Identification
They have a cephalothorax and a smaller abdomen.
Four to six pairs of legs for walking. Some have additional leg-like appendages.
Life Cycle
Separate sexes, except for one hermaphroditic species.
Remarks
They are not spiders, despite their common name (Sea spiders).
Internet References
EoL. Pantopoda (Sea spiders)
Wikicommons. External anatomy of
Nymphon sea spider.