cicada

Latin-English. ‘Tree cricket’. Name for insects of the order Hemiptera in the family Cicadidae, of which there are many species (fig.). A total of 152 species with 5 additional varieties and 1 undescribed species from 35 genera have been identified in Thailand alone. They are usually more often heard than seen and are a symbol of the wild. They are especially recognized by their loud distinctive sound produced by only the males (to attract females) and which can be as loud as over a hundred decibels, making them among the loudest of all insects. Their sound is produced by complex membranes on the sides of the abdominal base and which are called tymbals. They produce their high pitched noise by rapidly vibrating these membranes whilst enlarged chambers derived from the tracheae amplifies the sound even more. They can also modulate the noise by wiggling their abdomens toward and away from the surface that they are on. They have short antennae and two semi-large compound eyes that sit wide apart on the head, as well as three smaller eyes in between those, located on top of the head. These so-called ocelli are able to recognize differences in light and are thought to help avoid threats from above, such as attacks from aerial predators. Their typically often transparent wings are well-veined and adults are generally between 2 and 5 centimeter long (fig.), although some tropical species, may reach up to 15 centimeter, like the Empress Cicada (Pomponia imperatoria) from Malaysia. Some are rather dull while others, such as Proretineta vermacula, are more colourful (fig.). Their life cycle (fig.) starts when a female deposits her eggs into the bark of a twig after mating. When the eggs hatch, the newborn nymphs drop to the ground, where they burrow and start their underground lives. Finally they dig an exit tunnel using their strong front legs and surface (fig.). Then they moult by shedding their skins on a nearby plant or tree and emerge as an adult. Cicadae or cicadas are not harmful to humans and they don't bite or sting. However, they drink tree sap, which is their principal food, and after their bodies took the necessary nourishment and water from the sap, waste matter and fluid accumulate in a rectal pouch, and is  disposed off all at once through the anus, spraying the fluid in short burst from the trees they sit on, wetting anyone or anything underneath. These brief showers are commonly referred to as cicada rain. Some people eat cicadae and they are used in traditional Chinese medicine for hearing-related problems. Being one of the longest living insects, the cicada became a Chinese symbol of eternal youth, happiness and longevity. Hence, it is often found depicted either incorporated in Chinese art (fig.) or as an artefact in its own right (fig.). Before burying their deceased, relatives of wealthy Chinese families would in the past insert a jade carving of a cicada inside their mouth, to assure that the deceased became immortal and would have a blissful afterlife. Sometimes called cicala or cicale, and in Thai known as jakkajan. See also froghopper. 回