Common Groundhopper vs common sea hare

Tetrix undulata compared with Aplysia punctata

Taxonomic Classification

Rank	Common Groundhopper	common sea hare
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Arthropoda (Arthropods)	Mollusca (Mollusks)
Class	Insecta (Insects)	Gastropoda (Gastropoda)
Order	Orthoptera (Orthoptera)	Aplysiida (Aplysiida)
Family	Tetrigidae	Aplysiidae
Genus	Tetrix	Aplysia
Species	Tetrix undulata	Aplysia punctata

Evolutionary Relationship

Common Groundhopper and common sea hare share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Common Groundhopper

LC — Least Concern

common sea hare

LC — Least Concern

Physical Characteristics

Attribute	Common Groundhopper	common sea hare
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Groundhopper

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

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

common sea hare

Habitat

Typically found in terrestrial and aquatic habitats including forests and freshwater.

Range

Distributed across Denmark, Norway, Portugal, and Sweden.

Common Groundhopper

The common groundhopper, <em>Tetrix undulata</em>, is a small insect belonging to the order Orthoptera, family Tetrigidae. This species has an exceptionally broad ecological tolerance and is typically found across virtually all terrestrial and freshwater habitat types within its range. Its distribution spans Belgium, Denmark, Luxembourg, Norway, and Sweden, reflecting a wide presence across northern and western Europe. Unlike most grasshoppers, groundhoppers typically lack fully developed hind wings in some individuals and are often found on bare ground, mossy substrates, and near water margins. <em>Tetrix undulata</em> is assessed as Least Concern on the IUCN Red List, indicating stable populations across its European range. No dietary information has been provided for this species. Biological traits of this species remain poorly documented in the scientific literature.

common sea hare

<em>Aplysia punctata</em>, the common sea hare, is a large opisthobranch sea slug in the family Aplysiidae, order Aplysiida, found in the northeastern Atlantic Ocean and Mediterranean Sea, with confirmed records from Denmark, Norway, Portugal, and Sweden. This species typically inhabits shallow subtidal and intertidal zones with abundant macroalgae, feeding primarily on red and green algae — a diet that influences the color of the defensive purple ink it secretes when threatened. <em>Aplysia punctata</em> is a simultaneous hermaphrodite, capable of acting as both male and female during mating, and often forms mating chains involving multiple individuals. It can reach considerable size among European opisthobranch species, though body dimensions vary considerably with age and feeding conditions. The species is classified as Least Concern by the IUCN, reflecting stable populations across its coastal range. Biological traits for this species remain poorly documented in the scientific literature, including precise average data on lifespan, body length, weight, and detailed seasonal dietary patterns, though its general herbivorous feeding on macroalgae is well established.

Shared Countries

Both species can be found in 3 countries:

🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden