Classification of Subclass Acari

Abstract

Mites are the most diverse and abundant of all arachnids, but because of their very small size (usually less than a millimetre in length), we rarely see them with the unaided eye. Mites are ubiquitous and have successfully colonized nearly every known terrestrial, marine and freshwater habitat including polar and alpine extremes, tropical lowlands and desert barrens and surface and mineral soils. More than 55,000 species of mites have been described – a small fraction (about 5 %) of the total number of animal species alive today. Subclass Acari is divided into two superorders – Parasitiformes and Acariformes. More than 15,000 species are reported under Parasitiformes, while more than 40,000 species have been described under Acariformes. Superorders have been further classified into orders and suborders mentioning salient diagnostic characters under each category. Comparative status of orders, suborders and cohorts as described in different systems of classifications has been clearly given in this chapter. More than 896 species of ticks have been authentically described in family Ixodidae and family Argasidae under order Ixodida. Acariformes are more diverse of the two superorders and have been reported under 351 different families.