Treehoppers and Their Weird and Wonderful Shapes: from Helmets to Humps

Treehoppers might be small, but they are fascinating creatures with blizzard appearance that you and I have even seen. With their quirky shapes and unique behaviors, these little insects offer a glimpse into the wonders of the natural world. Let’s delve into the world of treehoppers and discover what makes them so special.

They have unique and diverse looks

Treehoppers are intriguing insects famous for their unusual and striking looks. They are part of the Membracidae family, which is part of the superfamily Membracoidea, along with the cicadas. There are about 3,200 treehopper species spread across more than 400 genera. 

What sets treehoppers apart is their distinctive helmet-like structure known as the pronotum, which extends from the shield behind their heads. This feature can also extend upward and over the body, making the insects look taller than they really are.

While in most insects the pronotum is a mere simple band, in treehoppers it transforms into extraordinary and varied shapes. These pronota often mimic thorns, leaves, other parts of plants, bird droppings, and other insects like wasps or ants. Some even resemble alien spacecraft. These unusual shapes are believed to help camouflage the insects and protect them from predators.

Treehopper species come in a stunning variety of colors, including shades of bronze and green, and often have unique patterns such as stripes or spots. These insects vary in size, typically measuring between 2 millimeters and 2 centimeters. Besides their distinctive pronota, treehoppers possess powerful muscles in their rear legs that enable them to hop around.

Their nymphs look quite different from the adults, sporting a more “razor-backed” shape with a less prominent helmet-like structure.

They are found everywhere

Treehoppers are widespread, living on every continent except Antarctica, with a preference for tropical climates. They mainly inhabit trees, grasses, and shrubs, choosing locations based on the availability of their favorite food plants. This varies depending on the species and the region. In the northeastern U.S., for example, treehoppers typically gather at oak trees (Quercus spp.) with more than 100 species found there.

Treehoppers are generally not harmful to humans; they do not sting or bite people. Their feeding habits also pose no threat to agriculture or human health.

Treehopper diet

Like planthoppers, treehoppers also pierce the stems or bark of various plants to sip their sweet sap. These insects can feed on over 100 different types of plants, including trees, shrubs, and bushes. While some treehopper species are generalists, feeding on many kinds of plants, others are specialists, sticking to a specific group or type of host plant.

Some of their host plants are fruit trees, ash, elm, and hawthorn, as well as birch, locust, oak, poplar, and chestnut. They also feed on many types of flowering plants like yarrow, sunflower, and aster among others.

To eat sap, they use specialized mouthparts composed of two sharp tubes. One tube injects saliva to keep the plant from sealing off the sap flow, while the other tube draws the sap out. This way, they can feed on a plant’s sap for up to a month.

Their young, called nymphs, usually feed on the sap from softer, non-woody plants such as grasses.

Defend mechanism

Treehoppers have various predators such as birds and lizards, as well as invertebrates such as assassin bugs, ants, spiders, and wasps. To protect themselves, they have quite a few strategies:

• Partnership with ants and bees: When feeding on plant sap, these bugs produce a sweet liquid called honeydew, which is a favorite food for ants and bees. In exchange, these insects protect them from predators and parasites. To communicate with ants, treehoppers send vibrations through the plants they live on.
• Camouflage: With the unique pronotum, these hoppers can blend in seamlessly with their surroundings.
• Chemical camouflage: Some treehoppers can absorb chemical compounds from their host plants, making them less appealing to predators such as ants.
• Vibrational defense signals: In response to predator attacks, oak treehopper mothers and their young produce vibrational signals. The mother’s signals prevent the offspring from signaling, reducing the likelihood of attracting more predators.
• Synchronized group signaling: Treehopper nymphs can coordinate their vibrational signals to send a unified “SOS.” This synchronized signal prompts defensive actions from their mother.

Life cycle

Treehoppers use vibrations to communicate. During mating season, males play vibration-based “love songs” on plant stems to attract females. Treehoppers from different trees have distinct calls, helping them find mates of the same species. If a female is interested, she replies with her own unique vibrations. Interestingly, males might sound like a different species when the temperatures increase. However, according to a study, females can still recognize and respond to these varied calls.

Treehopper species that live on different types of trees usually don’t interbreed, even when they’re nearby. This happens because the females tend to stay on the same tree where they were born, raising their young on that specific type of tree as well.

After mating, females lay their eggs (one at a time or in groups) either by embedding them into the tree’s living tissue or placing them on the surface. In some species, the females protect the eggs by covering them with a frothy secretion that eventually hardens. They can even protect their eggs and stay with the groups of nymphs. These groups are often cared for by ants that are attracted to the honeydew the treehoppers produce.

Once the eggs hatch, the nymphs go through 5 stages of growth, shedding their exoskeletons each time as they develop wings. The final stage ends when the nymph transforms into an adult. These adults continue to eat and find mates, having one or more generations each year. The lifespan of treehoppers typically from egg to nymph to adult takes around 70 days