Environment | ANIMAL TRACKER

Oriental long-headed locust

by Rowan Hooper

* Japanese name: Shouryou-batta
* Scientific name: Acrida cinerea antennata
* Description: Although it is called the long-headed locust, this member of the grasshopper family of insects has a stranger appearance than the more familiar swarming locust. “Shouryou” refers (bafflingly) to the Buddhist word for the spirit of the dead, while “batta” means grasshopper. It has hugely long hind legs, and the body is 4-5 cm long in males, 7-8 cm long in females. The head is very long, sharp and triangular, tipped with two long antennae. This grasshopper comes in two color types, green and brown, but the head shape never leaves any doubt in identifying the species.
* Where to find them: In grass, all over Japan, in summer and autumn. Long-headed locusts are often found in vacant lots around houses, but they are even more commonly heard. The insect rubs the inner surface of its hind legs against the outer surface of the forewings, making a “chiki-chiki” sound that accounts for its other name of chiki-chiki batta.
* Food: Vegetation, particularly rice. Locusts are a major crop pest worldwide, and swarms can cause serious damage. Fortunately for rice farmers, the long-headed locust doesn’t swarm. It does, however, eat the leaves of rice plants.
* Special features: Females are bigger than males because they lay a large mass of eggs, surrounded in a foamy, protective substance. Eggs take more energy to produce than sperm, so females are bigger. In both sexes, the stilt-like hind legs are specialized to store energy like a coiled spring. This energy can be almost instantaneously unleashed if the insect is startled, and the sudden kick propels the animal away. Grasshoppers grow by molting, and just before and after the final molt to adulthood, the exoskeleton is soft and weak. This means that kicks cannot be performed with the same power, lest they damage the exoskeleton. Instead, the insect kicks by conventional muscle contraction, rather than releasing stored energy. After about two weeks the body is strong enough not to be damaged by kicking; the locust modifies its kicking behavior until its body is strong enough to cope.