''Jassa falcata'', commonly known as scud, is a tube-dwelling amphipod.

Ecology

''Jassa falcata'' constructs tubes of

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. It is a fouling organism, growing on the bottoms of ships and slowing them down. ''J. falcata'' forms dense mats or nests. The male and the female live in different tubes. ''J. falcata'' feeds generally on hydroid growth on the bottom of rafts and ships. It is generally a suspension feeder normally found on sediment areas.

Description

Amphipods have two pairs of antennae. In ''J. falcata'' the first antennae have two-segmented

flagella A flagellum (; ) is a hairlike appendage that protrudes from certain plant and animal sperm cells, and from a wide range of microorganisms to provide motility. Many protists with flagella are termed as flagellates. A microorganism may have f ...

and are shorter and more slender than the second antennae. Males are 7–13 mm long and females are 6–12 mm. Colours vary but are usually yellow-grey with brown, red or black patches depending on the colour of the habitat.

Distribution

''Jassa falcata'' is found on all British coasts. It has also been reported in several sites around the coast of Ireland.

References

{{Taxonbar, from=Q3934099 Corophiidea Crustaceans of the Atlantic Ocean Crustaceans described in 1808 Taxa named by George Montagu (naturalist)