Marine Science Chapters


Abalone Species Diversity

Seven species of abalone can be found on the West Coast of North America (red, pink, black, green, white, pinto, and flat). Note that the pinto and threaded abalone were once considered separate subspecies.

Red abalone species ranges
Abalone species ranges on the West Coast of North America. The pinto and threaded are now considered the same species but with a northern and southern shell form that integrates in the area of Central California between the ranges shown in this map. (Map from NASA, ranges added by author (GA) indicating each species' general concentration, not full range.) Visit Daniel Geiger's wonderful ABMAP site for the most recent geographical and scientific information at: .

Abalone have been used in this area since man was first here. The native Americans ate the abalone meat, used the whole shells as bowls, pieces of the shells for fish hooks, scrapers, beads, necklaces and decorations, and even bartered with the shells.

Red abalone outside shell Red abalone inside shell
Red abalone outside of shell (left) and inside of shell (right). (GA images)

Red abalone shell margin
Red abalone shell margin. (GA image)

Red abalone, Haliotis rufescens, are the largest abalone in the world, up to 12.3 inches in shell diameter. This was the main species that was harvested in the California abalone fishery – which no longer exists. It is also the species upon which most of the mariculture interest has been focused both by public and private groups.

Pink abalone outside shell Pink abalone inside shell
Pink abalone outside of shell (left) and inside of shell (right). (GA images)

Pink abalone shell margin
Pink abalone shell margin. (GA image)

Pink abalone, Haliotis corrugata, have a highly corrugated shell margin. Because of this they have an alternate name, the corrugated abalone.

Black abalone outside shell Black abalone inside shell
Black abalone outside of shell (left) and inside of shell (right). (GA images)

Black abalone shell margin
Black abalone shell margin. (GA image)

Black abalone, Haliotis cracherodii, rarely have anything growing on the shell and are often intertidal. Adults have a wide tolerance for various temperatures. This species was the least desired of the North American abalone for food. They are a little tougher and lack the pure white solid part of their meat. With the removal of the sea otter (a major predator on abalone) in southern California during the early 1900s this species could be found stacked on top of each other in the tidepools of southern California until hard hit by disease in the 1980s.

Green abalone outside shell Green abalone inside shell
Green abalone outside of shell (left) and inside of shell (right). (GA images)

Green abalone shell margin
Green abalone shell margin. (GA image)

Green abalone, Haliotis fulgens, are restricted to southern Califonia and Baja Mexico. Its interior is prized by jewelers for its beautiful blue-green luster.

White abalone outside shell White abalone inside shell
White abalone outside of shell (left) and inside of shell (right). (GA images)

White abalone shell margin
White abalone shell margin. (GA image)

White abalone, Haliotis sorenseni, may have the smallest population on the West Coast of North America. It has one of the most tender and flavorful meats of all the abalone species. Currently this species is being maricultured for seed to be placed in the ocean in hopes of bringing this species back to safe population levels.

Pinto abalone, northern form, outside shell Pinto abalone, northern form, inside shell
Pinto abalone, northern form, outside of shell (left) and inside of shell (right). (GA images)

Pinto abalone shell margin
Pinto abalone, northern form, shell margin. (GA image)

Pinto abalone shells lined up
Pinto abalone shells, northern form, lined up to show diversity of color. (GA image)

Pinto abalone, northern form, Haliotis kamtschatkana, are one of the more northern abalone. They have a relatively thin shell and were rarely fished due to their smallish size. NOTE: Threaded abalone, the southern form, were once regarded as a subspecies of the pinto abalone and given the name Haliotis kamtschatkana assimilus while the pinto abalone was Haliotis kamtschatkana kamtschatkana. However, genetic studies in 2005 and 2010 found their tissue to be molecularly identical so they are considered one species, the pinto abalone, with northern and southern shell characteristics.

PINTO ABALONE, SOUTHERN FORM (previously called the threaded abalone)
Pinto abalone, southern form, outside shell Pinto abalone, southern form, inside shell
Pinto abalone, southern form, (previously called the threaded abalone) outside of shell (left) and inside of shell (right). (GA images)

Pinto abalone, southern form, (previously called the threaded abalone) shell margin
Pinto abalone, southern form, (previously called the threaded abalone) shell margin. (GA image)

Threaded abalone shells showing rare orange genetic band
Pinto abalone, southern form, (previously called the threaded abalone) shells showing rare orange genetic band. (GA image)

Pinto abalone, southern form, (previously called the threaded abalone) have a unique genetic characteristic found in 5-10% of the population where there is an orange band running parallel to the open holes. This has nothing to do with feeding. (More uncommonly, the northern form may also have this band.)

Flat abalone outside shell Flat abalone inside shell
Flat abalone outside of shell (left) and inside of shell (right). (GA images)

Flat abalone shell margin
Flat abalone shell margin. (GA image)

Flat abalone shells lined up
Flat abalone shells lined up. (GA image)

Flat abalone, Haliotis walallensis, have a flat shell and are often located in the far reaches of cracks and crevices making them difficult to see. They prefer cooler water than many of the other species and thus are a more northern species. This species is rarely collected for food as it is relatively small.

Common Name # of open holes outside of
inside of
shell margin muscle scar epipodium epipodial tentacles

red abalone 3-4 dull red blue-green red rim present lobed, black black

pink abalone 2-4 green to red pink corrugated present lacy, white black

black abalone 5-9 black white smooth absent lobed, black black

green abalone 5-7 olive green to brown blue-green smooth present lacy, green to brown green

white abalone 3-5 red to brown white and pink smooth absent lacy, beige yellow-green

pinto abalone 3-6 green-brown with white and blue white scalloped absent lacy, green-brown green-brown

threaded abalone 3-6 green with red, white, or brown spots white smooth absent lacy, yellow-brown yellow-brown

flat abalone 4-8 red with white, blue and green purple-pink smooth absent lacy, yellow-green yellow-green

Table information from California State Department of Fish and Game, Marine Resources Leaflet No. 11

Several characteristics can be used to tell the seven abalone species apart. These include the number of open holes, the color of the outside and inside of the shell, the shape of the shell margin, the presence or absence of a muscle scar, the color and description of the epipodium, and the color of the epipodial tentacles.

New Zealand abalone outside of shells New Zealand abalone inside of shells
South Pacific abalone - outside of shells (left) and inside of shells. Shells are Australian black lip abalone (Haliotis rubra), Australian green lip abalone (Haliotis laevigata), and New Zealand's paua (Haliotis iris). (GA images)

Abalone species live in temperate areas all over the world. They share similar shell and body characteristics but each species is unique. Somewhere over 80 species exist worldwide – all found in rocky habitats. Most abalone can be used to make inlay jewelry because of the beautiful mother-of-pearl inside the shell.

 Copyright and Credits
(Revised 29 July 2018)
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