Common Least Skipper vs Common Tarcrust

Ancyloxypha numitor compared with Diatrype stigma

Key Differences

• Common Least Skipper is Least Concern while Common Tarcrust is Not Evaluated.

Taxonomic Classification

Rank	Common Least Skipper	Common Tarcrust
Kingdom	Animalia (Animals)	Fungi (Fungi)
Phylum	Arthropoda (Arthropods)	Ascomycota (Sac Fungi)
Class	Insecta (Insects)	Sordariomycetes (Sordariomycetes)
Order	Lepidoptera (Butterflies & Moths)	Xylariales (Xylariales)
Family	Hesperiidae	Diatrypaceae
Genus	Ancyloxypha	Diatrype
Species	Ancyloxypha numitor	Diatrype stigma

Conservation Status

Common Least Skipper

LC — Least Concern

Common Tarcrust

NE — Not Evaluated

Physical Characteristics

Attribute	Common Least Skipper	Common Tarcrust
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Least Skipper

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Canada and United States.

Common Tarcrust

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

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

Common Least Skipper

The Common Least Skipper (<em>Ancyloxypha numitor</em>) is a small butterfly in the family Hesperiidae, classified as Least Concern on the IUCN Red List. It is native to Canada and the United States, where it typically inhabits virtually all terrestrial and freshwater habitats within its range, showing a particular affinity for moist, grassy areas near water. The species is among the smallest skippers in North America, characterized by orange and brown wing coloration and a rapid, low-flying flight pattern close to vegetation. Adults typically nectar on small flowers while larvae feed on grasses, particularly those in wet meadows, marshes, stream margins, and disturbed grassy areas. The Common Least Skipper is frequently observed in wetland margins, wet prairies, and roadsides with rank grass growth. Its wide distribution across North America and habitat generalism across moist grassland and wetland types support its stable population and Least Concern conservation status. Biological traits of this species remain poorly documented in the scientific literature.

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.