In
zoology
Zoology ( , ) is the scientific study of animals. Its studies include the anatomy, structure, embryology, Biological classification, classification, Ethology, habits, and distribution of all animals, both living and extinction, extinct, and ...
, the hypostome can refer to structures in distinct animal groups:
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Hypostome (trilobite)
The hypostome is the hard mouthpart of trilobites found on the ventral side of the cephalon (head). The hypostome can be classified into three types based on whether they are permanently attached to the rostrum or not and whether they are aligne ...
, the ventral mouthpart plate in trilobites
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Hypostome (tick)
The hypostome (also called the maxilla, radula, or Labium (insect), labium) is a Osseous tissue, calcified harpoon-like structure near the mouth area of certain Parasitism, parasitic arthropods including ticks, that allows them to anchor themselv ...
, the barbed attachment structure associated with the mouthparts of parasitic arachnids
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Hypostome (cnidarian), the oral tip surrounded by tentacles in hydrozoan cnidarians
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