This is a praying mantis egg case, yes, but we can't tell if it's fresh (laid last autumn and due to hatch this year) or old (being more than one year old and already empty). The seam along the front of the egg case tends to look ragged and open (like popped bubbles in foam) when an egg case is old and empty; it will look intact and fairly smooth-surfaced when it's still viable.

We are not aware of any native praying mantis products being sold (if you purchased an egg case to release in the yard); they are all non-native mantids as far as we're aware, unless you got an egg case from another gardener. The egg case pictured is not that of our native mantis; it's one of the non-native species. Our native Carolina Mantis lays egg cases that have a more elongated, narrow shape. You can view examples in our blog article Get to Know Your Local Mantis.

Miri