Gustavo Puente, CC0, iNaturalist via GBIF · observed growing wild

Gymnocalycium schroederianum Osten

Cactaceae

Climate known 17 photographs Cactus or succulent

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

Gymnocalycium schroederianum is a species of Gymnocalycium from Argentina and Uruguay.

Text from Wikipedia, “Gymnocalycium schroederianum”, CC BY-SA 4.0, quoted as written. Kept separate from everything derived here.

About the genus · Gymnocalycium

Gymnocalycium, commonly called chin cactus, is a genus of about 70 South American species of cactus. The genus name Gymnocalycium refers to the flower buds bearing no hair or spines. In a 2023 classification of the tribe Cereeae, it was placed as the only genus in the subtribe Gymnocalyciinae, having formerly been placed in the subtribe Rebutiinae.

Text from Wikipedia, “Gymnocalycium”, CC BY-SA 4.0, quoted as written.

Family

Cactaceae

Described by

Osten

Native to

Argentina Northeast, Uruguay

Wild records

34 in range· 13 open

At a glance

Warmest month

31°C

Jan, mean day; nights 21 °C (CHELSA)

Rain

1231mm/yr

12 wet months · peak Apr 149 mm (CHELSA)

Light

16–46DLI

mol/m²/day, winter to summer, open sky (CHELSA shortwave)

In short condensed by rule from the cultivation cards · not written by a person

Grouped as a cactus or succulent by the genus Gymnocalycium, which is reliably one kind of plant (archetype table). Rain rule: a summer growing season, April to October in the northern hemisphere (October to April at the habitat, southern). Habitat rain 1231 mm a year, wettest April at 149 mm, driest July at 44 mm (habitat calendar, southern hemisphere). Open sky over the habitat: 16 to 46 mol/m²/day. Cold floor -0.5 °C (1st-percentile habitat night, NASA POWER).

Each sentence is one card's own one-line form, written by the same rule as the card (Its year, Rain, Light, Temperature); the note cannot say what a card does not. Months are given for the northern hemisphere (set your site in Settings to change this), and the habitat's own alongside. The cards · the figures.

Also known as Gymnocalycium erolesii Neuhuber & C.A.L.Bercht; Gymnocalycium hyptiacanthum subsp. paucicostatum (R.Kiesling) Papsch; Gymnocalycium hyptiacanthum subsp. schroederianum (Osten) Papsch; Gymnocalycium platense subsp. paucicostatum (R.Kiesling) Papsch; Gymnocalycium platense subsp. schroederianum (Osten) Papsch and 4 more.

Cultivation

Grouped as a cactus or succulent by the genus Gymnocalycium, 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, April to October in the northern hemisphere (October to April at the habitat, southern).

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 (917 mm of 1231 mm) falls in October to April, warmer than the year (wet-season mean 22.6 °C against a yearly mean of 19.1 °C). Months are the habitat's, southern hemisphere; shifted six months for a northern-hemisphere collection: April to October.

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 1231 mm a year, wettest April at 149 mm, driest July at 44 mm (habitat calendar, southern hemisphere).

This species’ habitat figures, with their source.

1231 mm a year at the habitat, 917 mm of it October to April. Wettest month April at 149 mm, driest July at 44 mm. Across the envelope cells the year's total runs 1091 mm to 1321 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: 16 to 46 mol/m²/day.

This species’ habitat figures, with their source.

Open sky over the habitat: 16 to 46 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 14, the highest 90th-percentile month 47).

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 -0.5 °C (1st-percentile habitat night, NASA POWER).

This species’ habitat figures, with their source.

Temperature

Coldest: the 1st-percentile night over 44 years at the typical cell is -0.5 °C, the absolute minimum -4.2 °C, about 5 frost nights a year (NASA POWER daily minima). Warmest: the 99th-percentile day is 40.4 °C. Monthly means: coldest night 8.7 °C in July (across the envelope cells 6.1 °C to 9.7 °C), warmest day 30.7 °C in January (median year across the envelope cells, CHELSA). Cold floor: -0.5 °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.

Humidity

Relative humidity at the habitat: 56 to 62% 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

day night rain 10th–90th percentile across 18 habitat cells cold quarter: the three months around the coldest night extremes over 44 years at the typical cell, marked at the edge: undated DLI, mol/m²/dayRH %each on its own scale

Figures by month

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Day °C	31 / 29–31	29 / 28–30	28 / 26–28	24 / 22–25	20 / 18–21	17 / 15–18	17 / 14–18	20 / 17–21	21 / 19–23	25 / 22–26	27 / 25–28	29 / 28–30
Night °C	21 / 19–22	20 / 18–21	19 / 17–20	15 / 13–16	12 / 10–13	10 / 7–11	9 / 6–10	10 / 7–11	11 / 9–13	14 / 12–16	17 / 15–18	19 / 17–20
Rain mm	124 / 116–141	134 / 118–144	142 / 122–162	149 / 103–178	93 / 59–102	61 / 38–77	44 / 31–58	45 / 31–59	71 / 58–86	118 / 109–132	131 / 104–150	119 / 106–137
DLI	45 / 44–46	39 / 39–40	33 / 32–33	23 / 23–24	19 / 17–19	16 / 14–16	18 / 16–19	23 / 22–24	29 / 29–30	36 / 36–37	43 / 42–44	46 / 45–47
RH %	56 / 55–57	58 / 57–59	59 / 58–60	61 / 60–61	61 / 60–62	62 / 62–63	61 / 60–61	59 / 58–60	58 / 57–59	57 / 57–59	56 / 56–57	56 / 54–57

Each figure is the median across the 18 grid cells holding the 31 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 2417:2409 (-30.875, -59.525). Over 44 years there: absolute minimum -4.2 °C, 1st-percentile night -0.5 °C, 99th-percentile day 40.4 °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 18 distinct grid cells holding the 31 in-range records; extremes and elevation at the typical cell 2417:2409 (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 -31.00_-59.375, lapse-corrected -8 m at 6.5 °C/km. Elevation: ETOPO 2022, 48 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 every in-range record's cell, not at the marker.

Openly licensed records inside the range, framed on where they fall.

NativeArgentina Northeast, Uruguay

Kew's description“succulent subshrub” · “subtropical”· quoted from WCVP, RBG Kew (CC BY 4.0); not derived here

Map marker-32.884, -58.047 · in the densest population, 24 records (71% of those in range)

Evidence usedThe map marker and the climate envelope rest on all 34 georeferenced records inside the native range; the map shows only the 13 openly licensed ones, which alone would put the marker 48 km away. 1 record outside the range (gardens, roadsides, misidentifications) ignored. 3 in-range records are placed to worse than 10 km and stay on the map but off the climate.

The map markerthe map marker: the openly licensed record nearest the middle of the densest 1° population of the 34 in-range records; it decides nothing.

Photographs

Photographs: Gustavo Puente, CC0, iNaturalist via GBIF (3); Agustina Collazo, CC BY, iNaturalist via GBIF (2); Ivan Grela, CC BY, iNaturalist via GBIF (3).

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 Gymnocalycium schroederianum, most cited first, from OpenAlex (CC0). A mention, not a cultivation source: nothing on this page is drawn from them.

Gymnocalycium schroederianum Osten. In: Marchesi E., Mailhos A. & Bonifacino J.M. (Eds.). Flora Uruguaya: Flora Vascular del Uruguay. ISSN 3121-2050, V. 1.0.