Dactyl Eggs are slightly yellow Eggs dropped by Pterodactyls and are worth 10 normal Eggs.

Just like normal eggs, they are very fragile. When they fall down they break. Because of this, they are considerably harder to obtain, as they always fall out of the air. Dactyl eggs are not considered seperate from normal eggs in your total egg count.

When a dactyl is about to lay an egg, its eyes widen to a comedic effect. It will quickly return to normal and said egg will be falling. Burning dactyls will not lay eggs.

In Eggs of Doom speedrun, eggs hurt the player and fall more often.
Dactyl egg

The dactyl egg in the How to play screen.