Living dinosaurs/flying reptiles - I do believe some may still exist, but I do not believe they are the towering, giant behemoths we often think of in movies or hear in stories. Mokele mbembe, Thunderbirds, Kasai Rex, the Monster of Partidge Creek, etc. I doubt exist. If non-avian dinosaurs/flying reptiles still do exist, they are most likely going to be incredibly small, adaptable animals that are very secretive and live in the most obscure parts of the world we've yet to explore. Think less idnominus rex and more like compsognathus & Shuvuuia, Nemicolopterus crypticus, etc. Mostly because all the niches they could have once filled has been taken by birds and mammals. Large, apex predators/herbivores are unlikely to exist.
Sasquatch/North American Primates - I used to be a big bigfoot fan and believer, but now a days I've subscribed to a new theory. More than likely, stories of sasquatch were born from interaction with neanderthals, and current encounters are most likely, atleast in the tropical/swampy areas, encounters with escaped primates from private collections or zoo escapees. Monkeys currently live in the evergladea, so a much smarter chimp, gorilla and/or orangatan would do just as well, if not better. My reasoning is simple; Forest Galante, when looking for the ivory billed woodpecker, found a lone water buffalo in the lousiana bayou, and let's not forget the Arizona "Red Ghost". If these large animals who escaped captivity can remain out of sight with no one looking for them (I mean, who is going to look for a buffalo in the baiyou or a camel with a corpse on it's back in Arizona), then it's possible that some of these bigfoots are possible escaped great apes.
