Creature of the week
Spoon worm or Echiuran worm
40-150 mm
JOHN BISSET/Fairfax NZ
WEIRD AND WONDERFUL: Beachgoers were amazed and the seagulls very happy with the appearance of the
creatures at Caroline Bay.
JOHN BISSET/Fairfax NZ
CLOSE UP: Tyson Johns wears gloves to make a close inspection of the creatures.
An invasion of slug-like creatures had beachgoers curious in Timaru today.
Hundreds of the marine life-forms were scattered along Caroline Bay, lying along the sand, and caught in the
debris that has washed up on the bay in recent floods.
The slugs are 4- to 15cm long, move when touched, are quite flexible, and have proved tempting morsels for
dozens of seagulls.
Creature of the week
Spoon worm or Echiuran worm
40-150 mm
The Echiura, or spoon worms, are a small group of marine worms
Description:
Echiurans have a worm-like body with a large flattened proboscis projecting forward from
the head. The body is typically drab in colour, but bright red and green species are known.
The proboscis is a sheet-like structure, rolled around into a cylindrical tube with an open
gutter at the ventral surface. The length of the proboscis varies greatly between species, and
in some species is many times longer than the rest of the body.. Adult echiurans have no trace
of segmentation. Echiruans do not have a distinct respiratory system, absorbing oxygen
through the body wall. do not have any eyes or other distinct sense organs.
Habitat:
Many live in burrows in sand and mud; others live in rock and coral crevices. The majority of
echiurans live in shallow water, but there are also deep sea forms. More than 230 species
have been described.
Echiura at a market in South Korea
wikipedia.org/wiki/Echiura
Diet:
Echiurans are suspension feeders,
projecting their proboscis out of their burrows,
with the gutter projecting upwards. Edible
particles will then settle onto the proboscis and a
ciliated channel conducts the food to the trunk.
Perhaps the most remarkable feeding adaptations among the spoon worms can be seen in
Urechis. U. caupo lives in a large, U-shaped burrow and by pulsating its body it drives water
through its lair. To feed, it produces a conical mucus net that lines the burrow as water is
sucked in at a rate of about 18L per hour. Edible particles are caught on the net, and after
some time the worm slowly eats the net and all the edible matter sticking to it.
Reproduction
Echiurans have separate male and female individuals. The gonads are associated with the
membrane lining the body cavity, into which they release the gametes. The sperm and eggs
complete their maturation in the body cavity, before being released into the surrounding
water. Fertilisation is external.