Life in the Understory

Insects are the most successful rainforest animals. In the rainforest canopy and understory insects are found in all areas. insects abound: In a study of the rainforest canopy in Peru with 500 cubic meters of plantlife, about the size of a two-car garage, scientists found more than 50 species of ants, 1,000 beetle species, 1,700 arthropod species, and more than 100,000 individuals. A rainforest tree alone can have some 1,200 species of beetle, while a single area of rich forest canopy is projected to have 12,448 beetle species.

Even leeches are found in the understory. Mosquitoes are very plentiful in the rainforest, though on the ground there are generally few puddles for breeding. Because there is no obvious seasonal changes in the rainforests, mosquitoes continue to breed year-long, but slowly. In areas where there are definite seasonal changes mosquitoes breed quickly, and in large numbers during seasonal changes. In the understory, mosquitoes lay their eggs in the leaves turned upside down. Therefore, you may be more likely to get mosquito bites in the understory and the canopy than on the forest floor.

Many insects like stick insects, katydids, leaf hoppers, and mantids have developed incredible behavior, body structure, and color to mimic their surroundings. These insects, which mimic dead and living leaves, half-eaten leaves, sticks, bark, bird droppings, and flower parts, hide from their predators while they hunt and rest.

The Katydids are also known as 'long-horned grasshoppers', but are closely related to crickets. They are common in tropical rainforests but they can be hard to see, this is because they are green and shaped like the leaves and the stems that they live on. Only their loud and distinctive calls give away their presence.

Many of the more commonly seen species are those that live in the grassy edges of the rainforest, such as the 'Snout-nosed Katydids. They are so named because of the long snout that sticks forward past the eyes.

Their calls are often the loud buzzing that can be heard during the night.

As their name suggests, these insects often grow to resemble stems, sticks and leaves. Their camouflage doesn't stop there; the females often lay eggs that look like little seeds. Stick insects are usually not seen, unless they are out of their natural environment. 

Huntsman Spiders' are of the family Heteropodidae . They are often large spiders that look flat, with long, laterally pointed legs. Their long legs can measure up to 16 centimeters. Their legs can also bend forward, which allows them to scurry sideways just like a crab would move. How huntsman spiders look and act are an adaptation to living underneath the bark of trees. The fact that they do not use webs, and that they may chase down their prey, gives them their most commonly used name of “Huntsman”. Huntsman spiders may also wait on tree trunks near busy paths for its prey to come. The Huntsman family can potentially be found all around the world, but seem much more common in the tropics of the rainforests. Huntsman spiders are not poisonous or dangerous to humans.

The stag beetle is a rare, large beetle. It has a metallic green and purple body sheen that makes it one of the most attractive beetle species in the Australian rainforest. It lives among rotting logs and tree stumps. It is endangered by people hunting it because of its beauty. Stag beetles are mainly vegetarians. Adults feed on nectar, young leaves, sap and fruit. They are nocturnal and sometimes attracted to lights.

Stag beetles are kept as pets in Japan and can be bought from vending machines.

Cicadas are insects that have piercing and sucking mouth-parts. They do not have scales like other insects. There are more than 200 Australian species of cicadas. Cicadas are sometimes known as locusts in Australia. Adult cicadas have stout bodies with two pairs of wings. The wing spans of the different species range from about 2.5 cm - 15 cm.

When they are not using their wings they fold back along the sides of the body. The longer, front wing covers the short hind wing, but the wings of each side do not overlap. The front wing is usually glassy and see-through, but some types of cicadas have dull and cloudy wings. The wings are strengthened by a number of thin, firm veins.

Adult cicadas have three pairs of legs all about the same length. Cicadas have large compound eyes, one on each side of the head. They also have three very small glistening simple eyes, called ocelli, on the top of the head. The cicada's antennae, or its feelers, are quite small and bristle-like.

The mouth parts of the cicada are enclosed in a long, thin, beak-like cover. Cicadas feed by piercing the surface of plants with their mouth. They then suck up the sap through a tube. Cicadas may cause some trees to grow slower from the amount of sap that they eat, but the effects are not very noticeable.

Cicadas are hunted in large quantities by birds. They are also carried off by wasps as food for their young.

Cicadas are known for the loud noise they make. Some cicadas that “sing” during the day scare away birds. This is because the noise is thought to be painful to the birds' ears and interferes with their normal communication.

Cicadas spend most of their life underground, living on the sap from plant roots. They may live underground for around six to seven years. As they grow, they shed their skin in different phases of their life.