The scuds I bought look like the ones in this series of pictures (bottom picture of the 4 in the post by Bill D about 3/4 of the way down the page in this link shows them fairly well)
Scuds in Bill's aquarium The body of your critters seems to be broad all the way to the back, so it may be a cousin to the ones I/Bill D have?
I bet they are closely enough related that if they were found natively in waters in your area that they probably are invertebrates in that same family. The fish probably love to snack on them
A better close up picture would help. And it always pays to be cautious before introducing a new critter in the pond.
Did they come from your pond already? Where was the minnow trap if you are planning to move them to your pond?
