Fleas are insects mentioned briefly in the DreamWorks Dragons franchise.
Fleas are wingless insects from the Order Siphonaptera. They are parasites of mammals and birds, consuming their blood, and as adults, living on their skin under fur and feathers. Because of this, they are vectors of different diseases such as Murine typhus and Bubonic plague.
There are over 2,000 species of flea worldwide. Many are generally are species-specific to their hosts, but will take a blood meal where they can if their preferred host is not available. The adult life stage ingests the blood of their hosts. Eggs are laid on the host and around the environment. the eggs hatch into larvae which will eat anything available to them, including but not limited to plant material, blood, and feces. Larvae then weave cocoons to become pupa and emerge only when a suitable host is present. Because of this, a home or other area may appear free of fleas, only to suddenly have adults emerging enmasse.
Even though they are wingless, their hind legs are very long and powerful, allowing them to jump 50 times their body length. They have claws at the end of each limb to prevent being dislodged.
Fleas do not have a function in the Franchise nor in real life. They are, however, major pests of humans and animals, and are difficult to get rid of. The flea of the Black Rat was a carrier of the plague, and responsible for the Black Death in the 1300's that wiped out at least a third of the human population of Europe.
|“||Stormfly can shoot a flea off a yak's tail from 20 yards. [src]||”|
|— Fishlegs threatening a Dragon Hunter|
|“||Come on, Ruff, remember when we picked the fleas out of Uncle Uggard's back hair? And then you got fleas because of it? [src]||”|