Sea spiders are a class of marine arthropods called Pycnogonida that are found nearly everywhere in oceans from deep to shallow ranges. They are not arachnids, but considered chelicerates even though this fact may be debated. They feed on ocean invertebrates using a proboscis and suction feeding.
Sea spiders use external fertilization and interestingly the male provides care to the young.
Watch the sea spider video below!
To learn more check out this 2009 article in Science Magazine complete with a slideshow of deep sea spiders feeding!