Lathraea squamariaL.

common toothworttoothwort

WFO wfo-0000445615 Accepted WFO 2026-06 8 photographs CC0 / CC BY

Plate 1 figs. a–h · 8 separate observations

Lathraea squamaria, photographed by Екатерина Кропочева
fig. a Екатерина Кропочева, CC BY 4.0 / 2022-05-28 / obs. 201985263

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 40 botanical countries

Regions where Lathraea squamaria is native: Iran, Lebanon-Syria, North Caucasus, Transcaucasus, Türkiye, West Siberia, East Himalaya, Pakistan, West Himalaya, Albania, Austria, Baltic States, Belarus, Belgium, Bulgaria, Central European Russia, Czechia-Slovakia, Denmark, East European Russia, Finland, France, Germany, Great Britain, Greece, Hungary, Ireland, Italy, Krym, Netherlands, Northwest European Russia, Norway, NW. Balkan Pen., Poland, Romania, Sicilia, Spain, Sweden, Switzerland, Türkiye-in-Europe, Ukraine IranLebanon-SyriaNorth CaucasusTranscaucasusTürkiyeWest SiberiaEast HimalayaPakistanWest HimalayaAlbaniaAustriaBaltic StatesBelarusBelgiumBulgariaCentral European RussiaCzechia-SlovakiaDenmarkEast European RussiaFinlandFranceGermanyGreeceHungaryIrelandItalyKrymNetherlandsNorthwest European RussiaNorwayNW. Balkan Pen.PolandRomaniaSiciliaSpainSwedenSwitzerlandTürkiye-in-EuropeUkraine
Native distribution of Lathraea squamaria, 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.
RegionTDWG codeContinent
Albania ALB EUROPE
Austria AUT
Baltic States BLT
Belarus BLR
Belgium BGM
Bulgaria BUL
Central European Russia RUC
Czechia-Slovakia CZE
Denmark DEN
East European Russia RUE
Finland FIN
France FRA
Germany GER
Great Britain GRB
Greece GRC
Hungary HUN
Ireland IRE
Italy ITA
Krym KRY
Netherlands NET
Northwest European Russia RUW
Norway NOR
NW. Balkan Pen. YUG
Poland POL
Romania ROM
Sicilia SIC
Spain SPA
Sweden SWE
Switzerland SWI
Türkiye-in-Europe TUE
Ukraine UKR
Iran IRN ASIA-TEMPERATE
Lebanon-Syria LBS
North Caucasus NCS
Transcaucasus TCS
Türkiye TUR
West Siberia WSB
East Himalaya EHM ASIA-TROPICAL
Pakistan PAK
West Himalaya WHM

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 1,062 in flower of 1,195 examined

Proportion of examined Lathraea squamaria in flower, by month
Month In flower Examined Share 95% interval
Jan 1 3 too few examined
Feb 29 39 74% 59% to 85%
Mar 323 339 95% 92% to 97%
Apr 517 534 97% 95% to 98%
May 183 219 84% 78% to 88%
Jun 7 52 13% 7% to 25%
Jul 0 1 too few examined
Aug 0 0 too few examined
Sep 0 3 too few examined
Oct 0 2 too few examined
Nov 2 3 too few examined
Dec 0 0 too few examined

Peak flowering in Apr. Each bar is the share of Lathraea squamaria 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. 1,062 of 1,195 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 7 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 1,918 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -11.8 °C -4.7 °C 1.5 °C
Warmest month, mean daily high 18.8 °C 23.0 °C 26.2 °C
Annual rainfall 558 mm 741 mm 1,492 mm
Rainfall in the driest quarter 88 mm 122 mm 285 mm

It is found where winters bring hard frost. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 1,918 research-grade observations of Lathraea squamaria 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 7 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.

  • Anblatum tournefortii G.Don
  • Clandestina squamaria (L.) Legrand
  • Lathraea simplex Gray
  • Lathraea squamaria var. erecta K.Koch
  • Lathraea staminea Janka
  • Lathraea tatrica (Hadač) Landolt
  • Squamaria orobanche Scop.

Sourcesevery claim on this page

  1. World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
  2. iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
  3. Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
  4. 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.