Common harp ground beetle vs Common Oak Fern

Amara communis compared with Gymnocarpium dryopteris

Key Differences

• Common harp ground beetle is Least Concern while Common Oak Fern is Critically Endangered.

Taxonomic Classification

Rank	Common harp ground beetle	Common Oak Fern
Kingdom	Animalia (Animals)	Plantae (Plants)
Phylum	Arthropoda (Arthropods)	Tracheophyta
Class	Insecta (Insects)	Polypodiopsida (Polypodiopsida)
Order	Coleoptera (Beetles)	Polypodiales (Polypodiales)
Family	Carabidae	Cystopteridaceae
Genus	Amara	Gymnocarpium
Species	Amara communis	Gymnocarpium dryopteris

Conservation Status

Common harp ground beetle

LC — Least Concern

Common Oak Fern

CR — Critically Endangered

Physical Characteristics

Attribute	Common harp ground beetle	Common Oak Fern
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common harp ground beetle

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Found across Europe (5 countries) and North America (Canada, United States).

Common Oak Fern

Habitat

Found across multiple habitat types including temperate broadleaf and mixed forests, temperate coniferous forests, and boreal forests and taiga, among 4 distinct biome types within the Palearctic biogeographic realm. Populations are also found in montane and highland environments at higher elevations.

Range

Found across Europe (6 countries) and North America (Canada, United States). Currently classified as Critically Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Common harp ground beetle

The common harp ground beetle, <em>Amara communis</em>, is an insect belonging to the order Coleoptera, family Carabidae, the ground beetles. This species is distributed across Europe and North America, indicating a wide Holarctic range. Ground beetles of the genus Amara are typically found in a variety of terrestrial habitats including grasslands, agricultural fields, woodland margins, and disturbed areas. Members of this genus are generally omnivorous or seed-feeding, and some are known to consume weed seeds, giving them potential ecological significance in agroecosystems. <em>Amara communis</em> is assessed as Least Concern on the IUCN Red List, reflecting stable populations across its range. No dietary information has been provided specifically for this species in current records. Biological traits of this species remain poorly documented in the scientific literature.

Common Oak Fern

<em>Gymnocarpium dryopteris</em>, the common oak fern, is a delicate terrestrial fern in the family Cystopteridaceae (or Woodsiaceae, depending on classification). Despite its common name, the species is not specifically associated with oak trees; rather, it typically grows in cool, moist, shaded environments including boreal and mixed forests, rocky woodland slopes, stream banks, and shaded cliff faces. <em>Gymnocarpium dryopteris</em> spreads by rhizomes and forms low, spreading colonies with characteristic triangular, three-pinnate fronds that emerge from a slender creeping rootstock. Its geographic range spans Europe and North America, with populations in cool temperate and boreal zones. The species is currently assessed as Critically Endangered in certain regional assessments, suggesting that particular populations face severe decline, likely due to habitat loss, forest fragmentation, and altered hydrology, even if the species retains a broader global range. Biological traits such as lifespan, body size, and diet remain poorly documented at a standardized population level. <em>Gymnocarpium dryopteris</em> is a characteristic indicator of undisturbed cool woodland habitats and is valued for both its ecological role in forest understoreys and its aesthetic appeal.

Shared Countries

Both species can be found in 6 countries:

🇧🇪 Belgium 🇨🇦 Canada 🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden 🇺🇸 United States