Editing Radula (section)

{{Short description|Anatomical structure of mollusks used for eating}}
{{for|the plant genus|Radula (plant)}}
{{Use dmy dates|date=March 2020}}

The '''radula''' ({{IPAc-en|US|ˈ|r|æ|dʒ|ʊ|l|ə}}; {{plural form}}: '''radulae''' or '''radulas''')<ref>
{{cite web|url=http://www.wordswarm.net/mw-2003/radula.html|title=Radula definitions|publisher=wordswarm.net|access-date=2009-10-09}}
</ref> is an anatomical structure used by [[Mollusca|mollusks]] for feeding, sometimes compared to a [[tongue]].<ref>{{cite web|url=http://www.allaboutslugs.com/slug-and-snail-science/slug-anatomy|title=All About Slugs}}</ref> It is a minutely toothed, [[chitin]]ous ribbon, which is typically used for scraping or cutting food before the food enters the [[esophagus]]. The radula is unique to the mollusks, and is found in every class of mollusk except the [[Bivalvia|bivalves]], which instead use cilia, waving filaments that bring minute organisms to the mouth.

Within the [[gastropods]], the radula is used in feeding by both [[herbivore|herbivorous]] and [[carnivore|carnivorous]] [[snail]]s and [[slug]]s. The arrangement of teeth ([[Denticle (tooth feature)|denticles]]) on the radular ribbon varies considerably from one group to another.

In most of the more ancient lineages of gastropods, the radula is used to graze, by scraping [[diatom]]s and other microscopic [[alga]]e off rock surfaces and other substrates.

Predatory marine snails such as the [[Naticidae]] use the radula plus an acidic secretion to bore through the shell of other mollusks. Other predatory marine [[snails]], such as the [[Conidae]], use a [[Cone snail#Harpoon|specialized radular tooth as a poisoned harpoon]]. Predatory [[pulmonate]] land [[slug]]s, such as the [[ghost slug]], use elongated razor-sharp teeth on the radula to seize and devour [[earthworms]]. Predatory cephalopods, such as [[squid]], use the radula for cutting prey.

The introduction of the term "radula" (Latin, "little scraper") is usually attributed to [[Alexander von Middendorff]] in 1847.<ref>{{in lang|de}} von Middendorff A. T. (1847). ''Beiträge zu einer malacozoologia rossica: Chitonen''. St. Petersburg, 151 pp. + plates. [https://books.google.com/books?id=b0U3AQAAMAAJ&q=radula&pg=PA54 p .54].</ref>