
Forcipules are the modified, pincer-like,
front legs of
centipede
Centipedes (from New Latin , "hundred", and Latin , " foot") are predatory arthropods belonging to the class Chilopoda (Ancient Greek , ''kheilos'', lip, and New Latin suffix , "foot", describing the forcipules) of the subphylum Myriapoda, an ...
s that are used to inject
venom
Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a ...
into prey.
They are the only known examples of front legs acting as venom injectors.
Nomenclature
Forcipules go by a variety of names in both scientific and colloquial usages. They are sometimes known as poison claws or jaw legs, referencing their evolution from maxillipeds, a term which they are also sometimes known by in the context of centipedes (maxillipeds, maxillipedes). Other names include toxicognaths (from ''toxic'' + the
Greek
Greek may refer to:
Greece
Anything of, from, or related to Greece, a country in Southern Europe:
*Greeks, an ethnic group.
*Greek language, a branch of the Indo-European language family.
**Proto-Greek language, the assumed last common ancestor ...
''
gnathos'', jaw), prehensors, telopodites, and forcipulae (singular forcipula). The term forcipule references their similarity with
forceps
Forceps (plural forceps or considered a plural noun without a singular, often a pair of forceps; the Latin plural ''forcipes'' is no longer recorded in most dictionaries) are a handheld, hinged instrument used for grasping and holding objects. Fo ...
.
Anatomy, systematics, and variation

Forcipules evolved from the
maxillipeds, meaning the front legs of an arthropod, of centipedes'
last common ancestor
In biology and genetic genealogy, the most recent common ancestor (MRCA), also known as the last common ancestor (LCA) or concestor, of a set of organisms is the most recent individual from which all the organisms of the set are descended. The ...
, believed to be somewhat
Scutigeromorph-like. They were initially leg-like, then progressed into a more pincer or claw-like shape, as seen today, and restricted to horizontal movement.
The forcipules of modern Scutigeromorphs are the most significantly different in shape: they are more leg-like, and cannot hold prey like they are used among other orders- they are used for
envenomation
Envenomation is the process by which venom is injected by the bite or sting of a venomous animal.
Many kinds of animals, including mammals (e.g., the northern short-tailed shrew, ''Blarina brevicauda''), reptiles (e.g., the king cobra), spide ...
only, making their use more comparable to a knife than a pincer.
References
{{Arthropod-anatomy-stub
Myriapod anatomy