''Amphiporus lactifloreus'' is a species of ribbon worm in the phylum

Nemertea Nemertea is a phylum of animals also known as ribbon worms or proboscis worms, consisting of 1300 known species. Most ribbon worms are very slim, usually only a few millimeters wide, although a few have relatively short but wide bodies. Many h ...

. It is found on the lower shore, under stones, in shingle and amongst the fronds of

seaweed Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of '' Rhodophyta'' (red), ''Phaeophyta'' (brown) and ''Chlorophyta'' (green) macroalgae. Seaweed species such as ...

Distribution

This worm is found round the coasts of north west

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

, the

Mediterranean Sea The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the ea ...

, the

Gulf of Maine The Gulf of Maine is a large gulf of the Atlantic Ocean on the east coast of North America. It is bounded by Cape Cod at the eastern tip of Massachusetts in the southwest and by Cape Sable Island at the southern tip of Nova Scotia in the northeast ...

and

Cobscook Bay Cobscook Bay is located in Washington County in the state of Maine. It opens into Passamaquoddy Bay, within the Bay of Fundy. Cobscook Bay is immediately south of the island city of Eastport, the main island of which (Moose Island) straddles the ...

. It is common round the coasts of Britain and Ireland.

Description

Like other ribbon worms, ''A. lactifloreus'' is not divided into segments but is smooth and contractile. It is up to eight centimetres long with a head slightly broader than the body. The eyes are in four groups, two rows on either side of the front of the head and two more central clusters further back. There is a proboscis which can be extended forward from an opening above the mouth and which can be as long as the body and it is armed with a needle-like stylet. The neck is slightly constricted. The body is rounded above and flattened below and has a flattened tail with a rounded end. The general colour is whitish or pale pink and translucent. There are two small deeper pink patches at the back of the head. The gut can be seen as a thread-like, dark coloured, irregular line down the centre of the body.John Barrett and C M Young, ''Collins Pocket Guide to the Sea Shore'' (1958) p.48

Habitat

This worm is locally abundant on fairly clean sandy or gravelly sediments from just below the zone where ''

Pelvetia canaliculata ''Pelvetia canaliculata'', the channelled wrack, is a very common brown alga (Phaeophyceae) found on the rocks of the upper shores of Europe. It is the only species remaining in the monotypic genus ''Pelvetia''. In 1999, the other members of this ...

'' grows down to depths of 250 metres. It is also found amongst shell debris, on ''

Laminaria ''Laminaria'' is a genus of brown seaweed in the order Laminariales (kelp), comprising 31 species native to the north Atlantic and northern Pacific Oceans. This economically important genus is characterized by long, leathery laminae and relativ ...

'', ''

Fucus ''Fucus'' is a genus of brown algae found in the intertidal zones of rocky seashores almost throughout the world. Description and life cycle The thallus is perennial with an irregular or disc-shaped holdfast or with haptera. The erect portion o ...

'' and ''

Ascophyllum ''Ascophyllum nodosum'' is a large, common cold water seaweed or brown alga (Phaeophyceae) in the family Fucaceae, being the only species in the genus ''Ascophyllum''. It is a seaweed that only grows in the northern Atlantic Ocean, also known in ...

'' and, less commonly, in silty or muddy areas. It is fairly tolerant of fluctuating salinity.Marine species identification portal
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Biology

Movement is performed by small waves of muscular contraction that flow along the body from tail to head. Several waves may occur simultaneously and the worm glides forward slowly and smoothly, the swellings running evenly along the body. It is carnivorous, either sucking the body juices of its prey or swallowing the whole animal. It feeds on

protozoan Protozoa (singular: protozoan or protozoon; alternative plural: protozoans) are a group of single-celled eukaryotes, either free-living or parasitic, that feed on organic matter such as other microorganisms or organic tissues and debris. Histo ...

s, other small creatures and prey of a size up to its own. The sexes are distinct and fertilisation is external.

Asexual reproduction Asexual reproduction is a type of reproduction that does not involve the fusion of gametes or change in the number of chromosomes. The offspring that arise by asexual reproduction from either unicellular or multicellular organisms inherit the fu ...

also occurs by fragmentation. When handled, this worm easily breaks into pieces.

References

{{Taxonbar, from=Q2855234 Monostilifera Animals described in 1828