Pistia stratiotes (Water Lettuce) Flowers
Odds are if you have a pond you’ve had water lettuce. It’s almost certainly flowered for you too, but unless you’re looking you can miss it completely.
You can also see that it’s a member of the Araceae family with the familiar spathe/spadix flower structure.
All Andrew's Plants 
Strange looking.
Well, isn't this a lovely plant??? The color is beautiful. The center is just great!