They are called 'tadpoles'.
A young bee is called a larvae.
Larvae.
Spat
The larva of a silkworm moth is called silkworm caterpillar.
The midge larvae breathes through a breathing tube that sits at the bottom of their abdomen. Midge larvae's are often called chironomid.
The larvae of a beetle are known as "grubs". However, some are also referred to as "scarabaeiform".
the larva is called the Planula
Larvae, after they hatch.
Larvae or nymphs
the larva of a dragonfly is called a nymph, It also lives in water, the dragonfly lives over a pond to catch small bugs.
There are many local names for them but the usual one is elver, although they aren't really larvae.