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Photo Credit: Roger Klocek 

I’m sexy and I know it!

I am all 'mussel', but never workout. Some say I just look like a pebble, but don't underestimate my patterned shell, short teeth and beak. I stay cool at the bottom of streams and filter tiny bacteria out of the water.

I'd love to stick around, as long as water pollution doesn’t interrupt my groove. 

The ellipse (Venustaconcha ellipsiformis) is a mussel. Its mobility comes from its foot, a muscle that can change its shape and extends between its shells. It can be found in small to medium sized streams, nestling in gravel or sand. Females release fertilized eggs which attach to the fins or gills of fish. Juvenile mussels fall off the fish and live in the streambeds, where they eat by filtering bacteria, protozoans, algae and plankton.

The ellipse needs clean streams for survival. According to the Illinois Wildlife Action Plan, the ellipse is in the greatest need of conservation; it is of special concern on the Indiana Wildlife Action Plan; and the ellipse is labeled as threatened in Wisconsin. The biggest factors in population decline are dams, poor water quality and siltation. 



  • The lifespan of the ellipse is several decades with some living up to a century!
  • To reproduce, males release their sperm into the water and females siphon it into their bodies. 

  • The mottled sculpin (another priority species!), sunfish, sauger and drum are some fish hosts for ellipse eggs.



Prevent pollution of nearby lakes, rivers and groundwater by remaining conscious of water usage.

Always conserve water by turning off the tap, but also be selective of what you flush down the toilet or empty in the drain. Trade traditional cleaning products for environmentally-friendly products such as vinegar and water, and don't litter into bodies of water. Finally, buy organic. This will reduce the presence of pesticides that runoff into bodies of water.



Chicago Wilderness works with our lead partner, Openlands, to drive ellipse conservation efforts. The lead partner, in turn, coordinates with numerous other organizations across the region. The ellipse conservation effort is part of the Chicago Wilderness Priority Species Focus Area.


Sources: Illinois Natural History SurveyMinnesota Department of Natural Resources