Dictionary > Chelicera

Chelicera

Definition
noun, plural: chelicerae
Either of the first set of appendages of the chelicerates (e.g. arachnids, horseshoe crabs, etc.)
Supplement
Chelicerates, such as arachnids, sea spiders, and horseshoe crabs, are known for having segmented bodies with paired jointed limbs or appendages. The first pair of these appendages is termed chelicerae, which etymologically means jaws or horns and from where the name of this group is derived.
Chelicera pertains to any of the two in a pair of appendages that arise from segment two of chelicerates. They are typically found ahead of the mouth. Most chelicerae are made up of three sections except for spider chelicerae that are comprised of only two sections. There are three kinds of chelirae: (1) jackknife chelicerae (as seen in Tetrapulmonata species), (2) scissor chelicerae (such as those in Pseudoscorpiones and Solfifugae), and (3) 3-segmented chelate chelicerae (such as those in Scorpiones and Opiliones).1
Certain spiders, particularly the venomous kinds, have chelicerae that contain or are connected to venom glands. These spiders use them to inject venom for protection against a perceived threat or for capturing prey.
Word origin: Ancient Greek khēlḗ (“jawbone”) + kéras (“horn”)
See also:

Reference(s):

1 Rainer F. Foelix (1996). Biology of Spiders (2nd ed.).Oxford University Press.


You will also like...

Buttress roots
Roots

This study guide tackles plant roots in greater detail. It delves into the development of plant roots, the root structur..

DNA carries genes coding for proteins
Genetic Information and Protein Synthesis

Genes are expressed through the process of protein synthesis. This elaborate tutorial provides an in-depth review of the..

Direct and indirect physiologic effects of growth hormone
Animal Growth Hormones

Hormones are produced in the endocrine glands of animals. The pituitary gland and hypothalamus are the most impor..

Freshwater lake ecosystem
Freshwater Producers and Consumers

Freshwater ecosystem is comprised of four major constituents, namely elements and compounds, plants, consumers, and deco..

human respiratory system
Respiration

The human respiratory system is an efficient system of inspiring and expiring respiratory gases. This tutorial provides ..

Cell structure
Cell Structure

A typical eukaryotic cell is comprised of cytoplasm with different organelles, such as nucleus, endoplasmic reticulum, G..

Related Articles...

No related articles found

See all Related Topics