Zoology Workshop: A Study Guide - T. A. Dauda 2014

Multicellular Animals
Arthropods
Subphylum Chelicerata

General characteristics

Chelicerates comprise about 40,000 species of predominantly terrestrial Arthropods. The earliest chelicerates were aquatic animals. A distinctive feature of chelicerates is the reduction of antennules, which are appendages of the HEAD lobe (acron). The first pair of cephalothoracic appendages is modified into chelicerae, used for grinding and crushing prey. The second pair, the pedipalps, differs less from the subsequent walking legs and serves sensory and often grasping Functions.

The subphylum Chelicerata includes three classes: Xiphosura (horseshoe crabs), Gigantostraca (eurypterids), and Arachnida (arachnids).

This textbook will focus exclusively on Representatives of the Class Arachnida.



Last update: 13/08/2026

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