• Proposed
  • Under Assessment
  • Preliminary Assessed
  • Assessed
  • ENPublished

Anzia centrifuga Haugan

Search for another species...

Scientific name
Anzia centrifuga
Common names
IUCN Specialist Group
Assessment status
Assessment date
IUCN Red List Category
IUCN Red List Criteria
Sparrius, L., Aptroot, A., Sipman, H., Pérez-Vargas, I., Matos, P., Gerlach, A. & Vervoort, M.
Allen, J.

Assessment Notes

The content on this page is fetched from The IUCN Red List of Threatened Species: https://www.iucnredlist.org/species/64081145/205629065


Anzia centrifuga is a rock-dwelling species that is narrowly endemic to Porto Santo in the Madeira archipelago where it occurs at five sites. There are only 100-150 individuals of this species (Sparrius et al. 2017), thus it is Endangered under criterion D.

Taxonomic notes

This lichen species is easy to recognize in the field by lichenologists. The species' taxonomy is well defined and it is the only species of this genus in the Madeira archipelago. The species grows over rocks and adnate to loosely attached to the substrate. The thallus is orbicular up to 30 cm in diameter, dying at the center of the thallus; the colour is pale grey. The thallus has numerous apothecia. Lobes are 1-2 mm wide, dichotomously branched, more or less overlapping, lobe tips showing calcium oxalate deposits. The medulla has a chondroid axis. The lower side is with a black, foam-like layer of short, interwoven rhizines characteristic of this genus. Secondary metabolites include atranorin and several unknown terpenoids.

Geographic range

This species occurs only at five sites on Porto Santo (Madeira archipelago, Portugal).

Population and Trends

The population size is estimated to be 100-150 individuals based on an extensive field survey in 2016 on all parts of the island with suitable habitat for the species, which are mainly basalt rockfaces at higher elevations. The method are described in detail by Sparrius et al. (2017).

Population Trend: unknown

Habitat and Ecology

Anzia centrifuga grows on well illuminated rocks together with various crustose lichens.


This species occurs only at five sites on one small island. Sites could be lost due to wildfire or trampling (rock climbing, tourism), if tourism development occurred in their vicinity. The past impact of these threats has not been documented. Most sites are at places at higher elevations and at some distance from paths and roads.

Conservation Actions

No conservation plan is available. It is advised to repeat the field survey by 2035 in order to observe any trends.

Source and Citation

Sparrius, L., Aptroot, A., Sipman, H., Pérez-Vargas, I., Matos, P., Gerlach, A. & Vervoort, M. 2021. Anzia centrifuga. The IUCN Red List of Threatened Species 2021: e.T64081145A205629065. https://dx.doi.org/10.2305/IUCN.UK.2021-3.RLTS.T64081145A205629065.en .Accessed on 31 January 2022

Country occurrence