Laennecia filaginoidesDC.

Trans-Pecos horseweed

WFO wfo-0000026913 Accepted WFO 2026-06 8 photographs CC BY

Plate 1 figs. a–h · 2 observations

This species has been photographed under an open licence only 2 times, so some figures below are different views of the same plant, taken on the same day, rather than different individuals. They are usually different parts of it: the leaf, the flower, the bark.

Laennecia filaginoides, photographed by Carlos Martorell
fig. a Carlos Martorell, CC BY 4.0 / 2016-09-22 / obs. 9618666
Laennecia filaginoides, photographed by Carlos Martorell
fig. b Carlos Martorell, CC BY 4.0 / obs. 9618667
Laennecia filaginoides, photographed by Carlos Martorell
fig. c Carlos Martorell, CC BY 4.0 / obs. 518884
Laennecia filaginoides, photographed by Carlos Martorell
fig. d Carlos Martorell, CC BY 4.0 / obs. 9618668
Laennecia filaginoides, photographed by Carlos Martorell
fig. e Carlos Martorell, CC BY 4.0 / obs. 9618669
Laennecia filaginoides, photographed by Carlos Martorell
fig. f Carlos Martorell, CC BY 4.0 / obs. 518885
Laennecia filaginoides, photographed by Carlos Martorell
fig. g Carlos Martorell, CC BY 4.0 / obs. 518886
Laennecia filaginoides, photographed by Carlos Martorell
fig. h Carlos Martorell, CC BY 4.0 / obs. 518883

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 12 botanical countries

Regions where Laennecia filaginoides is native: Mexico Central, Mexico Gulf, Mexico Northeast, Mexico Northwest, Mexico Southeast, Mexico Southwest, Texas, Colombia, Ecuador, Guatemala, Peru, Venezuela Mexico CentralMexico GulfMexico NortheastMexico NorthwestMexico SoutheastMexico SouthwestTexasColombiaEcuadorGuatemalaPeruVenezuela
Native distribution of Laennecia filaginoides, 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
Mexico Central MXC NORTHERN AMERICA
Mexico Gulf MXG
Mexico Northeast MXE
Mexico Northwest MXN
Mexico Southeast MXT
Mexico Southwest MXS
Texas TEX
Colombia CLM SOUTHERN AMERICA
Ecuador ECU
Guatemala GUA
Peru PER
Venezuela VEN

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.

Also published as 2 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.

  • Conyza filaginoides (DC.) Hieron.
  • Laennecia pinnatifida Turcz.

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.