Freshwater sponge (Ephydatia)
Ephydatia spp. · Aquatic life
Underwater · Photo: Nicola Crockford / CC BY
Also called Ephydatia muelleri, Freshwater sponge, Ephydatia fluviatilis
How to identify Freshwater sponge (Ephydatia)
- Thin to thick cushionlike crusts, usually without long fingers
- Green, tan, gray or brownish
- Gritty, porous surface with visible pores and small chimneys
- Gemmules packed in the base in late summer and fall
Similar species
Spongilla lacustris often forms upright fingers; telling the two apart for certain takes a microscope look at the spicules in the gemmules. Encrusting bryozoans are made of tubes rather than a porous mass.
Profile
| Season | Grows late spring through fall; survives winter as gemmules. |
|---|---|
| Starts | Grows as water warms past about 55 F |
| Light | Tolerates shade |
| Depth | Shallow to moderate depths on hard surfaces |
| How it spreads or reproduces | Gemmules and fragments carried by water, birds and equipment |
| Habitat | Rocks, logs, pipes and dock pilings in lakes, reservoirs, canals and streams; some tolerate flowing water better than Spongilla. |
Why it matters in a lake
Harmless filter feeders. Heavy growth can occasionally foul screens and pipes, but sponges are usually just a sign of reasonably clean water.
Where it is found
- Idaho: Occasional
- Oregon: Occasional
- Wyoming: Occasional
Classification
| Kingdom | Animalia |
|---|---|
| Phylum | Porifera |
| Class | Demospongiae |
| Order | Spongillida |
| Family | Spongillidae |
| Scientific name | Ephydatia spp. |
Freshwater sponge (Spongilla)
Daphnia (water flea)
Midge larvae (bloodworms)
Keratella (spined rotifer)
Mosquito larvaeNeed a hand?
Found it in your lake?
Send us a photo and we will identify it and tell you what it means for your lake.
Idaho / Wyoming (208) 501-4531Oregon (541) 280-0596