Pentanymphon

Pentanymphon is a monotypic genus of sea spider (class Pycnogonida) in the family Nymphonidae. The only species in this genus is Pentanymphon antarcticum. As the name of this genus suggests, this genus is among the four genera of sea spiders with five pairs of legs in adults instead of the usual four leg pairs. The species P. antarcticum was the second polymerous (i.e., extra-legged) sea spider to be discovered.

== Discovery and taxonomy == This genus and its only species were first described in 1904 by the British biologist Thomas V. Hodgson. He based the original description of this sea spider on 28 specimens including both sexes collected during the British National Antarctic Expedition. The Royal Research Ship Discovery collected these specimens in Winter Quarters Bay in McMurdo Sound from depths ranging from 12 to 125 fathoms. Hodgson named this genus to indicate that this species would be placed in the genus Nymphon but for the presence of a fifth pair of legs.