Mites are minute living things belonging to the group of spiders (Arachnidan). They live everywhere. A majority of them are blood sucking parasites. One group of mites, the Varrora mites are parasitic on bees. Their life history takes place in association with the life history of the bee.
The varrora mites are so widely prevalent; no single bee emerges from its cell after development, without being attacked by mites.
The female varrora mite enters the cells of the bee colony, immediately after the eggs are laid by the queen bee. The mite rides on the nurse bee. When the nurse bee proceeds to attend to the egg, the mite enters the cell and lies by the side of the egg.
The mite waits until the bee egg hatches into a larva. When the larva grows big enough, the mite begins to pierce the larval body and suck the blood.
The larva of the bee has to manage with the parasitic mite. It continues its development by shedding its skin and becoming a pupa. A silk cocoon is made at this time, and the pupa is protected within. The cocoon acts as a barrier between the pupa and the mite. But the mite manages to pierce the cocoon and attack the pupa.
The mite starts laying eggs. The eggs hatch into young mites which grow into adults.
By the time, the bee metamorphosis is completed ( in about 20 days from the time egg is hatched), the family of mites are ready to leave the cell along with the adult bee. The mites stick on to the bee, as the bee takes off from the honey comb.
The mites that leave the cell along with the bee are the female mites. The male mites remain in the cells and perish.
This is a strange relationship where the life history of the parasite (mite) runs parallel with that of the host (bee).The mite and the bee appear to be inseparable, and it is inevitable that the bee has to bear with the mite throughout its life.