia Commons 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 Epithelantha micromeris, 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.
Euphorbia antisyphilitica candelilla
Agave victoriae-reginae Queen Victoria Agave
Buddleja marrubiifolia Woolly Butterflybush
Epithelantha cryptica Cactaceae
Astrophytum capricorne bishop's-cap
Mammillaria pottsii Pott's Nipple-cactusOther Epithelantha 9 in the reference
Epithelantha bokei Boke's button cactus Epithelantha cryptica Cactaceae
Epithelantha greggii Cactaceae
Epithelantha ilariae Cactaceae
Epithelantha pachyrhiza Cactaceae Epithelantha polycephala Cactaceae
Epithelantha potosina Cactaceae
Epithelantha pulchra Cactaceae
Epithelantha spinosior Cactaceae 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 not askedcarried 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 20 datasets via GBIF.org; each carries its own licence.