stylet

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Figure 1: The heads of stylet-feeding nematodes.

stylet

biology

Also known as: spear

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July 14, 2026

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Figure 1: The heads of stylet-feeding nematodes. — Figure 1: The heads of stylet-feeding nematodes.

A stylet is a slender, pointed, and often rigid organ or appendage. In biology, it commonly refers to the piercing mouthparts of certain animals, particularly insects.1

In insects like mosquitoes, the mandibles and maxillae are modified into slender stylets that form a bundle used for piercing skin and entering blood vessels. The labium then acts as a sheath for these stylets. Similarly, in heteropterans (true bugs), four stylets, formed from modified mandibles and maxillae, lie within a troughlike labium. These stylets create two tubular canals: one for drawing fluids and another for injecting digestive or other fluids into a food source.23

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cirripede
Reproduction and life cycles
…is completed, a hollow, ventral stylet is, depending upon the species, forced either directly into the host or into the host after passing through one of the cyprid’s first antennae. Once in the host’s body, the cells and organ rudiments migrate into a central position beneath the gut, where they…
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…is completed, a hollow, ventral stylet is, depending upon the species, forced either directly into the host or into the host after passing through one of the cyprid’s first antennae. Once in the host’s body, the cells and organ rudiments migrate into a central position beneath the gut, where they…
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heteropteran
Mouthparts
…labium in which lie four stylets; these are modified mandibles and maxillae. Each of the hairlike maxillae has two major grooves plus minor grooves and ridges along its median surface. When brought together and locked by the minor grooves and ridges, the two major grooves form the left and right…
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…labium in which lie four stylets; these are modified mandibles and maxillae. Each of the hairlike maxillae has two major grooves plus minor grooves and ridges along its median surface. When brought together and locked by the minor grooves and ridges, the two major grooves form the left and right…
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plant disease
Mode of nematode attack
…mouthpart called a spear or stylet. The nematode pushes the stylet into plant cells and injects a liquid containing enzymes, which digest plant cell contents. The liquefied contents are then sucked back into the nematode’s digestive tract through the stylet. Nematode feeding lowers natural resistance, reduces vigour and yield of…
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…mouthpart called a spear or stylet. The nematode pushes the stylet into plant cells and injects a liquid containing enzymes, which digest plant cell contents. The liquefied contents are then sucked back into the nematode’s digestive tract through the stylet. Nematode feeding lowers natural resistance, reduces vigour and yield of…
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tardigrade
…individual plant cells with their stylets (spearlike structures near the mouth) and then sucking out the cell contents. A few tardigrades are predatory carnivores. Tardigrades may reproduce sexually or through asexual reproduction (by means of parthenogenesis or through self-fertilization [hermaphroditism]). Eggs are discharged either into the posterior end of the…
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…individual plant cells with their stylets (spearlike structures near the mouth) and then sucking out the cell contents. A few tardigrades are predatory carnivores. Tardigrades may reproduce sexually or through asexual reproduction (by means of parthenogenesis or through self-fertilization [hermaphroditism]). Eggs are discharged either into the posterior end of the…
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