Common Nut Truffle vs Common Seal

Hymenogaster vulgaris compared with Phoca vitulina

Key Differences

• Common Nut Truffle is Data Deficient while Common Seal is Near Threatened.

Taxonomic Classification

Rank	Common Nut Truffle	Common Seal
Kingdom	Fungi (Fungi)	Animalia (Animals)
Phylum	Basidiomycota (Club Fungi)	Chordata (Chordates)
Class	Agaricomycetes (Mushrooms)	Mammalia (Mammals)
Order	Agaricales (Gilled Mushrooms)	Pinnipedia (Seals & Sea Lions)
Family	Hymenogastraceae	Phocidae (True Seals)
Genus	Hymenogaster	Phoca (Harbor Seals)
Species	Hymenogaster vulgaris	Phoca vitulina

Conservation Status

Common Nut Truffle

DD — Data Deficient

Common Seal

NT — Near Threatened

Population: ~500.0K

Trend: Stable →

Physical Characteristics

Attribute	Common Nut Truffle	Common Seal
Diet	—	Carnivore
Average Lifespan	—	30 years
Average Length	—	1.7 m
Average Weight	—	80.0 kg

Habitat & Geographic Range

Common Nut Truffle

Habitat

Typically found in forest floors, decomposing wood, and soil ecosystems.

Range

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

Common Seal

Habitat

Typically found in diverse ecosystems where prey species are available.

Range

Found across Europe (7 countries) and North America (United States). Listed as Near Threatened, this species requires ongoing monitoring to prevent population decline.

Common Nut Truffle

<em>Hymenogaster vulgaris</em>, the common nut truffle, is a hypogeous (below-ground) fungus in the family Hymenogastraceae, order Agaricales. This sequestrate species produces enclosed, truffle-like fruiting bodies that mature underground and rely primarily on small mammals and invertebrates for spore dispersal, as the sporocarps never open to release spores aerially. <em>Hymenogaster vulgaris</em> typically forms ectomycorrhizal associations with hardwood tree species, particularly oaks and beeches, in temperate European forests. Its geographic range includes Denmark, Norway, Portugal, Sweden, and the United States, reflecting a somewhat scattered distribution across temperate zones. The species is currently assessed as Data Deficient by the IUCN, indicating that insufficient information exists to evaluate its conservation status, likely because hypogeous fungi are difficult to survey and their population trends are poorly known. Biological traits such as lifespan, body size, and diet remain poorly documented for this species. As an ectomycorrhizal fungus, <em>Hymenogaster vulgaris</em> plays a critical role in facilitating nutrient uptake in host trees and supporting forest health across its temperate range.

Common Seal

The most widely distributed pinniped, harbor seals inhabit temperate and subarctic coastal waters of both the North Atlantic and North Pacific. Adults reach up to 130 kg and spend roughly equal time at sea hunting fish, squid, and crustaceans and hauling out on beaches or rocks to rest. Their large, expressive eyes are adapted for underwater vision in low light. Harbor seals are a critical food source for orcas, sharks, and polar bears.

Shared Countries

Both species can be found in 5 countries:

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