Common Onion vs common sea hare

Allium cepa compared with Aplysia punctata

Key Differences

• Common Onion is Not Evaluated while common sea hare is Least Concern.

Taxonomic Classification

Rank	Common Onion	common sea hare
Kingdom	Plantae (植物)	Animalia (動物)
Phylum	Magnoliophyta (被子植物門)	Mollusca (軟体動物)
Class	Liliopsida (単子葉植物綱)	Gastropoda (腹足綱)
Order	Asparagales (クサスギカズラ目)	Aplysiida (Aplysiida)
Family	Amaryllidaceae	Aplysiidae
Genus	Allium	Aplysia
Species	Allium cepa	Aplysia punctata

Conservation Status

Common Onion

NE — Not Evaluated

common sea hare

LC — Least Concern

Physical Characteristics

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

Habitat & Geographic Range

Common Onion

Habitat

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

Range

Widely distributed across Africa (8 countries), Asia (4 countries), Europe (23 countries), North America (United States), Oceania and the Pacific (Australia), and South America (5 countries).

common sea hare

Habitat

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

Range

Distributed across Denmark, Norway, Portugal, and Sweden.

Common Onion

<em>Allium cepa</em> is a biennial or perennial bulbous herb in the family Amaryllidaceae, cultivated globally as one of the most widely used culinary vegetables. Its exact wild origin remains debated, though it is thought to originate from Central Asia. Today, the species is grown across Africa, Asia, Europe, North America, South America, and Oceania, adapting to diverse agricultural climates and soil types. Common onion typically grows in grasslands, agricultural fields, wetlands, and cultivated habitats. The plant forms underground bulbs that store nutrients and are harvested for food. It produces distinctive hollow, cylindrical leaves and globular flower heads. Onion is valued for its sulfur-containing compounds, which contribute to its characteristic pungent aroma and flavor, as well as its antimicrobial and antioxidant properties. Its conservation status has not been formally evaluated by the IUCN due to its extensive cultivation and absence of wild population concern. Biological traits including average lifespan, length, weight, and dietary ecology remain poorly documented in standardized wildlife databases appropriate for a cultivated crop species. <em>Allium cepa</em> is among the most economically significant vegetables worldwide, grown in over 175 countries.

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