Tylorrhynchus heterochetus | |
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Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Annelida |
Clade: | Pleistoannelida |
Subclass: | Errantia |
Order: | Phyllodocida |
Family: | Nereididae |
Genus: | Tylorrhynchus |
Species: | T. heterochetus |
Binomial name | |
Tylorrhynchus heterochetus (Quatrefages, 1866) | |
Tylorrhynchus heterochetus, also known as the Japanese palolo [1] is a species of edible ragworm.
The species can be commonly found in estuaries of the Yellow Sea, East China Sea and South China Sea. Its mature size is circa 5.65 cm. [2] [3]
The worm inhabits the muddy soil of estuaries and rice paddies. During the reproductive season in November and December, the worms swim up to the surface and migrate to sea at high tide. The males will turn to a white milky colour, whereas females will attain a white-green colour. As the worms reach the higher salinity seawater, they will release their gametes and die. [2]
Due to pollution and changes to their natural environments, they are nowadays less numerous, and entirely extinct in some habitats. [2]
The up to 35 cm deep burrows made by the worm in muddy sea beds help to bring oxygen to nitrifying bacteria. [4]
It is eaten as a local delicacy in the Chinese coastal provinces of Guangdong, Fujian and Zhejiang and in Northeast Vietnam. [2] The worm has high nutritional value in protein and fats. [5]
In Vietnam, it is mainly used in a dish called chả rươi, [6] which has been known as a delicacy for centuries, especially in the area of Tứ Kỳ district, Hải Dương province. [7]
As it occurs only during its breeding season, farmers can earn relatively high incomes from harvesting the worms. In some areas, this has resulted in overfishing. [7] [8]
It is also used in traditional Chinese medicine. A study has shown that consumption of the worm has an anti-fatigue effect on mice. [9]
Since the worms are sensitive to changes in their environmental conditions, they are sometimes used by researches to monitor the quality of marine habitats. [10]
The Sipuncula or Sipunculida is a class containing about 162 species of unsegmented marine annelid worms. Sipuncula was once considered a phylum, but was demoted to a class of Annelida, based on recent molecular work.
Polychaeta is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes. Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are made of chitin. More than 10,000 species are described in this class. Common representatives include the lugworm and the sandworm or clam worm Alitta.
Detritivores are heterotrophs that obtain nutrients by consuming detritus. There are many kinds of invertebrates, vertebrates, and plants that carry out coprophagy. By doing so, all these detritivores contribute to decomposition and the nutrient cycles. Detritivores should be distinguished from other decomposers, such as many species of bacteria, fungi and protists, which are unable to ingest discrete lumps of matter. Instead, these other decomposers live by absorbing and metabolizing on a molecular scale. The terms detritivore and decomposer are often used interchangeably, but they describe different organisms. Detritivores are usually arthropods and help in the process of remineralization. Detritivores perform the first stage of remineralization, by fragmenting the dead plant matter, allowing decomposers to perform the second stage of remineralization.
Nereididae are a family of polychaete worms. It contains about 500 – mostly marine – species grouped into 42 genera. They may be commonly called ragworms or clam worms.
Eunicidae is a family of marine polychaetes. The family comprises marine annelids distributed in diverse benthic habitats across Oceania, Europe, South America, North America, Asia and Africa. The Eunicid anatomy typically consists of a pair of appendages near the mouth (mandibles) and complex sets of muscular structures on the head (maxillae) in an eversible pharynx. One of the most conspicuous of the eunicids is the giant, dark-purple, iridescent "Bobbit worm", a bristle worm found at low tide under boulders on southern Australian shores. Its robust, muscular body can be as long as 2 m. Eunicidae jaws are known from as far back as Ordovician sediments. Cultural tradition surrounds Palola worm reproductive cycles in the South Pacific Islands. Eunicidae are economically valuable as bait in both recreational and commercial fishing. Commercial bait-farming of Eunicidae can have adverse ecological impacts. Bait-farming can deplete worm and associated fauna population numbers, damage local intertidal environments and introduce alien species to local aquatic ecosystems.
Alitta virens is an annelid worm that burrows in wet sand and mud. They construct burrows of different shapes They range from being very complex to very simple. Long term burrows are held together by mucus. Their burrows are not connected to each other; they are generally solitary creatures. The spacing between the burrows depends on how readily they can propagate water signals.
Palola viridis, commonly known as the palolo worm, Samoan palolo worm, balolo, wawo, or nyale, is a Polychaeta species from the waters of some of the Pacific islands, including Samoa, Tonga, Fiji, Vanuatu, the Solomon Islands, Papua New Guinea, and the islands of the maritime Southeast Asia.
Gilvossius tyrrhenus is a species of mud shrimp which grows to a length of 70 mm (2.8 in). It lives in burrows in shallow sandy parts of the sea-bed in the Mediterranean Sea and northern Atlantic Ocean. It is the most common thalassinidean in the Mediterranean, and has been used as bait by fishermen for at least 200 years.
Alitta succinea is a species of marine annelid in the family Nereididae. It has been recorded throughout the North West Atlantic, as well as in the Gulf of Maine and South Africa.
Cirratulus cirratus is a species of marine polychaete worm in the family Cirratulidae. It occurs in the littoral and sub-littoral zones of the Atlantic Ocean.
Lanice conchilega, commonly known as the sand mason worm, is a species of burrowing marine polychaete worm. It builds a characteristic tube which projects from the seabed, consisting of cemented sand grains and shell fragments with a fringe at the top.
Abarenicola pacifica or the Pacific lugworm is a large species of polychaete worm found on the west coast of North America and also in Japan. The worms live out of sight in burrows under the sand and produce casts which are visible on the surface.
Osedax frankpressi is a species of bathypelagic polychaete worm that lives on the seabed and sustains itself on the bones of dead whales. It can be found in the East North Pacific Ocean. The specific epithet is named in honor of Frank Press "for his distinguished service to science".
Hediste diversicolor, commonly known as a ragworm, is a polychaete worm in the family Nereididae. It lives in a burrow in the sand or mud of beaches and estuaries in intertidal zones in the north Atlantic. This species is used in research, but its classification is in dispute; in the literature, it is often classified as Nereis diversicolor. Its specific name "diversicolor" refers to the fact that its colour changes from brown to green as the breeding season approaches.
The annelids, also known as the segmented worms, comprise a large phylum called Annelida. The phylum contains over 22,000 extant species, including ragworms, earthworms, and leeches. The species exist in and have adapted to various ecologies – some in marine environments as distinct as tidal zones and hydrothermal vents, others in fresh water, and yet others in moist terrestrial environments.
Scolelepis squamata is a species of polychaete worm in the family Spionidae. It occurs on the lower shore of coasts on either side of the Atlantic Ocean.
Chả rươi is a Vietnamese dish made from the polychaete worm Tylorrhynchus heterochetus; it is a delicacy of some provinces in Northern Vietnam. The dish is prepared from live sand worms, which are put in hot water to remove their tentacles, and then mixed with raw egg. Onions and various spices are added, and the mixture is then fried until it obtains a crispy brown surface.
Eunice aphroditois is a benthic bristle worm of warm marine waters. It lives mainly in the Atlantic Ocean, but can also be found in the Indo-Pacific. It ranges in length from less than 10 cm (4 in) to 3 m (10 ft). Its exoskeleton displays a wide range of colors, from black to purple and more. This species is an ambush predator; it hunts by burrowing its whole body in soft sediment on the ocean floor and waiting until its antennae detect prey. It then strikes with its sharp mandibles. It may also be found among coral reefs.
Streblospio benedicti is a small polychaete native to the Western Atlantic, where its distribution ranges from the Gulf of Saint Lawrence to Venezuela. Sexual maturity is reached at around 9 to 14 weeks and populations and individuals may vary during development. It can be found in the mudflats and soft sediments of estuaries and coastal waters. Its general habitat includes oyster reefs, mangroves, grass beds, marinas, and docks while the tidal range where S. benedicti can be found is subtidal to intertidal. Additionally, S. benedicti can tolerate a broad range of temperatures and salinities. Due to its tolerance of high organic contents, S. benedicti is a pioneer organism of new habitats that it settles in. Furthermore, despite its small size, only reaching a maximum of 20 mm (0.79 in) in length, S. benedicti plays an important role in estuarine food webs as it can reach high population densities and is a substantial grazer of phytoplankton.
Tylorrhynchus is a genus of polychaetes belonging to the family Nereididae. They are also known as ragworms.