Spongonema tomentosum
- kingdom: Chromista
- phylum: Ochrophyta
- class: Phaeophyceae
- order: Ectocarpales
- family: Ectocarpaceae
- genus: Spongonema
- species: Spongonema tomentosum
- United Kingdom
Sitka
Alaska
Carmel-by-the-Sea
Monterey
Pacific Grove
San Pedro
Sausalito
California
Honolulu
Hawaii
Marblehead
Massachusetts
United States
Malahide
Påarp
Berwick-Upon-Tweed