Spheniscidae
Definition
Spheniscidae is the biological family that contains all living penguin species. The name derives from the Greek word 'spheniskos', meaning 'little wedge', referring to the penguin's body shape. All members of Spheniscidae are flightless, aquatic birds restricted to the Southern Hemisphere (with the Galapagos penguin just crossing the equator). The family is estimated to have diverged from other seabird lineages roughly 60-62 million years ago. Fossil evidence shows that ancient penguins were much larger than living species, with some reaching 1.7 metres tall.
Related Terms
Aptenodytes is a genus within the penguin family Spheniscidae containing the two largest living penguin species: the emperor penguin (A.
Eudyptes is the most species-rich penguin genus, containing the crested penguins: macaroni, royal, eastern rockhopper, western rockhopper, northern rockhopper, Fiordland, Snares, and erect-crested penguins.
Spheniscus is a genus of four penguin species adapted to temperate and tropical waters: the African penguin (S.
Eudyptula is a genus containing the smallest penguin species: the little blue penguin (E.
Frequently Asked Questions
What does spheniscidae mean in penguin biology?
Spheniscidae is the biological family that contains all living penguin species. The name derives from the Greek word 'spheniskos', meaning 'little wedge', referring to the penguin's body shape. All members of Spheniscidae are flightless, aquatic birds restricted to the Southern Hemisphere (with the Galapagos penguin just crossing the equator). The family is estimated to have diverged from other seabird lineages roughly 60-62 million years ago. Fossil evidence shows that ancient penguins were much larger than living species, with some reaching 1.7 metres tall.
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Glossary entries define the language. FAQ answers common questions; guides carry the longer Survival Lab arguments.
More in taxonomyWhere this definition comes from
Reference bodies behind the taxonomy terminology. Links last checked August 5, 2026.
- IUCN Red List - Global conservation assessments and extinction-risk categories.
- BirdLife Data Zone - Species accounts, distribution, and population summaries.
- Australian Museum - Little penguin biology and coastal breeding behavior.