How to see a spider mite? - briefly
Inspect plant leaves with a 10‑30× magnifying lens, focusing on the undersides where tiny, pale‑green or red specks move slowly; these are the spider mites. Use a bright light and gently shake the foliage to dislodge the insects for easier visual confirmation.
How to see a spider mite? - in detail
Spider mites are minute arachnids, typically 0.2–0.5 mm in length, requiring magnification for reliable detection. Begin with appropriate lighting; natural daylight or a cool white LED source provides the best contrast without heating the plant. Hold the leaf under the light and examine both surfaces, focusing on the undersides where mites commonly congregate.
Use a hand lens of at least 10× magnification. Position the lens close to the leaf, maintaining a short working distance to keep the field of view clear. With the lens, look for the following characteristics:
- Oval or elongated bodies, often pale green, yellow, or reddish.
- Two pairs of legs visible on the dorsal side; the anterior pair may be hidden.
- Fine webbing connecting individuals or attaching to leaf veins.
- Movement patterns: slow, deliberate crawling rather than rapid jumps.
If a hand lens is unavailable, a stereo microscope with 20–40× magnification offers superior resolution. Adjust the focus until the mite’s setae (tiny hairs) become discernible. Capture images with a camera attachment for documentation and further analysis.
For precise identification, collect a sample by gently brushing mites onto a piece of white paper. Transfer the paper to a slide, add a drop of lactophenol or a drop of ethanol to immobilize the specimens, and examine under a compound microscope at 100× magnification. Observe the following diagnostic features:
- Body segmentation: distinct idiosoma and gnathosoma.
- Chelicerae shape: short, hooked structures.
- Setae arrangement: longitudinal rows along the dorsal surface.
- Presence of a ventral anal opening.
The combination of proper illumination, suitable magnification, and systematic observation of morphological traits enables accurate detection of spider mites on plant foliage.