spineless hornwort
- kingdom: Plantae
- phylum: Tracheophyta
- class: Magnoliopsida
- order: Ceratophyllales
- family: Ceratophyllaceae
- genus: Ceratophyllum
- species: Ceratophyllum echinatum
Windsor
Quebec
Canada
East Haven- New Haven
Connecticut- Aberdeen
- Cabin John
Maryland- Dunes City
Oregon- Seattle
Washington
United States