Dodecolopoda

Dodecolopoda is a monotypic genus of sea spider (class Pycnogonida) in the family Colossendeidae. The only species in this genus is Dodecolopoda mawsoni, first described by William Thomas Calman and Isabella Gordon in 1933 based on a male holotype found off the coast of MacRobertson Land. Calman and Gordon named this species for Sir Douglas Mawson, who obtained this specimen on his voyage to the Antarctic region in 1931.

Description
This species is notable as one of only two species of sea spider with six pairs of legs (instead of the usual four leg pairs) and the first such species to be discovered. This sea spider is also notable for its gigantic size, measuring 20 in from tip to tip of its legs when fully extended. The leg of the fourth pair on the holotype, for example, measures 240.3 mm in length. The sea spider's long legs act as stilts, holding its body well above the seabed surface below.

These sea spiders resemble the ten-legged species in the genus Decolopoda but feature a longer proboscis compared to the trunk, a longer tarsus and shorter claw compared to the propodus, and setose legs, as well as more legs and a much larger size. Both of these polymerous (i.e., extra-legged) genera resemble the eight-legged species in the genus Colossendeis (e.g., C. wilsoni) but retain chelifores as adults. Phylogenetic analysis indicates that both Dodecolopoda and Decolopoda are nested within the genus Colossendeis in a phylogenetic tree, so that Colossendeis is paraphyletic with respect to these two polymerous genera.

Distribution
This species is found in the Indian and Atlantic regions of the Southern Ocean and is endemic to the Antarctic region.