Varroa destructor

Varroa destructor, the Varroa mite is an external parasitic mite that attacks and feeds on the honey bees Apis mellifera and Apis cerana. The disease caused by the mites is called varroosis. The Varroa mite can reproduce only in a honey bee colony. It attaches to the body of the bee and weakens the bee by sucking fat bodies. The species is a vector for at least five debilitating bee viruses, including RNA viruses such as the deformed wing virus (DWV). A significant mite infestation leads to the death of a honey bee colony, usually in the late autumn through early spring. The Varroa mite is the parasite with possibly the most pronounced economic impact on the beekeeping industry. Varroa is considered to be one of multiple stress factors contributing to the higher levels of bee losses around the world. File:Varroa destructor protonymph (5048063601).jpg|''V. destructor'' protonymph File:Varroa destructor deutonymph.jpg|Deutonymph of ''V. destructor'' File:Varroa destructor (Adult Male) (5048079279).jpg|''V. destructor'' adult male File:Female Varroa destructor on the head of a bee nymph (5048103407).jpg|Adult female in lateral view The adult female mite is reddish-brown in color, while the male is white. Varroa mites are flat, having a button shape. They are 1–1.8 mm long and 1.5–2 mm wide, and have eight legs. Varroa mites lack eyes. One mite weighs approximately 0.453 mg. Mites reproduce on a 10-day cycle. The female mite enters a honey bee brood cell. As soon as the cell is capped, the Varroa mite lays eggs on the larva. The young mites, typically several females and one male, hatch in about the same time as the young bee develops and leave the cell with the host. When the young bee emerges from the cell after pupation, the Varroa mites also leave and spread to other bees and larvae. The mite preferentially infest drone cells, allowing the mite to reproduce one more time with the extra three days it takes a drone to emerge compared to a worker bee. This can cause genetic defects such as useless wings or viruses and fungi in the bee.