ricinuleid

arachnid order

Also known as: Ricinulei

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The Information Architects of Encyclopaedia Britannica

Last updated

July 13, 2026

Quick Summary

Ricinuleids, also known as hooded tickspiders, are a small order of arachnids. They are characterized by an oval, hard body and a distinctive movable hood that folds over their mouthparts. These arachnids are primarily found in tropical regions and have a six-legged larval form. The order Ricinulei is part of the class Arachnida, which also includes more familiar creatures like spiders, scorpions, mites, and ticks.123

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arachnid
Annotated classification
Order Ricinulei (ricinuleids) 30 primarily tropical species. Size 8–10 mm; abdomen of 9 segments, last 3 forming taillike pygidium; 6-legged larval form. Subclass Acari, Acarina, or Acarida (mites and ticks)
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Order Ricinulei (ricinuleids) 30 primarily tropical species. Size 8–10 mm; abdomen of 9 segments, last 3 forming taillike pygidium; 6-legged larval form. Subclass Acari, Acarina, or Acarida (mites and ticks)
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arachnid
Body and appendages
Among the spiderlike ricinuleids (order Ricinulei), special copulatory organs are located on the third pair of legs. Some mites, particularly immature individuals, have only two or three pairs of legs.
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Among the spiderlike ricinuleids (order Ricinulei), special copulatory organs are located on the third pair of legs. Some mites, particularly immature individuals, have only two or three pairs of legs.
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