Mystery bug

Unidentified Bug, Long Key Nature Center

I love seeing new and interesting bugs. I spotted this one yesterday at Long Key Natural Area and Nature Center and thought it looked a little like a milkweed bug but rounder and fatter. Someone in a bug group suggested that it may be an anchor stinkbug ... but I'm not entirely sure about that either. If anyone can confirm that identity or otherwise solve this little mystery, please let me know.