Isthmohyla calypsa
Some insects, for example crickets, eat this frog's eggs.  Parasite flies also lay their own eggs in with the frog's egg.  When the fly larva hatch, they eat all the frog eggs nearby.  Between 1991 and 1996, one team of scientists watched 615 clutches (groups) of frog eggs.  65% of them did not have even one egg that hatched.  About a third of these were because of flies.  Frog eggs can also die if they dry out.