I bet it was a Male mantis, they don't get very big. It's pretty late in the season for baby manti. It is getting close to egg sack laying/formation time so if your lil' fella "gets lucky" it'll be his head...
I bought five mantis egg sacks for my garden this spring, I haven't seen any running around in months. I even captured a female and released her a few weeks ago, same story. I think the birds are eating them.
This year's container garden: Tomatos, squash, cucumbers (complete failure again), and peppers.
I also dug up all the crabgrass and seeded with bentgrass (putting green grass) it is coming in nicely where the dogs are allowing it. Most of the lawn is Bermuda grass which I actually like because the dogs can't seem to kill it, and I can cut it really low (middle setting on a reel mower, maybe 1/2 to 3/4 inch). The bentgrass I overseeded into the Bermuda is slowly coming up.
That bentgrass seed is fairly expensive, I think, 1 lb cost about 16 bucks. 1lb/1000 sqft, lucky I have a tiny backyard. 30 ft by maybe 60-80 ft. Nice thing about the bentgrass seed I got is that it sprouts in about 3-4 days (or has for me in the three sections I have seeded since mid-August). Takes a lot of water though.