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(invertebrate zoology)
A filelike ribbon studded with horny or chitinous toothlike structures, found in the mouth of all classes of mollusks except Bivalvia.



an apparatus in mollusks, except bivalves, that rasps off and tears up food. The radula consists of a chitinous basal ribbon that lies on the surface of the tongue, the muscular out growth of the ventral wall of the pharynx. It is covered with cross rows of numerous, up to 75,000, chitinous teeth, the number, shape, and position of which serve as taxonomic criteria. The radula works like a dredge equipped with scoops. Its main function is to allow the mollusk to rasp off the food, which is then swallowed.

References in periodicals archive ?
Phylogenetic significance of the radula in chitons, with special reference to the Cryptoplacoidea (Mollusca: Polyplacophora).
Tetralophozia filiformis (Stephani) urmi, Radula holtii Spruce.
The genus Autocoptis differs from Urocoptis, a Jamaican genus, by characteristics of the juvenile shell and the radula.
While the radula sounds like something from a horror movie, it is in fact found in the mouths of most molluscs, from the giant squid to the garden snail.
These specimens would be difficult to interpret without reference to the much larger Mahto sample, but can now be recognised as among the earliest radulas on record.
The pointy yellow things (right) are individual ammonite teeth, stripped off a structure called a radula that acts like a tongue to get prey into the animal's mouth.
Lopez (2001) senala que Conus es el genero de invertebrados marinos con el mayor numero de especies vivientes, lo que es consecuencia de su gran exito evolutivo, basado principalmente en el sofisticado metodo de alimentacion depredadora que les permite cazar la presa, paralizarla y en muchos casos, engullirla casi instantaneamente utilizando la radula toxoglosa provista de dientes marginales que tienen forma de arpon e inyectan veneno.
cornuarietis may be attributed to the functional morphology of this species, which includes a radula with long canine-like teeth that is efficient at consuming macrophytes (Horne et al.
De estos, 50 se emplearon para la identificacion externa (concha), 50 para la identificacion de la radula y el aparato reproductor, y 50 para observar las formas larvarias de Fasciola hepatica, segun trabajos realizados por Tantalean et al.
The sea snails use a modified tooth called a radula, chewing down long lines of tissue in a fashion similar to mowing a lawn.