Editing Cockle (bivalve) (section)

{{Short description|Family of edible marine bivalve molluscs}}
{{use dmy dates |date=August 2022}}
{{Automatic taxobox
| fossil_range = {{fossil range|Late Triassic|recent|Late [[Triassic]] – Present<ref name="SCHNEIDER 1995 pp. 321–346">{{cite journal | last=Schneider | first=Jay A. | title=Phylogeny of the Cardiidae (Mollusca, Bivalvia): Protocardiinae, Laevicardiinae, Lahilliinae, Tulongocardiinae subfam. n. and Pleuriocardiinae subfam. n. | journal=Zoologica Scripta | publisher=Wiley-Blackwell | volume=24 | issue=4 | year=1995 | issn=0300-3256 | doi=10.1111/j.1463-6409.1995.tb00478.x | pages=321–346| s2cid=86183611 }}</ref>}}
| image = Coques.jpg
| image_caption = Live specimens of  ''[[Cerastoderma edule]]'' from [[France]]
| taxon = Cardiidae
| authority = [[Jean-Baptiste Lamarck|Lamarck]], 1809
| display_parents = 2
| subdivision_ranks = Subfamilies
| subdivision =
*[[Cardiinae]]
*[[Clinocardiinae]]
*[[Fraginae]]
*[[Laevicardiinae]]
*[[Lahilliinae]]
*[[Lymnocardiinae]]
*[[Orthocardiinae]]
*[[Protocardiinae]]
*[[Trachycardiinae]]
*[[Tridacninae]]
| synonyms = Lymnocardiidae
}}

A '''cockle''' is an edible marine [[Bivalvia|bivalve mollusc]]. Although many small edible bivalves are loosely called cockles, [[wikt:stricto sensu#Phrase|true]] cockles are species in the family '''Cardiidae'''.<ref name="WoRMS">[https://www.marinespecies.org/aphia.php?p=taxdetails&id=229 >MolluscaBase eds. (2022). MolluscaBase. Cardiidae Lamarck, 1809. Accessed through: World Register of Marine Species on 2022-02-09]</ref>

True cockles live in sandy, sheltered beaches throughout the world. The distinctive rounded shells are bilaterally symmetrical, and are [[Heart (symbol)|heart]]-shaped when viewed from the end. Numerous radial, evenly spaced ribs are a feature of the shell in most but not all [[genus|genera]] (for an exception, see the genus ''[[Laevicardium]]'', the egg cockles, which have very smooth shells).

The shell of a cockle is able to close completely (i.e., there is no "gap" at any point around the edge).  Though the shell of a cockle may superficially resemble that of a [[scallop]] because of the ribs, cockles can be distinguished from scallops morphologically in that cockle shells lack "auricles" (triangular ear-shaped protrusions near the hinge line) and scallop shells lack a [[pallial sinus]].  Behaviorally, cockles live buried in sediment, whereas scallops either are free-living and will swim into the water column to avoid a predator, or in some cases live attached  by a [[byssus]] to a [[substrate (biology)|substrate]].

The [[mantle (mollusc)|mantle]] has three apertures (inhalant, exhalant, and pedal) for siphoning water and for the foot to protrude.  Cockles typically burrow using the foot, and feed by filtering [[plankton]] from the surrounding water. Cockles are capable of "jumping" by bending and straightening the foot. As is the case in many bivalves, cockles display [[gonochorism]] (the sex of an individual varies according to conditions),<ref>{{cite web |url=http://www.reservebaiedesaintbrieuc.com/IMG/pdf/publication/etudes_scientifiques/Synthesis_Europeen_cockle.pdf |title=Synthesis on biology of Common European Cockle (Cerastoderma edule |publisher=Reservebaiedesaintbrieuc.com |access-date=2012-10-13 }}{{dead link|date=August 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> and some species reach maturity rapidly.

The common name "cockle" is also given by seafood sellers to a number of other small, edible marine bivalves which have a somewhat similar shape and sculpture, but are in other families such as the [[Veneridae]] (Venus clams) and the [[ark clam]]s ([[Arcidae]]). Cockles in the family Cardiidae are sometimes referred to as "true cockles" to distinguish them from these other species.