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(invertebrate zoology)
A forked process as the last abdominal segment of certain crustaceans, and as part of the spring in collembolans.



special organs in some insects and crustaceans.

(1) A part of the internal chitinous skeleton of an insect thorax, also known as apophysis. The furca projects into the body in the form of a furcate outgrowth (on the ventral side of the thoracic segments), to which muscle tendons are attached.

(2) A springing organ of insects of the order Collembola, also known as furcula. The furca consists of a pair of out-growths grown together at their base on the ventral side of the fourth abdominal segment. When at rest these outgrowths are folded under the abdomen and secured to a special outgrowth on the third abdominal segment. The furca can unfold downward and backward with force, and when it strikes the ground, it can propel the insect into the air.

(3) A pair of appendages at the end of the last abdominal segment in some crustaceans, such as copepods.

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References in periodicals archive ?
A) Right antenna (A2) (ap = adhesion pad), postantennal process (PAP), maxillule (MX1) and postoral process (POP), ventral; B) Left mandible, posterior; C) Right maxilla, anterior; D) Right maxilliped, anterior; E) Sternal furca, ventral.
Metafurcaesterno de A: Cotophoenissa dibapha (af: apice de la furca, tf: tallo de la furca, ma: membrana del apice y fbf: forma del brazo de la furca) B: Tetracis chilenaria, C: S.
furca were performed to show numerical relationships between these species but not to infer predator-prey or competition relationships.
Sangrado al sondaje, bolsa periodontal con mas de 7 mm, perdida de union mayor a 4 mm, movilidad del diente de 2 o 3 y grado de afeccion de furca de 2 o 3.
O preenchimento de defeitos de furca classe II com enxertos ou biomateriais nao contribuiu para uma maior quantidade de tecidos regenerados, sendo frequente a ocorrencia de anquilose e reabsorcao da raiz dentaria.
9) y progresivamente reduccion de la imagen radiolucida de la zona de furca (Fig.
By modifying the water depth in order that Triops have the possibility of carrying out small swimming ways, Trusheim obtained trackways without the furca trace and in which there is an orientation change of the "legs prints" from perpendicular to oblique with the median axis (Fig.
To a much lesser degree, hook-and-line fishing also transferred to the western fishing grounds, targeting high-value off-reef species (Aphareus furca [Lutjanidae]).
As the second Earl of Bridgewater, the Elder Brother became a staunch royalist and wrote in his copy of Defensio Prima, "Liber igni, Author furca, dignissimi" ("The book is most deserving of burning, the author of the gallows').
But he had been crushing me slowly, and when we started to argue on the top of the Furca Pass he was perhaps nearer a success than either he or I imagined.
One unique feature of most (but not all) species of springtails is the presence of a forked appendage--called a furca or furcula--attached to the fourth abdominal segment.
But, to misquote Horace's famous line about Nature, historiam expellas furca, tamen usque recurret: chase history out with a pitchfork and it comes climbing back in through the window.