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198

giant sea spider

OLogy Series
animal
card
198

giant sea spider

OLogy Series
animal

Some exotic creatures lurk in the polar seas, but perhaps none is more bizarre than the giant sea spider. There are hundreds of sea spiders in oceans around the world, but the giant sea spider weighs about 1,000 times more than its relatives. Its legs can span up to two feet across, but its body usually measures just a couple inches long.

To get around, sea spiders often drift with the currents, or cling to moving animals. They can also:

fly

walk

both A and B

Are you right?

Correct!

In addition to drifting or hitching a ride on another animal, sea spiders have been observed to walk along the ocean floor.

Like many other animals, sea spiders grow much larger in:

warmer seas

colder seas

hot springs

Are you right?

Correct!

Many animals besides sea spiders grow to much larger sizes in colder oceans. The reason species in polar waters reach such enormous sizes is because there are higher levels of oxygen in colder waters.

The sea spiders' organs for respiration (breathing) and digestion are located in its enormously long legs.

Fact
or
Fiction
?

Fact

Parts of the giant sea spider's respiratory and digestive systems are found in its legs.

Sea spiders always have eight legs, as their name implies.

Fact
or
Fiction
?

Fiction

Sea spiders are actually born with six legs, but soon develop another pair. In some cases, sea spiders have been known to grow more than eight legs.

giant sea spider
Scientific name: Colossendes megalonyx
Size: a tiny body but long legs that extend more than two feet across
Habitat: the deep sea and the polar oceans
Diet: suck the juices from soft-bodied invertebrates like clams
Characteristics: eight long legs, orange body, complex eye, a proboscis (a long, tubular mouth)

Image credits: courtesy of AMNH, Norbert Wu.