Is a crab a atachnid

No, a crab is not an arachnid; it is a crustacean. Crabs belong to the class Malacostraca within the phylum Arthropoda, while arachnids, such as Spiders and scorpions, belong to a different class called Arachnida. Both groups are part of the larger arthropod phylum, but they are distinct in terms of their characteristics and classifications. Crabs typically have ten limbs and gills for breathing, whereas arachnids have eight legs and do not possess gills.