Define Class – Arachnida?

The class Arachnida (Arachnida = spider) has terrestrial and few aquatic animals. It
includes spider, scorpions and mites.

1. Prosoma bears. six pair of appendages: one pair of clielicerae, one pair of pedipalpi and four pairs of walking legs.
2. Abdomen is generally devoid of appendages.
3. Respiratory organs are tracheae, book lungs and book gills.
4. Excretion is performed by malpighian tubules and coxal glands.
5. Sexes are separate but sexual dimorphism is not conspicuous.

So, you have refreshed your background knowledge of1.he characters of subphylum Chelicerata and class Arachnida. Let us now study individuals examples under the class Arachnida.