Carduncellus caeruleus

Plate 1 figs. a–h · 8 separate observations

Carduncellus caeruleus, photographed by Mehdi Chetibi — fig. c Mehdi Chetibi, CC BY 4.0 / obs. 132394945

Carduncellus caeruleus, photographed by Duarte Frade — fig. d Duarte Frade, CC BY 4.0 / obs. 103987906

Carduncellus caeruleus, photographed by Aissa Djamel Filali — fig. e Aissa Djamel Filali, CC BY-SA 4.0 / obs. 73986315

Carduncellus caeruleus, photographed by Ivo Rosa — fig. f Ivo Rosa, CC BY 4.0 / obs. 184192294

Carduncellus caeruleus, photographed by Ricardo Lima — fig. g Ricardo Lima, CC0 1.0 / obs. 128036237

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

Native range 21 botanical countries

Native distribution of Carduncellus caeruleus, after Kew’s World Checklist of Vascular Plants. Introduced, extinct and doubtful records are excluded, so this is where the plant is from, not everywhere it now grows. Regions too small to draw at this scale are marked with a dot.

Region	TDWG code	Continent
Baleares	BAL	EUROPE
Corse	COR
France	FRA
Great Britain	GRB
Greece	GRC
Italy	ITA
Kriti	KRI
Portugal	POR
Sardegna	SAR
Sicilia	SIC
Spain	SPA
Algeria	ALG	AFRICA
Canary Is.	CNY
Libya	LBY
Madeira	MDR
Morocco	MOR
Tunisia	TUN
Cyprus	CYP	ASIA-TEMPERATE
East Aegean Is.	EAI
Lebanon-Syria	LBS
Türkiye	TUR

Not drawn on the map: Great Britain. We hold no public-domain boundary for this region, so it is listed rather than guessed at.

Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.

Flowering 63 in flower of 77 examined

100%

91%

44%

Proportion of examined Carduncellus caeruleus in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	0	2	too few examined
Feb	0	1	too few examined
Mar	2	2	too few examined
Apr	25	25	100%	87% to 100%
May	32	35	91%	78% to 97%
Jun	4	9	44%	19% to 73%
Jul	0	2	too few examined
Aug	0	0	too few examined
Sep	0	1	too few examined
Oct	0	0	too few examined
Nov	0	0	too few examined
Dec	0	0	too few examined

Peak flowering in Apr. Each bar is the share of Carduncellus caeruleus observations in which someone actually recorded the reproductive state and found the plant in flower, not the raw number of flowering records. That distinction matters: people observe plants far more in spring than in winter, so a bare count of flowering records partly measures when people go outside. Dividing by the number examined removes that. 63 of 77 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 9 months have fewer than 5 examined observations, so no proportion is drawn for them. This is still a global aggregate and not a forecast for your garden: the same species flowers on different dates in different hemispheres. Where a species has fewer than 30 flowering records we do not draw this chart at all. Computed from 10.15468/dl.cgje2x.

Where it actually grows measured, from 379 observations

Condition	5th percentile	Median	95th percentile
Coldest month, mean daily low	3.2 °C	8.5 °C	11.4 °C
Warmest month, mean daily high	21.1 °C	26.7 °C	34.6 °C
Annual rainfall	547 mm	712 mm	951 mm
Rainfall in the driest quarter	13 mm	24 mm	66 mm

It is found where winters are cool but frost is light or absent. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 379 research-grade observations of Carduncellus caeruleus that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.

This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one. Climate from CHELSA V2.1 (Karger et al. 2017); occurrences from 10.15468/dl.cgje2x.

Also published as 19 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

Carduncellus caeruleus (L.) C.Presl
Carduncellus caeruleus (L.) DC.
Carduncellus caeruleus subsp. caeruleus
Carduncellus caeruleus subsp. tingitanus (L.) Rivas Goday & Rivas Mart.
Carduncellus caeruleus var. caeruleus
Carduncellus coeruleus subsp. coeruleus
Carduncellus tingitanus DC. ex Duby
Carduncellus tingitanus (L.) C.Presl
Carthamodes coeruleum Kuntze
Carthamus caeruleus L.
Carthamus caeruleus var. caeruleus
Carthamus caeruleus var. tingitanus (L.) Ball
Carthamus carlinoides (Pomel) Batt.
Carthamus carolinensis Hort.Trian. ex Buc'hoz
Carthamus tingitanus L.
Centaurea tingitana L.
Lamottea caerulea var. caerulea
Lamottea caerulea var. centaureoides Pomel
Lamottea caerulea var. montana Pomel

Sourcesevery claim on this page

World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.

We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.