Black Cutworm vs Common Rock Borer

Agrotis ipsilon compared with Hiatella rugosa

Taxonomic Classification

Rank	Black Cutworm	Common Rock Borer
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Arthropoda (Arthropods)	Mollusca (Mollusks)
Class	Insecta (Insects)	Bivalvia (Bivalvia)
Order	Lepidoptera (Butterflies & Moths)	Adapedonta (Adapedonta)
Family	Noctuidae	Hiatellidae
Genus	Agrotis	Hiatella
Species	Agrotis ipsilon	Hiatella rugosa

Evolutionary Relationship

Black Cutworm and Common Rock Borer share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Black Cutworm

LC — Least Concern

Common Rock Borer

LC — Least Concern

Physical Characteristics

Attribute	Black Cutworm	Common Rock Borer
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Black Cutworm

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, and tropical and subtropical grasslands and savannas, among 6 distinct biome types spanning the Afrotropic and Palearctic realms. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Africa (7 countries), Asia (Taiwan), Europe (5 countries), North America (Canada, United States), and South America (Chile).

Common Rock Borer

Habitat

Native to Europe and North America, inhabiting ecosystems characteristic of the region.

Range

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

Black Cutworm

The Black Cutworm (Agrotis ipsilon) is a species in the genus Agrotis. It is currently classified as Least Concern on the IUCN Red List. Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, and tropical and subtropical grasslands and savannas, among 6 distinct biome types spanning the. Widely distributed across Africa (7 countries), Asia (Taiwan), Europe (5 countries), North America (Canada, United Stat...

Common Rock Borer

<em>Hiatella rugosa</em>, the common rock borer, is a bivalve mollusk in the family Hiatellidae, order Adapedonta. It is distributed across the North Atlantic, with documented records from Denmark, Norway, Sweden, and the United States. The species is assessed as Least Concern on the IUCN Red List, suggesting stable populations across its range. Common rock borers typically inhabit rocky intertidal and subtidal zones, boring into soft substrates including sandstone, shale, chalk, and compacted sediment using mechanical abrasion from their shells. This boring behavior provides the species with protection from predation and wave disturbance. <em>Hiatella rugosa</em> is a suspension feeder, typically extracting phytoplankton and suspended organic particles from the water column through its siphons. The genus Hiatella is considered nearly cosmopolitan, with species occurring from polar to tropical seas. Rock borers are small bivalves, typically reaching only a few centimeters in shell length. They are common components of rocky shore communities and serve as prey for predatory snails, shorebirds, and small fish. Biological traits such as precise lifespan, body measurements, and diet composition remain poorly documented in quantitative ecological studies for this taxon specifically.

Shared Countries

Both species can be found in 4 countries:

🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden 🇺🇸 United States