photo credit Jayson Gillespie
Sea spiders are classified in the phylum
Arthropoda and the class Pycnogonida. Pycnogonids are spider-like
in their appearance and hence the name "sea spider".
They are quite common in the marine environment but you need
a keen and careful eye to spot them. Most sea spiders are 1 to
10 mm in length but some deepwater species
in Antarctica can have a leg span up to 90cm! Sea spiders are
found throughout the worlds oceans, in a variety of habitats,
ranging from the intertidal to the subtidal. You can find some
sea spiders on rocks and dock pilings around hydroids and bryozoans.
Many sea spiders are carnivores and feed on hydroids, soft corals,
anemones, bryozoans, small polychaetes, and sponges, but some
species will also eat algae.
and Answers about Marine Arthropods
to Marine Biodiversity index