Editing Abalone (section)

==Description==
[[Image:AbaloneInside.jpg|thumb|left|The [[Iridescence|iridescent]] surface inside a [[red abalone]] shell from [[Northern California]]. [[Quarter (United States coin)|The US coin (quarter)]] is {{cvt|0.955|in|order=flip|disp=or}} in diameter]]

Most abalone vary in size from {{convert|20|mm|in|1|abbr=on}} (''[[Haliotis pulcherrima]]'') to {{convert|200|mm|in|0|abbr=on}}. The largest species,  ''[[Haliotis rufescens]]'', reaches {{convert|300|mm|in|abbr=on}}.<ref>{{harvnb|Hoiberg|1993|p=7}}</ref>

The shell of abalone is [[wikt:convex|convex]], rounded to oval in shape, and may be highly arched or very flattened. The shell of the majority of species has a small, flat [[Spire (mollusc)|spire]] and two to three [[Whorl (mollusc)|whorls]]. The last whorl, known as the [[body whorl]], is [[wikt:auriform|auriform]], meaning that the shell resembles an ear, giving rise to the common name "ear shell". ''[[Haliotis asinina]]'' has a somewhat different shape, as it is more elongated and distended. The shell of ''Haliotis cracherodii cracherodii'' is also unusual as it has an [[wikt:ovate|ovate]] form, is [[wikt:imperforate|imperforate]], shows an [[wikt:exsert|exserted]] spire, and has prickly ribs.

A [[mantle (mollusc)|mantle]] cleft in the shell impresses a groove in the shell, in which are the row of holes characteristic of the genus. These holes are respiratory apertures for venting water from the gills and for releasing sperm and eggs into the water column.<ref name=Anderson/> They make up what is known as the [[selenizone]], which forms as the shell grows. This series of eight to 38 holes is near the anterior margin. Only a small number is generally open. The older holes are gradually sealed up as the shell grows and new holes form. Each species has a typical number of open holes, between four and 10, in the selenizone. An abalone has no [[Operculum (gastropod)|operculum]]. The [[Aperture (mollusc)|aperture]] of the shell is very wide and [[wikt:nacreous|nacreous]].<ref name=Anderson>{{cite web |url=http://www.marinebio.net/marinescience/06future/abintro.htm |title=Abalone Introduction |author=Anderson, Jenny |year=2003 |work=Marine Science |accessdate=10 March 2021 }}</ref>

The exterior of the shell is striated and dull. The color of the shell is very variable from species to species, which may reflect the animal's diet.<ref name=MtSS /> The iridescent [[nacre]] that lines the inside of the shell varies in color from silvery white, to pink, red and green-red to deep blue, green to purple.

The animal has [[wikt:fimbriated|fimbriated]] head lobes and side lobes that are fimbriated and [[Cirrus (biology)|cirrated]]. The [[radula]] has small median teeth, and the lateral teeth are single and beam-like. They have about 70 [[uncini]], with [[wikt:denticulated|denticulated]] hooks, the first four very large. The rounded foot is very large in comparison to most molluscs. The soft body is coiled around the [[Columella (gastropod)|columellar muscle]], and its insertion, instead of being on the columella, is on the middle of the inner wall of the shell. The [[gill]]s are symmetrical and both well developed.<ref name="Tryon">{{harvnb|Tryon|1880|p=41}}</ref>

These snails cling solidly with their broad, muscular foot to rocky surfaces at [[Sublittoral zone|sublittoral]] depths, although some species such as ''[[Haliotis cracherodii]]'' used to be common in the [[intertidal zone]]. Abalone reach maturity at a relatively small size. Their [[fecundity]] is high and increases with their size, laying from 10,000 to 11 million eggs at a time. The [[spermatozoa]] are [[wikt:filiform|filiform]] and pointed at one end, and the anterior end is a rounded head.<ref name="Tryon1">{{harvnb|Tryon|1880|p=46}}</ref>