cribellum

anatomy

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June 25, 2026

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The term "cribellum" refers to a specialized spinning organ found in certain spiders. This organ has numerous fine perforations and is located in front of the spider's ordinary spinning organs. Spiders possessing a cribellum are classified as Cribellatae. The calamistrum, a comb-like structure on the hind legs of cribellate spiders, assists in arranging the silk produced by the cribellum. This anatomical feature is specific to certain spider families within the Araneomorphae infraorder.1234

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spider
Silk
…(colulus) or flat plate (cribellum), through which open thousands of minute spigots. Spiders with a cribellum also have a comb (calamistrum) on the metatarsus of the fourth leg. The black widow is one such comb-footed spider (family Theridiidae). The calamistrum combs the silk that flows from the cribellum, producing…
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…(colulus) or flat plate (cribellum), through which open thousands of minute spigots. Spiders with a cribellum also have a comb (calamistrum) on the metatarsus of the fourth leg. The black widow is one such comb-footed spider (family Theridiidae). The calamistrum combs the silk that flows from the cribellum, producing…
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