What does a Varroa mite look like on bees? - briefly
The Varroa destructor is a small, reddish‑brown parasite about 1–2 mm long, typically seen attached to the underside of a honey bee’s abdomen or clinging to the thorax. It has a flattened, beetle‑like body with short legs that grip the bee’s cuticle.
What does a Varroa mite look like on bees? - in detail
Varroa destructor is a small, oval arachnid measuring 1.1–1.6 mm in length and 1.0–1.4 mm in width. The body is dorsoventrally flattened, giving a slightly teardrop shape when viewed from the side. The exoskeleton appears pale brown to reddish‑brown, often blending with the bee’s cuticle, which makes visual detection difficult without magnification.
Key visual characteristics:
- Size: comparable to a pinhead; larger than a typical pollen grain.
- Shape: rounded posterior, tapering anteriorly; legs are short, tucked against the body.
- Color: translucent to light brown; may appear darker when engorged with hemolymph.
- Legs: eight legs, each ending in small claws; barely visible without a microscope.
- Abdomen: expands when feeding, giving a swollen appearance that can be observed on the bee’s thorax or abdomen.
Typical attachment sites on adult workers and drones:
- Between the third and fourth abdominal segments (sternal plate); the mite inserts its mouthparts into the hemolymph.
- Near the base of the wings; less common but occasionally observed during grooming.
On developing brood (larvae and pupae), mites are found:
- Within the capped cells, attached to the underside of the pupal abdomen.
- Under the cell cap, where they can be seen as a tiny, moving speck.
Diagnostic signs on the host bee:
- Small, dark specks that may shift position when the bee moves.
- Mottled or pale patches on the cuticle where the mite has fed, often on the thorax.
- Reduced lifespan or deformed wings in heavily infested individuals, indicating chronic parasitism.
For reliable identification, a stereomicroscope at 20–40× magnification is recommended. The mite’s dorsal shield (idiosoma) should be visible, and the legs can be discerned as minute extensions. Engorged females appear markedly larger and more opaque, while male mites are slightly smaller and lighter in color.