What are polychaetes?

Answer 1

The

Polychaeta

or

polychaetes

are a class of

annelid worms, generally marine. Each body segment has a pair of fleshy protrusions called

parapodia that bear many bristles, called

chaetae, which are made of

chitin. Indeed,

polychaetes

are sometimes referred to as bristle worms. More than 10,000 species are described in this class. Common representatives include the

lug worm (

Arenicola

marina) and the

sandworm or

clam worm

Nereis

.

Polychaetes

as a class are robust and widespread, with species that live in the coldest ocean temperatures of the

abyssal plain, to forms which tolerate the extreme high temperatures near

hydro-thermal

vents.

Polychaetes

occur throughout the Earth's oceans at all depths, from forms that live as

plankton near the surface, to a 2--3 cm specimen (still unclassified) observed by the robot ocean probe

Nereus at the bottom of the

Challenger Deep, the deepest spot in the Earth's

oceans.Only

168 species (less than 2% of all

polychaetes)

are known from

freshwater.

Answer 2

Algae eaters eat the polychaete worms.