Cerebratulus lacteus,themilky nemerteanormilky ribbon worm,is aproboscis wormin the familyLineidae.This ribbon worm has a wide geographical range on both sides of the northern Atlantic Ocean.[1]
| Cerebratulus lacteus | |
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Scientific classification
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| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Nemertea |
| Class: | Pilidiophora |
| Order: | Heteronemertea |
| Family: | Lineidae |
| Genus: | Cerebratulus |
| Species: | C. lacteus
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| Binomial name | |
| Cerebratulus lacteus (Leidy, 1851)[1]
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| Synonyms[1] | |
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Description
editCerebratulus lacteusgrows to a length of about 120 cm (4 ft) and a width of 22 mm (0.9 in).[1]The head is rounded and flattened, with a pair of cerebral organs and cephalic grooves, but no eyes. The head is not readily distinguishable from the body, which is flattened and gradually tapers towards the tail, where there is a slender caudal cirrus. This worm is usually milky-white in colour but may be pink.[2]
Ecology
editCerebratulus lacteusburrows in muddy sediments into which it can burrow rapidly. It is a voraciouspredatorand has been observed attackingbivalve molluscsand crustaceans.[3]Theproboscisis everted (turned inside out) and the lower half of theAtlantic jackknife clam(Ensis directus) is enveloped. In an effort to escape, the clam works its way out of the sediment and may then be at risk of predation by birds. Soft clams, such asMya arenariaare also attacked. In this case, the ribbonworm inserts the tip of its proboscis through thesiphonand consumes the soft tissues.[4]It is not clear whether the ribbonworm preys on hard clams, but a high abundance of this worm at one location nearPrince Edward Islandwas thought to be responsible for the high mortality among newly transplanted hard clams.[4]
As is the case with other nemertean worms, the sexes are separate in this species and fertilisation is external. Reproduction can also occur byfragmentation,as this worm readily breaks into pieces which can grow into new organisms.[1]
Research
editCerebratulus lacteusproduces several homologouspolypeptidecytotoxinsthat are active in breaking down the membranes of humanred blood cells,as well as severalneurotoxins.These substances are being researched.[5]
Clamshave been identified as a useful subject foraquaculturein Canada. BecauseCerebratulus lacteusis a threat to such activities, research is ongoing into the ribbonworm and what governs its patchy distribution, with a view to being able to better control it.[6]
References
edit- ^abcdeGibson, Raymond (2005)."Cerebratulus lacteus(Leidy, 1851) ".WoRMS.World Register of Marine Species.Retrieved20 September2017.
- ^Bachiller, Alfonso Herrera."Cerebratulus lacteus".Nemerteans from Spain and Portugal(in Spanish).Retrieved20 September2017.
- ^Rothschild, Susan B. (2004).Beachcomber's Guide to Gulf Coast Marine Life: Texas, Louisiana, Mississippi, Alabama, and Florida.Taylor Trade Publications. pp.75–76.ISBN978-1-58979-061-2.
- ^abKraeuter, John Norman; Castagna, Michael (2001).Biology of the Hard Clam.Gulf Professional Publishing. pp.445–446.ISBN978-0-444-81908-6.
- ^Blumenthal, Kenneth M.; Kem, William R. (1980)."Structure and action of heteronemertine polypeptide toxins. Primary structure ofCerebratulus lacteustoxin A-III ".Journal of Biological Chemistry.265(17):3266–3272.
- ^Bourque, Daniel (5 May 2017)."Understanding the distribution of a nemertean predator,Cerebratulus lacteus,in clam flats: implications for control measures ".Fisheries and Oceans, Canada.Retrieved20 September2017.