Stephanodiscus
Stephanodiscus spp. · Phytoplankton
Under the microscope · Photo: Berezovska / CC BY-SA 4.0 (Wikimedia Commons)
Also called Centric diatom
How to identify Stephanodiscus
- Under the microscope: round disc shaped diatoms with radiating rows of dots across the whole face
- A ring of small spines around the edge
- Single cells, golden brown
- In the water: spring blooms can make reservoirs look brownish or murky
Similar species
Cyclotella has a smooth or wavy center that differs from the outer ring; Discostella has a starlike center.
Profile
| Season | Late winter and early spring blooms, sometimes under ice, and again in fall. |
|---|---|
| Starts | About 35 to 50 F |
| Light | Low light tolerant |
| Depth | Mixed water column |
| How it spreads or reproduces | Cell division |
| Habitat | Nutrient rich lakes, reservoirs and large rivers; very common in Snake and Columbia system reservoirs. |
Why it matters in a lake
An early spring diatom of nutrient rich water. Big blooms clog filters and add organic matter that later fuels summer algae growth.
Where it is found
- Idaho: Common
- Oregon: Common
- Wyoming: Common
Classification
| Kingdom | Chromista |
|---|---|
| Phylum | Bacillariophyta |
| Class | Mediophyceae |
| Order | Stephanodiscales |
| Family | Stephanodiscaceae |
| Scientific name | Stephanodiscus spp. |
Fragilaria
Cyclotella
Asterionella
Navicula
Aulacoseira
Ulnaria (Synedra)
Nitzschia
Tabellaria
Melosira
GomphonemaNeed a hand?
Want to know what is in your water?
Lab counts of the algae in your lake show what is growing, how much and whether a bloom is coming.
Idaho / Wyoming (208) 501-4531Oregon (541) 280-0596