gnathosoma

arachnid anatomy

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Last updated

June 29, 2026

Quick Summary

The term "gnathosoma" refers to the capitulum in arachnids. The capitulum is the anterior part of the cephalothorax, which is one of the two main body regions of most arachnids, the other being the abdomen. Arachnids, a class of arthropods, possess an exoskeleton and jointed appendages. They typically lack jaws and inject digestive fluids into their prey before consuming it. The cephalothorax bears six pairs of appendages, including the chelicerae (mouthparts) and pedipalps, followed by four pairs of walking legs. The gnathobase is a part of an arthropod appendage that aids in carrying or chewing food.1234

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acarid
External features
An anterior region called the gnathosoma contains the mouth, specialized feeding appendages (chelicerae), and segmented structures called palps, or pedipalps. The mouth or buccal cavity joins the pharynx internally, and paired salivary glands may discharge into the mouth or in front of its opening. The chelicerae are basically three-segmented pincerlike…
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An anterior region called the gnathosoma contains the mouth, specialized feeding appendages (chelicerae), and segmented structures called palps, or pedipalps. The mouth or buccal cavity joins the pharynx internally, and paired salivary glands may discharge into the mouth or in front of its opening. The chelicerae are basically three-segmented pincerlike…
Read More