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Petractis clausa

Unknown

Overview

A detailed profile for this species is sourced from the IUCN Red List of Threatened Species as assessments become available.

Petractis clausa faces severe decline due to air pollution, particularly nitrogen deposition and sulfur compounds that alter the chemical composition of its substrate. Coastal development and quarrying activities destroy the specific limestone and calcareous rock surfaces this lichen requires. Climate change poses an additional threat through altered precipitation patterns and increased storm intensity affecting its specialized maritime cliff habitats.

Threat summary

Habitat

This crustose lichen grows exclusively on calcareous rocks and limestone surfaces in maritime environments, particularly on sea cliffs and coastal outcrops. It requires specific chemical conditions provided by calcium-rich substrates and is highly sensitive to air quality changes.

TERRESTRIAL· major

Other threatened species in Stictidaceae

CR

Cryptodiscus cladoniicola

Unknown
Petractis hypoleucaCR

Petractis hypoleuca

Unknown
CR

Nanostictis peltigerae

Unknown
VU

Thelopsis lichen

Thelopsis flaveola

Unknown

Frequently asked questions

Why is Petractis clausa classified as Endangered?
Petractis clausa is classified as Endangered — facing a very high risk of extinction in the wild — because population numbers are declining steeply and key habitats are under sustained pressure. Petractis clausa faces severe decline due to air pollution, particularly nitrogen deposition and sulfur compounds that alter the chemical composition of its substrate. Coastal development and quarrying activities destroy the specific limestone and calcareous rock surfaces this lichen requires. Climate change poses an additional threat through altered precipitation patterns and increased storm intensity affecting its specialized maritime cliff habitats.
Where does Petractis clausa live?
Petractis clausa occurs in across multiple regions. Country-level distribution data is sourced from the IUCN Red List and cross-referenced with GBIF occurrences.
What are the main threats to Petractis clausa?
The main threats to Petractis clausa are ai-1, ai-2, ai-3, and ai-4. The full IUCN-classified threat record for this species is detailed on the species page.

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