Common Duckweed vs common sea hare

Lemna minor compared with Aplysia punctata

Taxonomic Classification

Rank	Common Duckweed	common sea hare
Kingdom	Plantae (Plants)	Animalia (Animals)
Phylum	Magnoliophyta (Flowering Plants)	Mollusca (Mollusks)
Class	Liliopsida (Monocots)	Gastropoda (Gastropoda)
Order	Alismatales (Alismatales)	Aplysiida (Aplysiida)
Family	Araceae	Aplysiidae
Genus	Lemna	Aplysia
Species	Lemna minor	Aplysia punctata

Conservation Status

Common Duckweed

LC — Least Concern

common sea hare

LC — Least Concern

Physical Characteristics

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

Habitat & Geographic Range

Common Duckweed

Habitat

Typically found in grasslands, wetlands, forests, and cultivated landscapes.

Range

Widely distributed across Europe (8 countries), North America (Canada, United States), Oceania and the Pacific (Australia), and South America (Brazil, Guyana).

common sea hare

Habitat

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

Range

Distributed across Denmark, Norway, Portugal, and Sweden.

Common Duckweed

<em>Lemna minor</em>, commonly known as common duckweed, is a tiny floating aquatic plant in the family Araceae, recognized as one of the smallest flowering plants on Earth. Classified as Least Concern by the IUCN, the species enjoys a broad distribution across Europe, North America, Oceania, and South America, colonizing a diverse array of habitats including grasslands, wetlands, forests, and cultivated land with access to standing or slow-moving water. It typically inhabits ponds, lakes, ditches, and quiet streams, forming extensive green mats on the water surface. <em>Lemna minor</em> reproduces predominantly through asexual budding, allowing populations to expand rapidly under favorable conditions. The species provides vital ecosystem services, stabilizing nutrient cycles, reducing algal blooms through competition, and offering food and shelter for aquatic invertebrates, fish, and waterfowl. Due to its sensitivity to water quality, it is frequently used as a bioindicator in ecotoxicological research. Common duckweed has also attracted scientific interest for its potential in wastewater treatment and as a high-protein animal feed supplement. 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 4 countries:

🇩🇰 Denmark 🇳🇴 Norway 🇵🇹 Portugal 🇸🇪 Sweden