Varroidae

Varroidae mites inhabit honey bee colonies, specifically within the nest structure of Apis species. They occupy two distinct microhabitats: the exterior of adult bees (phoretic phase) and the interior of brood cells (reproductive phase). In the phoretic phase, adult female mites attach to the thorax or abdomen of adult worker and drone bees. During reproduction, female mites enter uncapped brood cells containing developing larvae, remaining hidden until the cell is capped. They then feed and reproduce within the sealed cell alongside the developing pupa. The mites show preference for specific cell types; Varroa jacobsoni has been observed to preferentially invade shallower worker brood cells when available.

Varroidae has a cosmopolitan distribution in regions where host honey bees are present. The family originated in Asia, where Varroa mites were first documented in 1904. Varroa destructor spread to Europe in the 1970s and reached North America by 1987. Distribution records from GBIF include Denmark, Norway, and Sweden. The mites now occur wherever Apis mellifera is managed commercially, including temperate and tropical regions globally. Seasonal population dynamics vary with climate; in temperate Argentina, reproductive rates differ between spring and autumn.

Varroidae exhibits pronounced seasonal population dynamics tied to host brood availability and climate. In temperate regions, mite reproduction peaks in spring when brood rearing increases, with higher proportions of non-reproductive females observed in autumn. Mite populations within colonies increase during fall, coinciding with reduced brood rearing and the formation of winter clusters. Extended warm fall temperatures, associated with climate change, allow continued foraging activity and mite migration into colonies later in the season than historically observed.

Adult female Varroidae mites feed on honey bee fat bodies, not hemolymph as previously assumed. The fat body tissue, analogous to the mammalian liver, provides nutrients and is involved in detoxification, immune function, and nutrient storage in bees. Feeding occurs during both the phoretic phase on adult bees and intensively during the reproductive phase within brood cells, where the female pierces the prepupa to access fat body tissue.

• Apis mellifera - primary hostEuropean honey bee; highly susceptible host enabling reproduction in both drone and worker brood. Infestations cause severe colony losses worldwide.
• Apis cerana - native hostAsian honey bee; original host of Varroa mites in their native range. Co-evolved resistance mechanisms including efficient mite removal and reproduction restricted to drone brood only.

Varroidae has a heteromorphic life cycle with two distinct stages. The traveling (phoretic) stage involves adult female mites dispersing on adult bees. The reproductive stage occurs within sealed brood cells: a fertilized female enters an uncapped cell before capping, hides in brood food, and begins feeding when the larva reaches the prepupal stage. She lays an unfertilized male egg first, followed by fertilized female eggs at approximately 30-hour intervals. Mites undergo two developmental stages before maturity. The male mates with mature sisters within the cell. When the adult bee emerges, the mother mite and mated daughter mites exit on the new bee.

Female Varroidae mites exhibit specific cell-seeking behavior, preferentially invading brood cells shortly before capping. They demonstrate photophobic behavior, hiding in brood food until the cell is sealed. The mites are not highly mobile independently and rely on host bee behaviors for dispersal between colonies. They exploit bee behaviors including drifting of workers between hives, robbing of weakened colonies, and reduced swarming in managed settings to spread. Mites can be dislodged by grooming behaviors in resistant host lines.

Varroidae functions as an obligate ectoparasite of honey bees, with significant impacts on host population dynamics. The mites transmit pathogens, most notably deformed wing virus, and their feeding on fat bodies compromises host immune function and nutrient storage. In natural settings with widely spaced colonies and periodic swarming, mite-host relationships may reach equilibrium. In managed apiculture with high colony densities and suppressed swarming, mite populations can grow unchecked, contributing to colony collapse. The family represents a case study in the ecological consequences of host-parasite co-evolution disrupted by host switching and anthropogenic environmental modification.

Varroidae, specifically Varroa destructor, is the single greatest threat to managed honey bee colonies globally, causing substantial economic losses in apiculture and agricultural pollination services. The mites contribute to colony losses exceeding 20-45% annually in the United States. They necessitate intensive management including chemical treatments (synthetic acaricides and organic acids), cultural practices (drone brood removal, comb culling), and mechanical controls (screened bottom boards). Acaricide resistance has developed in Varroa populations. Research explores alternative controls including elevated carbon dioxide during winter storage, mite-resistant bee breeding, and microbial biopesticides. The family exemplifies how parasitic arthropods can become catastrophic pests following host range expansion.

• TropilaelapsAnother family of parasitic mites affecting honey bees, distinguished by smaller size, faster reproduction, and inability to feed on adult bees—reproduction occurs only in brood cells. Tropilaelaps remains primarily in Asia and has not achieved the global distribution of Varroidae.
• Acarapis woodi (tracheal mites)Internal parasitic mites of honey bees that inhabit the tracheal system rather than being external ectoparasites. Different life cycle, habitat, and pathological effects distinguish them from Varroidae.

• mites
• parasites
• honey bees
• Apis
• agricultural pest
• ectoparasite
• pollinator health
• acarology
• integrated pest management
• colony collapse disorder

• BugGuide
• GBIF taxonomy match
• NCBI Taxonomy
• Catalogue of Life
• How the Varroa Mite Co-Opts Honey Bee Behaviors to Its Own Advantage
• Survey Shines Light on Beekeepers' Efforts to Manage Varroa Mites
• Mite-Resistant Russian Honey Bees Might Not Prevent Varroa Infestations
• Neonicotinoid Exposure Worsens Varroa Mite Infestations in Honey Bees, Study Shows
• Could Carbon Dioxide Be a New Tool Against Varroa Mites?
• Varroa Mites: New Guide Outlines Integrated Pest Management Options
• Reproduction in the Honeybee Brood mite, Varroa jacobsoni (Acarina: Varroidae)
• Reproduction of Varroa jacobsoni (Acari : Mesostigmata: Varroidae) in temperate climates of Argentina
• Distribution of Varroa jacobsoni Female Mites in Honey Bee Worker Brood Cells of Normal and Manipulated Depth (Acarina: Varroidae)
• Assessing the antiparasitic potential of Bifidobacterium sp. Ersapi20 isolated from the cuticle of honeybees against Varroa destructor Oudemans, 1904 (Acari: Varroidae)