Arachnids have 8 legs and do not have wings. They have 2 body parts: the front part (cephalothorax or "head/thorax") has the mouth, eyes, and legs, and the back part (abdomen) is the rest of the body.


Spiders Araneae

spider
The two body parts are distinct and narrow where they join; body does not have segments
Scorpions Scorpiones

scorpion
The two body parts are distinct, but thick where they join; pincers in front, stinger behind.
Harvestmen Opiliones

Harvestman
The two body parts are joined thickly, giving the appearance of a single segmented body.
Pseudoscorpions Pseudoscorpiones

pseudoscorpion
The two body parts are distinct, but thick where they join; pincers in front, no stinger.
Mites and ticks Acari

acari
The two body parts are joined thickly, giving the appearance of a single body; body does not have segments.
Wind Scorpions Solifugae

solifugae
Large mouthparts (chelicerae) in front; long pedipalps (similar to insects' antennae) resemble an additional pair of legs.

Arachnid Orders: Acari; Araneae; Amblypygi; Opiliones; Palpigradi; Pseudoscorpiones; Ricinculei; Scorpiones; Solifugae; Thelyphonida

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Last updated: Mar 7, 2007