| The grasshopper (Latin: Tettigonioidea) is an Orthoptera superfamily, of the suborder Caelifera with a unique modern similar name of the family. Apart from in Antarctica, more than 6800 kinds of grasshoppers are found on all continents.
Anatomy:
The head with the isolated top of the sinciput, which is often compressed from the sides, sometimes is cone-shaped. The pads consist of 4 segments. The pronotum has a flat or convex top and the flat lateral blades lowered downwards. The wing cases of the male are often with a chirring body. The wing cases and wings often lose flying function, but keep the chirping body. The ovipositor of females is long and compressed from the sides.
Reproduction:
Reproduction usually occurs in the second half of summer; the eggs have an extended-oval, cylindrical or flattened form. The egg mass survives through winter.
Development cycle:
The larvae pip in the spring. After the first molt there are the rudiments of wings in the form of the downwards back bottom corners of the prescutum and metanotum. After the third molt the rudiments of the wings settle down on the back, shape the triangular form and there are longitudinal veins on them. After the last molt the wings occur.
As a rule, the larvae and nymphs of grasshoppers differ from the adult stage in size only by the absence of normally developed wings. But there are kinds where the larvae strongly differ from appearance to the adults. The strongest differences are observed at the transformer mimicries, it means that the larva has the signs of a mimicry which are absent at adult stage.
Chirping:
The sound device settles down on the wing sheaths. On the right wing sheath a “stridulating organ” is situated in the form of the roundish thin transparent membrane which is surrounded with a thick stridulating vein. On the left wing sheath the stridulating organ is opaque, matte and dense. The stridulating vein surrounding it is thick and has dents. This vein carries out the bow role, and the "stridulating organ" serves as the resonator when chirring.
During chirping, a grasshopper raises and moves apart the wing sheaths, and that results in them vibrating here and there, and, as a result, the "bow" dents rub on the framework of the "stridulating organ " of the right wing sheath.
Each kind of grasshoppers has a specific set of published sounds. In most cases males have the sound device only, however there are kinds at which females chirp also.
The hearing aid is on the shins of the forward feet and has the oval membranes which are located on both parties of a shin and carrying out function of eardrums. More often membranes are opened; some kinds are supplied by the lids closing membranes almost completely. The internal part of a hearing aid has a difficult structure consisting of the terminations of nerves, sensitive cages, muscles and two branches of tracheas from which all approach the eardrum. Thanks to the pressure of the air in the membrane the tracheas are always tense.
The biotopes of the grasshoppers are extremely various — from the tropical jungle and deserts to the tundra and high-mountainous Alpine meadows. Unlike other longicorn orthopterous insects, the grasshoppers live openly on plants, instead of using holes in soil or a tree.
Mimicry:
Very often the grasshoppers have the appearance and coloring similar to the appearance and coloring of leaves or other parts of plants on which they live. The grasshopper Elimaea poaefolia which lives on the Malay Archipelago has a strongly extended body similar to a stalk of the plant on which it sits.
Masking is reached thanks to a strong expansion of the wing sheaths, and also thanks to their specific nervuration. Depending on the coloring they simulate either healthy or dying off and dead leaves.
On the leaf like wings of the Cycloptera elegans there are brown stains like the damage on leaves by a parasitic mushroom. The Tanusia wing sheaths’ maculation simulates the beginning of the decomposition of the sheet, and rough edges make the impression, that the sheet is damaged or broken off. Acridoxena hewaniana has a strongly damaged look to their wings also.
Some Indo-Malayan grasshoppers living in trees, simulate lichens. So, for example, the Javanese Satrophyllia femorata, sitting motionlessly with the short moustaches extended forward and the forward feet on a tree branch, merges with the general background of the lichens covering this branch.
Diet:
The overwhelming majority of grasshoppers are omnivorous with the propensity to be a predator. Some kinds only ear plants. Some kinds are also noted as agricultural wreckers. Usually, because of the low density of the population, harm from them is insignificant, but some kinds are capable, like locusts, to do much harsher damage.
In the countries of East and South East Asia grasshoppers have found an application as a culinary dish and, because of the cute chirping, a pet ( in China the price for a "thoroughbred" male grasshopper can reach $16). |
