silk gland

animal anatomy

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Last updated

July 13, 2026

Quick Summary

A silk gland is an animal anatomy feature that produces a fluid which hardens into silk when exposed to air. In insects, these are often enlarged salivary glands in larvae used to spin cocoons. For spiders, silk glands are located in the abdomen and open through spinnerets, producing filaments for webs or wrapping prey.12

Spiders are particularly specialized in silk production, with different glands creating various types of silk for specific purposes, such as draglines, prey wrapping, or egg sacs. Spider silk is a protein called fibroin, known for its high tensile strength and elasticity.2

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spider
Silk
…have only two types of silk glands, but orb weavers have at least seven, each of which produces a different kind of silk; e.g., aciniform glands produce silk for wrapping prey, ampullate glands produce the draglines and frame threads, and cylindrical glands produce parts of the egg sac. Epigastric silk…
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…have only two types of silk glands, but orb weavers have at least seven, each of which produces a different kind of silk; e.g., aciniform glands produce silk for wrapping prey, ampullate glands produce the draglines and frame threads, and cylindrical glands produce parts of the egg sac. Epigastric silk…
Read More