''Tridacna crocea'', the boring clam, crocus clam, crocea clam or saffron-coloured clam, is a species of
bivalve
Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, bival ...
in the
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
Cardiidae
A cockle is an edible marine bivalve mollusc. Although many small edible bivalves are loosely called cockles, true cockles are species in the family Cardiidae. MolluscaBase eds. (2022). MolluscaBase. Cardiidae Lamarck, 1809. Accessed through: W ...
. It is native to the Indo-Pacific region. It is occasionally found in the aquarium trade
[Huelsken, T., Keyse, J., Liggins, L., Penny, S., Treml, E.A., Riginos, C. (2013) A Novel Widespread Cryptic Species and Phylogeographic Patterns within Several Giant Clam Species (Cardiidae: Tridacna) from the Indo-Pacific Ocean. PLoS ONE]
DOI: 10.1371/journal.pone.0080858
where it is often simply referred to as ''crocea''.
Description
The boring clam is the smallest clam in the
subfamily
In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end subfamily botanical names with "-oideae", and zoologi ...
Tridacninae
Tridacninae, common name, the giant clams, is a Taxonomy (biology), taxonomic family (biology), subfamily of very large saltwater clams, marine (ocean), marine bivalve molluscs in the family Cardiidae, the cockles.
Description
This subfamily con ...
and grows to a maximum shell size of .
It has two, thick valves joined by a hinge which is typically between a third and less than a half of the width of the shell. Typically shells are slightly to moderately elongate, and the animal is strongly inflated, especially near the hinge. The upper valve has six to ten flattish folds which interlock at the margin with similar folds on the lower valve so that they can clamp together and the shell can close tightly. The lower valve has slits through which the
byssal threads emerge which secure the animal to the seabed. This clam burrows into the
substrate and this process tends to wear away the outer surface of the valves and smooth them off. They also may become distorted by burrowing into substrates of uneven hardness.
[
The colour of the valves is generally greyish-white, sometimes with a hint of pink-orange, yellow or orange colour -this colouration can form a band near the top margin, especially on the interior surface. The mantle, the soft body wall which covers the animal's internal organs, projects from between the valves when they are open and is brightly coloured. It can be various shades of blue, green, purple, gold, orange or brown, often patterned with spots, stripes or squiggles. It has many small protrusions on the exposed surface and a line of simple eyes near the margin. The inhalent siphon, through which water is drawn into the shell, is surrounded by many small ]tentacle
In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one or more pairs. Anatomically, the tentacles of animals work main ...
s and the exhalent siphon is often long and tubular.[
Image:Boring giant clam.jpg
Image:Tridacna crocea.jpg
Image:Tridacna crocea 01 by Line1.jpg
]
Distribution and habitat
The boring clam is native to the Indo-Pacific. Its range extends from Malaysia
Malaysia ( ; ) is a country in Southeast Asia. The federation, federal constitutional monarchy consists of States and federal territories of Malaysia, thirteen states and three federal territories, separated by the South China Sea into two r ...
, Vietnam
Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making i ...
and Japan
Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...
to Indonesia
Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...
, the Philippines
The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no),
* bik, Republika kan Filipinas
* ceb, Republika sa Pilipinas
* cbk, República de Filipinas
* hil, Republ ...
, Palau
Palau,, officially the Republic of Palau and historically ''Belau'', ''Palaos'' or ''Pelew'', is an island country and microstate in the western Pacific. The nation has approximately 340 islands and connects the western chain of the Caro ...
, New Guinea
New Guinea (; Hiri Motu
Hiri Motu, also known as Police Motu, Pidgin Motu, or just Hiri, is a language of Papua New Guinea, which is spoken in surrounding areas of Port Moresby (Capital of Papua New Guinea).
It is a simplified version of ...
, Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
, the Solomon Islands
Solomon Islands is an island country consisting of six major islands and over 900 smaller islands in Oceania, to the east of Papua New Guinea and north-west of Vanuatu. It has a land area of , and a population of approx. 700,000. Its capita ...
and Vanuatu
Vanuatu ( or ; ), officially the Republic of Vanuatu (french: link=no, République de Vanuatu; bi, Ripablik blong Vanuatu), is an island country located in the South Pacific Ocean. The archipelago, which is of volcanic origin, is east of no ...
. At one time it was known from Guam
Guam (; ch, Guåhan ) is an organized, unincorporated territory of the United States in the Micronesia subregion of the western Pacific Ocean. It is the westernmost point and territory of the United States (reckoned from the geographic cent ...
and the Northern Mariana Islands
The Northern Mariana Islands, officially the Commonwealth of the Northern Mariana Islands (CNMI; ch, Sankattan Siha Na Islas Mariånas; cal, Commonwealth Téél Falúw kka Efáng llól Marianas), is an unincorporated territory and commonw ...
but it may now be locally extinct
Local extinction, also known as extirpation, refers to a species (or other taxon) of plant or animal that ceases to exist in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinct ...
in these locations. Its typical habitat is embedded in massive corals.[
]
References
* Dautzenberg P. (1929). Contribution à l'étude de la faune de Madagascar: Mollusca marina testacea. Faune des colonies françaises, 3(4): 321-636, pls 4-7. Société d'Editions géographiques, maritimes et coloniales, Paris.
* Liu, J.Y. uiyu(ed.). (2008). Checklist of marine biota of China seas. China Science Press. 1267 pp.
External links
*
Lamarck (J.-B. M.) de. (1819). Histoire naturelle des animaux sans vertèbres. Tome 6(1): vi + 343 pp. Paris: published by the author.
Reeve, L. A. (1862). Monograph of the genus Tridacna. In: Conchologia Iconica, or, illustrations of the shells of molluscous animals, vol. 14, pl. 1-8 and unpaginated text. L. Reeve & Co., London.
Poorten, J.J. ter, 2009. The Cardiidae of the Panglao Marine Biodiversity Project 2004 and the Panglao 2005 Deep-Sea Cruise with descriptions of four new species (Bivalvia). Vita Malacologica 8: 9-96
Iredale, T. (1937). Mollusca. In: Whitley, G. P. (ed). Middleton and Elizabeth Reefs, South Pacific Ocean. Australian Zoologist. 8(4): 232-261, pls 15-17
{{Commons, Tridacna crocea
crocea
Fauna of Timor
Bivalves described in 1819
Taxonomy articles created by Polbot