Acarol., Mar. 2000. Anderson and Trueman indicated that they were unable to find morphological differences to distinguish the genetic types. The adult female Varroa is oval and flat, about 1.1 mm long and 1.5 mm wide, pale to reddish-brown in color, and can be seen easily with the unaided eye.
Male mites are considerably smaller and are pale to lightly tanned.
Adult bees serve as intermediate hosts when little or no brood is available and as a means of transport. These are also places from which they can easily feed on the bees' hemolymph. The adult bee suffers not only the loss of blood but may be subjected to microbial invasion, leading to a reduced life expectancy. The most severe parasitism occurs on the older larvae and pupae, drone brood being preferred to worker brood. The degree of damage depends on the number of mites parasitizing each bee larva.