Stinger

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For other uses, see Stinger (disambiguation).

1 Zoology
2 Botany
3 See also
4 Sources and references

A stinger (or sting) is a common term for a sharp organ or body part found in various animals and plants that usually delivers some kind of venom (usually piercing the skin of another animal) or an electric shock. A poisonous stinger differs from other piercing organs in that it pierces by its own action, as opposed to e.g., teeth, which pierce by the force of jaws, or thorns, which pierce by the action of the victim.

"Sting" also refers to the wound caused by a stinger, and used as a verb "to sting" is to inflict such a wound.

[edit] Zoology

Wasp stinger, with droplet of venom

The main type of construction of stingers is a sharp organ of offense or defense, especially when connected with a poison gland, and adapted to inflict a wound by piercing; as the caudal sting of a scorpion. Among mammals, the male duck-billed platypus is unique in having a poisonous sting.

The stinger is typically located at the rear of the animal, near the tail (if any). Animals with stingers include bees, wasps, hornets, and scorpions - although the scorpion's stinger is not homologous to that of the other three, but is rather an example of convergent evolution.

In honeybees (and only in honeybees, not in any other bees or wasps), the stinger (a modified ovipositor as in other stinging Hymenoptera) is barbed, and lodges in the flesh of mammals upon use and tears free from the honeybee's body, leading to the honeybee's death within minutes. The stinger has its own ganglion (a mini-brain, essentially) and it continues to saw into the target's flesh and release venom for several minutes. The question of how such a trait could have evolved, when it is of such an obvious disadvantage to the individual, is resolved when one realizes that mammalian predators can easily destroy the entire colony if not repelled; if the colony is destroyed, a worker, being sterile, will die without offspring, so only through defense of the colony can she see to it that her genes are passed on. The barbs ensure that a honeybee's attack is only suicidal if the attacker is a mammal; they can sting other bees (in inter-colony raids) repeatedly. Thus, under natural conditions, the suicidal aspect of the honeybee stinger's barbs only come into play in the event of an attack which threatens to wipe out the entire colony. The stinger of all other bees and wasps is not barbed, and so can be used to sting mammals repeatedly (or, more accurately, to sting mammals and still live to sting another day).

The caudal sting, or spine, of a sting ray is a modified dorsal fin ray.

For creatures such as jellyfish, stinger can refer to the tentacles that carry cnidocytes to capture and paralyze prey.

By extension the term is sometimes applied to the fang (a modified tooth) of a snake. One species of snake, Psammophylax rhombeatus, is even known as skaapsteker (Afrikaans for sheep stinger). It is extremely common in South Africa, and far north along the east as well as west coast

[edit] Botany

A sharp-pointed hollow hair seated on a gland which secrets an acrid fluid, as in nettles. The points of these hairs usually break off in the wound, and the acrid fluid is pressed into it.