What are two-spotted spider mites?
Two-spotted spider mite (Tetranychus urticae) is a pest of many crops throughout the world. Despite their small size, they are capable of very rapidly doing severe damage, due to their great reproductive capacity. There are more than 1200 species worldwide and many of them are major crop pests. The two-spotted spider mite (Tetranychus urticae) is by far the most important species in greenhouses and many outdoor crops.
Life cycle of two-spotted spider mite
Two-spotted spider mites are small and have eight legs. Adult females are about 0.5 mm long. They have an oval body that is rounded at the rear end. Their colour can vary from orange, light yellow or light green, to dark green, red, brown, or almost black.
Males are smaller and more active than the females, with a body that is narrower and more pointed at the rear. Colour is very variable: from light yellow or orange to dark yellow or brown.The colour of the adults often depends on the crop in which they occur (e.g. on cucumbers they are often yellow-brown, on tomatoes they are mainly red-brown).
Both males and females usually have two large black spots, giving rise to the common name, “two-spotted spider mite”. The spots can vary in both form and size. The red eyes can be seen in all stages.
Recognize two-spotted spider mite
Spider mites can be identified by the following characteristics:
- Size and shape: Spider mites are tiny, adults are about 0.5 mm long in length. They have an oval-shaped body with eight legs, which distinguishes them from insects that have six legs.
- Color: Spider mites can have a variety of colors, including green, yellow, red, brown, or black. Two-spotted spider mites have two large dark spots on their body.
- Movement: Spider mites are slow-moving and tend to cluster on the undersides of leaves, where they feed on plant sap. They produce fine webbing over the infested area.
- Damage: Spider mites can cause damage to leaves by piercing the plant cells and sucking out the contents. This can result in yellowing, speckling, or browning of the leaves. Severe infestations can cause the leaves to dry up and fall off the plant.