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Journal of Comparative Physiology A

, Volume 168, Issue 1, pp 63–73 | Cite as

The giant fiber system in the forelegs (whips) of the whip spider Heterophrynus elaphus Pocock (Arachnida: Amblypygi)

  • Peter Igelmund
  • Gernot Wendler
Article

Summary

The front legs of the whip spider H. elaphus are strongly modified to serve sensory functions. They contain several afferent nerve fibers which are so large that their action potentials can be recorded externally through the cuticle. In recordings from the tarsus 7 different types of afferent spikes were identified; 6 additional types of afferent spikes were discriminated in recordings from the tibia and femur. Most of the recorded potentials could be attributed to identifiable neurons serving different functions. These neurons include giant interneurons and giant fibers from diverse mechanoreceptors such as slit sense organs, trichobothria, and a joint receptor. In the present report these neurons are characterized using electrophysiological and histological methods. Their functions are discussed in the context of the animal's behavior.

Key words

Giant fibers Giant neurons Mechanoreceptors Whip spider 

Abbreviations

GN

giant neuron

S

segment

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Copyright information

© Springer-Verlag 1991

Authors and Affiliations

  • Peter Igelmund
    • 1
  • Gernot Wendler
    • 1
  1. 1.Zoologisches Institut der Universität zu Köln, Lehrstuhl TierphysiologieKölnFederal Republic of Germany

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