Alder leaf beetle vs Common Tarcrust

Agelastica alni compared with Diatrype stigma

Key Differences

Alder leaf beetle is Least Concern while Common Tarcrust is Not Evaluated.

Taxonomic Classification

Rank	Alder leaf beetle	Common Tarcrust
Kingdom	Animalia (Animals)	Fungi (Fungi)
Phylum	Arthropoda (Arthropods)	Ascomycota (Sac Fungi)
Class	Insecta (Insects)	Sordariomycetes (Sordariomycetes)
Order	Coleoptera (Beetles)	Xylariales (Xylariales)
Family	Chrysomelidae	Diatrypaceae
Genus	Agelastica	Diatrype
Species	Agelastica alni	Diatrype stigma

Conservation Status

Alder leaf beetle

LC — Least Concern

Common Tarcrust

NE — Not Evaluated

Physical Characteristics

Attribute	Alder leaf beetle	Common Tarcrust
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Alder leaf beetle

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Belgium, Denmark, Norway, Sweden, and United States.

Common Tarcrust

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

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

Alder leaf beetle

The Alder leaf beetle (Agelastica alni) is a species in the genus Agelastica. It is currently classified as Least Concern on the IUCN Red List. Typically found in virtually all terrestrial and freshwater habitats.

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.