Green ormer

Green ormer
black and white underwater photo of Haliotis tuberculata coccinea shows its tentacles extended
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
(unranked): clade Vetigastropoda
Superfamily: Haliotoidea
Family: Haliotidae
Genus: Haliotis
Species: H. tuberculata
Binomial name
Haliotis tuberculata
Linnaeus, 1758
Synonyms
  • Haliotis barbouri Foster, 1946[1]

The green ormer (Haliotis tuberculata) is a northeast Atlantic and Mediterranean species of sea snail, a coastal marine gastropod mollusc in the family Haliotidae, the abalones or ormer snails.[2]

The flesh of the green ormer is prized as a delicacy, and this has led to a decline in its population in some areas.

Drawing of a live specimen of Haliotis tuberculata; right side view: d, foot; i, tentacular process of the mantle, passing through the shell-foramina

Taxonomy

Haliotis barbouri Foster, 1946 is a synonym for Haliotis varia.[3][4]

According to the World Register of Marine Species (WoRMS) the following subspecies are recognized:[5]

A shell of Haliotis tuberculata

Shell description

The shell of this species grows as large as 10 cm (3.9 in) in length and 6.5 cm (2.6 in) in width. This flattened, oval shell is an ear-shaped spiral with a mottled outer surface. At the bottom margin of the shell, there is a curving row of five to seven slightly raised respiratory apertures, through which the mantle extends with short, exhalant siphons. As the animal and the shell grow, new holes are formed and the older holes are sealed off. These holes collectively make up what is known as the selenizone, which forms as the shell grows. The inner surface of the shell has a thick layer of iridescent mother-of-pearl.

The large and muscular foot has numerous tentacles at the epipodium (the lateral grooves between the foot and the mantle).

Distribution

A Green ormer in captivity.

This species occurs on rocky shores in European waters from the Mediterranean Sea as far north as the Channel Islands;[6] elsewhere in the Atlantic Ocean it occurs off the Canary Islands and West Africa.

Feeding habits

The green ormer grazes on algae, especially sea lettuce. It breeds in summer, via external fertilisation.

Human use

In the Channel Islands

Ormers are considered a great delicacy in the British Channel Islands. Overfishing has led to a dramatic depletion in numbers since the latter half of the 19th century.

"Ormering" is now strictly regulated in order to preserve stocks. The gathering of ormers is now restricted to a number of "ormering tides", from January 1 to April 30, which occur on the full or new moon and two days following that. No ormers may be taken from the beach that are under 80 mm in shell length. Gatherers are not allowed to wear wetsuits or even put their heads underwater. Any breach of these laws is a criminal offence which can lead to a fine of up to £5,000 or six months in prison.

The demand for ormers is such that they led to the world's first underwater arrest, when a Mr. Kempthorne-Leigh of Guernsey was illegally diving for ormers, and was arrested by a police officer in full diving gear.

References

  1. ↑ Foster R. W. (1946). "The family Haliotidae in the Western Atlantic". Johnsonia 2: 37-40.
  2. ↑ Bouchet, P.; Gofas, S. (2012). Haliotis tuberculata Linnaeus, 1758. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=140059 on 2013-02-05
  3. ↑ Haliotis varia Linnaeus, 1758 Not found in the Western Atlantic. Malacolog Version 4.1.1. A Database of Western Atlantic Marine Mollusca. accessed 23 October 2009
  4. ↑ ABMAP. Alphabetical List of All Taxa. The Abalone mapping project. accessed 23 October 2009.
  5. ↑ WoRMS (2010). Haliotis tuberculata Linnaeus, 1758. In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=140059 on 2010-09-05
  6. ↑ Oliver, A.P.H. (2004). Guide to Seashells of the World. Buffalo: Firefly Books. 22.
Wikimedia Commons has media related to Haliotis tuberculata.
This article is issued from Wikipedia - version of the 11/27/2015. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.