For the identification of insects and other fauna and flora of South Africa: please click on the following links:
Insects and related species: Antlions - Ants - Bees - Beetles - Bugs - Butterflies, Moths and Caterpillars - Centipedes and Millipedes - Cockroaches - Crickets - Dragonflies and Damselflies - Grasshoppers and Katydids - Mantis - Stick Insects - Ticks and Mites - Wasps - Woodlice
Plants, Trees, Flowers: (Note: Unless plants fall into a specific species such as Cacti, they have been classified by their flower colour to make them easier to find) Bonsai - Cacti, Succulents, Aloes, Euplorbia - Ferns and Cycads - Flowers - Fungi, Lichen and Moss - Grass - Trees
Animals, Birds, Reptiles etc.: Animals, Birds, Fish and Crabs - Frogs - Lizards - Scorpions - Snails and Slugs - Snakes - Spiders - Tortoise, Turtles and Terrapins - Whipscorpions
Other photography: Aeroplanes - Cars and Bikes - Travel - Sunrise - Water drops/falls - Sudwala and Sterkfontein Caves etc.

Videos: YouTube

Monday, January 17, 2011

Cicada

I know that the constant whirring sound they make drives some people crazy but try to find them, and they are nowhere to be seen. Because of this difficulty, it is always nice to eventually find one.
Worldwide there are between two thousand and three thousand different species. Most of a cicada’s lifecycle is spend underground where they live as nymphs feeding on the juices from tree roots by inserting their sucking mouthparts into the roots. Here they may spend years and go through several instars (developmental stages) and moults before finally emerging to go through a final moult outside on the trunk of a tree.
The carapace splits open lengthwise along the dorsal (top) side of the nymph to allow the new cicada into the outside world. It takes a while for the carapace and wings to harden before the cicada is ready for its adult life lasting but a few weeks. After mating, the female cuts slits into the bark of a twig and deposits her eggs there. When the eggs hatch after about six weeks, the newborn nymphs drop to the ground, where they burrow and start another cycle. Most cicadas go through a life cycle that lasts from two to five years, although some American species have a life cycle of seventeen years.
The intriguing question is how do these small insects produce that deafening sound and for what purpose? Well, the interesting thing about these noisy bugs is that only the males are calling. The reason? Well, to attract females of course. Each species has its own distinctive call and only attracts females of its own kind even though rather similar species may co-exist. The apparatus used by cicadas for producing the sound is quite complex and differ completely from insects such as crickets and grasshoppers in which sound is produced by means of stridulation, when different body parts are rubbed together.

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