kids encyclopedia robot

Sea spider facts for kids

Kids Encyclopedia Facts
Quick facts for kids
Sea spiders
Temporal range: late Cambrian – Present
Sea spider.jpg
Scientific classification
Kingdom:
Phylum:
Subphylum:
Class:
Pycnogonida
Pycnogonid
A sea spider in its natural home

Sea spiders are amazing marine animals. They belong to a group called arthropods, just like insects and crabs. Their scientific class is Pycnogonida.

There are about 1,300 different kinds, or species, of sea spiders. You can find them all over the world, in every ocean. This includes places like the Mediterranean Sea, the Caribbean Sea, and even the super cold Arctic Ocean.

Sea spiders living near the coast are usually small. They might have legs that spread out about 1 inch (2.5 cm). But those living deep in the ocean can be much bigger! Their leg span can reach up to 24 inches (60 cm).

It's important to know that sea spiders are not "true" spiders. They are also not arachnids, which is the group that includes spiders and scorpions. Scientists used to think they were closely related to true spiders. However, new studies of their genes suggest they might be a very old group of animals. They could be a "sister group" to all other living arthropods. This means they branched off very early in the history of life.

What Sea Spiders Look Like

Nymphon-leptocheles
A sea spider eating a hydroid

A sea spider has a small, thin body. It usually has four pairs of long, skinny legs. These legs are attached to its main body, which is like an abdomen.

On its head, a sea spider usually has three other pairs of special parts:

  • Chelicerae: These are like tiny claws. Sea spiders use them to grab their food.
  • Palps: These are sensory feelers. They help the sea spider explore its surroundings.
  • Egg-carrying legs: These are special legs used for carrying eggs. In some female sea spiders, these legs might be small or missing.

When a female sea spider lays eggs, she puts them in round groups on the male's egg-carrying legs. The male then carries these eggs until they hatch.

How Sea Spiders Eat

On top of a sea spider's head, there is a bumpy part with simple eyes. It can have two, three, or four eyes. The front of its head has a long snout with a mouth that sucks.

Sea spiders are like tiny vampires of the sea! They feed by sucking the body juices from other marine animals. Their favorite meals include sea anemones, sponges, and sea squirts.

Images for kids

See also

Kids robot.svg In Spanish: Picnogónidos para niños

kids search engine
Sea spider Facts for Kids. Kiddle Encyclopedia.