Decolopoda | |
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Illustration of D. australis, from a specimen found at the South Shetlands by the Scottia Expedition. | |
Scientific classification
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Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Subphylum: | Chelicerata |
Class: | Pycnogonida |
Order: | Pantopoda |
Family: | Colossendeidae |
Genus: |
Decolopoda Eights, 1835 |
Decolopoda is a genus of sea spider ( class Pycnogonida) belonging to the family Colossendeidae. [1] This genus includes two valid species, D. australis and D. qasimi. [1] As the name of this genus implies, these two species are among the seven species of sea spider with five pairs of legs instead of the usual four leg pairs. [2]
The species D. australis is notable as the first polymerous (i.e., extra-legged) sea spider to be discovered and was first described by James Eights based on specimens found off the South Shetland Islands in the Antarctic region in 1834. [3] [4] [5] Naturalists mostly ignored his discovery, dismissing the description by Eights as erroneous or based on a monstrosity, until the discovery of more ten-legged species several decades later. [4] [5] Authorities have since deemed one of these species, D. antarctica, which was described in 1905, to be a junior synonym of D. australis, [1] but another species in this genus, D. qasimi, was described in 1993, based on a male holotype found off the coast of Queen Maud Land in Antarctica, and named for the Indian marine biologist Syed Zahoor Qasim. [4]
The sea spiders in this genus resemble those found in the genus Colossendeis (e.g., C. wilsoni) but are larger and retain chelifores in adults. [5] [4] Sea spiders of the giant species D. australis are bright scarlet, [3] they often weigh more than 10 g, and their legs span more than 20 cm. [6] The holotype for the species D. qasimi is dark maroon (when preserved) and has even longer legs (184.7 mm in length, compared to 100 mm for D. australis). [4] The species D. qasimi also differs from other species by having denticulate spines on its ovigers and hair only on its legs. [4] Phylogenetic studies indicate that the genus Decolopoda is nested within the genus Colossendeis in a phylogenetic tree, so that Colossendeis is paraphyletic with respect to Decolopoda. [7] [8]
Both species in this genus are found in the Southern Ocean and are endemic to the Antarctic region. [9]
Decolopoda | |
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![]() | |
Illustration of D. australis, from a specimen found at the South Shetlands by the Scottia Expedition. | |
Scientific classification
![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Subphylum: | Chelicerata |
Class: | Pycnogonida |
Order: | Pantopoda |
Family: | Colossendeidae |
Genus: |
Decolopoda Eights, 1835 |
Decolopoda is a genus of sea spider ( class Pycnogonida) belonging to the family Colossendeidae. [1] This genus includes two valid species, D. australis and D. qasimi. [1] As the name of this genus implies, these two species are among the seven species of sea spider with five pairs of legs instead of the usual four leg pairs. [2]
The species D. australis is notable as the first polymerous (i.e., extra-legged) sea spider to be discovered and was first described by James Eights based on specimens found off the South Shetland Islands in the Antarctic region in 1834. [3] [4] [5] Naturalists mostly ignored his discovery, dismissing the description by Eights as erroneous or based on a monstrosity, until the discovery of more ten-legged species several decades later. [4] [5] Authorities have since deemed one of these species, D. antarctica, which was described in 1905, to be a junior synonym of D. australis, [1] but another species in this genus, D. qasimi, was described in 1993, based on a male holotype found off the coast of Queen Maud Land in Antarctica, and named for the Indian marine biologist Syed Zahoor Qasim. [4]
The sea spiders in this genus resemble those found in the genus Colossendeis (e.g., C. wilsoni) but are larger and retain chelifores in adults. [5] [4] Sea spiders of the giant species D. australis are bright scarlet, [3] they often weigh more than 10 g, and their legs span more than 20 cm. [6] The holotype for the species D. qasimi is dark maroon (when preserved) and has even longer legs (184.7 mm in length, compared to 100 mm for D. australis). [4] The species D. qasimi also differs from other species by having denticulate spines on its ovigers and hair only on its legs. [4] Phylogenetic studies indicate that the genus Decolopoda is nested within the genus Colossendeis in a phylogenetic tree, so that Colossendeis is paraphyletic with respect to Decolopoda. [7] [8]
Both species in this genus are found in the Southern Ocean and are endemic to the Antarctic region. [9]