Originally Posted by
joypulv
:( ...they might be just young fleas. You can see the flea shape and legs under a magnifying glass. The legs all tilt towards the end of the flea.
Insects grow in stages. Each stage is called an instar. Young insects feed, get a little fatter, and molt whereupon the old skin, (=exuvia), is cast off, and the new skin (=exoskeleton) emerges from underneath the old skin. The number of instars an insect grows through depends on the species of insect.
Insects have different types of growth strategies where, depending on species, an insect only gets bigger and does not change its basic shape nor grow wings (=no metamorphosis); OR the insect nymph changes slightly and the final instar, which is the adult reproductive stage, grows wings (=gradual metamorphosis); OR the insect larva changes dramatically from an often, but not always worm shape, to a quiescent pupal stage, then emerges as an often winged adult reproductive stage (=complete or full metamorphosis)
Ants, wasps, beetles, butterflies, moths AND fleas undergo complete metamorphosis.
A "young flea" looks nothing like the adult flea most people are familiar with. A larval flea does not have legs and barely has a recognizable head. They have the classic worm insect look. Larval fleas don't even bite. They feed on the dead sloughed skin and dried blood of the host.
A flea with legs is an adult flea, essentially an "old flea". The adult flea is the final instar. It will not grow anymore.
Click on the following links for images:
Flea larvae
Flea adults