Three lined lema beetle







Lema trivittata

Three lined potato beetle


This beetle is mostly yellow with three very obvious black stripes along its body, and 2 black dots on its pronotum behind the head. My beetle also has whitish stripes next to the black ones. It seems this beetle can also have a brighter orange head, pronotum, body and legs. The eggs are quite distinctive as they have black tips. The grub-like larvae are also different in that they carry their ‘poo’ on their back. There is also a three lined potato beetle which is very closely related but a brighter orange colour, without the white stripes next to the black. Also similar is the cucumber beetle, which doesn’t have the white stripes next to the black stripe nor the two dots behind the head. All are leaf-eating pests.

Adult size: 7 mm

Out and about

Found in the summer months when their feed plants are growing. Native to North America found along east coast of Australia mainly in the temperate and subtropical regions. There is a species found in South Africa (Lema daturaphila) which is causing some confusion. Some references use this name but they may actually be the same species.

Reproduction and Life cycle

Numbers can breed up very quickly over summer as their cycle can produce two generations a season and each female can lay 20-30 eggs at a time. The female lays her eggs on a host plant where the hatched larvae feed before dropping to the ground to pupate in the soil and emerge as adults. The adults over winter in sheltered spots and come out again once the temperature starts to warm up again.

To deter

To control

-spray with pyrethrum -spray with neem oil -a Bt (Bacillus thuringiensis) spray on the larvae

Plants to repel

Plants to attract


Lady beetle / Lacewings / Assassin bugs / Spiders
Why they are a Pest
This beetle generally eats plants of the Solanaceae family which includes potatoes, tomatoes and eggplant. The beetle in my photo is on a cucurbit leaf so perhaps all three of these beetles like the same crops.