Atlantic Gray Seal vs Common Tarcrust

Halichoerus grypus compared with Diatrype stigma

Key Differences

Atlantic Gray Seal is Vulnerable while Common Tarcrust is Not Evaluated.

Taxonomic Classification

Rank	Atlantic Gray Seal	Common Tarcrust
Kingdom	Animalia (Animals)	Fungi (Fungi)
Phylum	Chordata (Chordates)	Ascomycota (Sac Fungi)
Class	Mammalia (Mammals)	Sordariomycetes (Sordariomycetes)
Order	Pinnipedia (Seals & Sea Lions)	Xylariales (Xylariales)
Family	Phocidae (True Seals)	Diatrypaceae
Genus	Halichoerus	Diatrype
Species	Halichoerus grypus	Diatrype stigma

Conservation Status

Atlantic Gray Seal

VU — Vulnerable

Common Tarcrust

NE — Not Evaluated

Physical Characteristics

Attribute	Atlantic Gray Seal	Common Tarcrust
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Atlantic Gray Seal

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Range

Distributed across Belgium, Denmark, Norway, Portugal, and Sweden. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Common Tarcrust

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Belgium, Denmark, Norway, Portugal, and Sweden.

Atlantic Gray Seal

The Atlantic Gray Seal (Halichoerus grypus) is a species in the genus Halichoerus. It is currently classified as Vulnerable on the IUCN Red List. Typically found in diverse terrestrial and aquatic ecosystems.

Common Tarcrust

<em>Diatrype stigma</em>, the common tarcrust, is a saprotrophic fungus in the family Diatrypaceae, found across Belgium, Denmark, Norway, Portugal, and Sweden, as well as more broadly in Europe and temperate regions globally. It grows as a crust-like, charcoal-black stromata on the dead bark and branches of deciduous hardwoods, particularly hazel, beech, and alder. The fruiting bodies are typically flat to slightly raised, dark gray to black patches that contain numerous embedded perithecia in which ascospores are produced. This fungus plays an important ecological role as a decomposer, breaking down dead woody material and recycling nutrients in forest ecosystems. It is Not Evaluated on the IUCN Red List; given its broad distribution on common substrates, it is generally considered widespread. The species reproduces via wind-dispersed ascospores released from the perithecia. Diet, as a saprotrophic organism, consists of dead organic woody matter. Biological traits such as colony growth rates, spore output, and longevity remain poorly documented in standardized quantitative assessments.