Prelude

Arthropods are by far the most successful phylum of animals, both in diversity of distribution and in number of species and individuals. They have adapted successfully to life in water, on land and in the air. About 80% of all known animal species belong to the

Arthropoda - about 800,000 species have been described, and recent estimates put the total number of species in the phylum at about 6 million.

Arthropods are found in a great variety of habitats than any other animal group; on top of mountains, at great depths in the ocean and in the icy wilderness of  Antarctica.

They can survive great extremes of temperature, toxicity, acidity and salinity.