The term prosoma ( Greek πρό pro 'before' and σῶμα soma 'body') refers to the fore part of arachnids . The eyes of the animals, their paired mouthparts (the chelicerae and pedipalps ) and the eight legs sit on it .
In contrast to the insects , whose body is divided into three tagmata - caput (head), thorax (chest) and abdomen (abdomen) - arachnids have a two-part body structure: as the front body they have the prosoma, which corresponds to a head-chest piece, and the Abdomen (opisthosoma).
Occasionally the forelegs of arachnids are also referred to as the cephalothorax , but this is incorrect and only in the higher crustaceans is the fore-body called that, which is fused from the head ( cephalon ) and the chest ( thorax ), which is fused by the carapace extending from the head is covered.
- Cephalothorax. In: Brockhaus Encyclopedia. 19th edition. Volume 4, 1987, ISBN 3-7653-1104-9 , p. 386.
- Cephalothorax. In: Erwin J. Hentschel , Günther H. Wagner : Dictionary of Zoology. 7th edition. 2004, ISBN 3-8274-1479-2 , p. 135.