Clover Cutworm vs Common Rock Borer

Anarta trifolii compared with Hiatella rugosa

Taxonomic Classification

Rank	Clover 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	Anarta	Hiatella
Species	Anarta trifolii	Hiatella rugosa

Evolutionary Relationship

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

Conservation Status

Clover Cutworm

LC — Least Concern

Common Rock Borer

LC — Least Concern

Physical Characteristics

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

Habitat & Geographic Range

Clover Cutworm

Habitat

Inhabits tropical and subtropical dry broadleaf forests and deserts and xeric shrublands within the Afrotropic biogeographic realm.

Range

Widely distributed across Africa (Cabo Verde), Asia (Yemen), Europe (4 countries), and North America (Canada, United States).

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.

Clover Cutworm

The clover cutworm (Anarta trifolii) is a noctuid moth in the family Noctuidae, order Lepidoptera, with a wide distribution spanning Europe, Asia, Africa, and North America. The species has a characteristic cutworm larva that severs plant stems near the soil surface or feeds on leaves and developing seeds, causing significant damage to crops. Primary host plants include clover (Trifolium), alfalfa, beet, and various other broadleaf crops and weeds, making A. trifolii an agricultural pest of moderate to significant importance in affected regions. Adults are brownish-grey moths with subtle wing patterns typical of the noctuidae family, and like most noctuids, they are nocturnal and attracted to light sources. The species is highly mobile, with adults capable of long-distance migration that enables rapid colonization of new agricultural areas. A. trifolii inhabits a broad range of open habitats including agricultural fields, meadows, steppes, and disturbed grasslands across its extensive range. Its polyphagous larval diet and migratory adult behavior contribute to its wide geographic range spanning multiple continents. In Europe, it is found from the Mediterranean to Scandinavia; in North America it occurs in both Canada and the United States. A. trifolii is classified as Least Concern on the IUCN Red List, with populations considered stable and the species benefiting from the widespread availability of agricultural host plants. Natural enemies include parasitoid wasps and tachinid flies, along with pathogens including nuclear polyhedrosis viruses used in biological control.

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