Illaenurus quadratus
- kingdom: Animalia
- phylum: Arthropoda
- class: Trilobita
- order: Corynexochida
- family: Illaenuridae
- genus: Illaenurus
- species: Illaenurus quadratus
Stillwater
Minnesota- Osceola
Wisconsin
United States
Illaenurus quadratus Stillwater Osceola