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What the sources say

Giant Antarctic Sea SpiderColossendeis megalonyx

Every figure, record and mechanism on the Giant Antarctic Sea Spider profile was written from a source, and this is the working table behind it: 45 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

Dietz et al. 2015

Dietz et al. (2015). Regional differentiation and extensive hybridization between mitochondrial clades of the Southern Ocean giant sea spider Colossendeis megalonyx. Royal Society Open Science.

The page saysA giant sea spider of the Southern Ocean
The source saysthe circumpolar giant sea spider Colossendeis megalonyx
The page saysSouthern Ocean, with a circumpolar distribution in Antarctic and Subantarctic waters, from 3 to 4900 m deep
The source sayswith a circumpolar distribution in Antarctic and Subantarctic waters and also found in South America, South Africa and Madagascar, from 3 to 4900 m depth
The page saysThis spider is found around Antarctica and in Subantarctic waters, and is also found in South America, South Africa and Madagascar, at depths from 3 to 4900 m.
The source sayswith a circumpolar distribution in Antarctic and Subantarctic waters and also found in South America, South Africa and Madagascar, from 3 to 4900 m depth
The page saysA DNA study of over 500 specimens found 15 to 20 distinct groups in its mitochondrial DNA
The source sayswe expand the sampling to include over 500 mitochondrial COI sequences of specimens from around the Antarctic. Using multiple species delimitation approaches, the number of distinct mitochondrial OTUs increased from six to 15–20Note: OTUs rendered as groups in its mitochondrial DNA.
The page saysYet nuclear DNA results from some of those specimens suggested that several of those lineages can hybridize and should not be read as separate species.
The source saysanalysis of the nuclear internal transcribed spacer region for a subset of these specimens showed incongruence between nuclear and mitochondrial results. These mito-nuclear discordances suggest that several of the divergent mitochondrial lineages can hybridize and should not be interpreted as cryptic species.
The page saysA 2015 study with more samples counted 15 to 20 mitochondrial groups, but its nuclear DNA results suggested that several of them interbreed and should not be treated as hidden species.
The source sayswe expand the sampling to include over 500 mitochondrial COI sequences of specimens from around the Antarctic. Using multiple species delimitation approaches, the number of distinct mitochondrial OTUs increased from six to 15–20 ... These mito-nuclear discordances suggest that several of the divergent mitochondrial lineages can hybridize and should not be interpreted as cryptic species.Note: 2015 is the reference year. OTUs rendered as mitochondrial groups; 'can hybridize' as interbreed; 'cryptic' as hidden.
The page saysEarlier mitochondrial DNA work suggested it was a complex of at least six hidden species.
The source saysBased on mitochondrial markers, it was recently suggested that the circumpolar giant sea spider Colossendeis megalonyx comprises a complex of at least six cryptic species
The page saysNot Evaluated
The source saysthe circumpolar giant sea spider Colossendeis megalonyxNote: stats.conservationStatus. Anchors the species name only; the body makes no status claim. GBIF's copy of the IUCN Red List returns category NOT_EVALUATED for Colossendeis megalonyx Hoek, 1881 (api.gbif.org/v1/species/2117581/iucnRedListCategory, fetched 2026-10-11); an API endpoint can't be cited, and no page found states it, so no IUCN reference is cited (#1227).

Source
02

Moran, Lobert & Toh 2024

Moran, Lobert & Toh (2024). Spawning and larval development of Colossendeis megalonyx, a giant Antarctic sea spider. Ecology.

The page saysIts family, the Colossendeidae, includes the largest and most conspicuous of the sea spiders, with some species reaching leg spans of 40-50 cm.
The source saysColossendeids include the largest and most ... conspicuous of sea spiders, with some species reaching leg spans of 40-50 cmNote: Family scope (Colossendeidae), not stated for C. megalonyx.
The page saysAround McMurdo Sound in Antarctica, colossendeids are abundant at scuba depths.
The source saysMcMurdo Sound, Antarctica, where colossendeids are ... abundant at SCUBA depths
The page saysDivers there frequently saw stacks of usually two, sometimes three or four, colossendeids on top of each other, a mating posture in other sea spiders.
The source saysMcMurdo Sound, Antarctica, where colossendeids are ... abundant at SCUBA depths, divers had frequently observed groups of usually two, but ... sometimes three or four individuals stacked on top of each other ... in what is characteristically a mating posture in other sea spiders
The page saysResearchers collected several mating groups of C. megalonyx and kept them at between -1.5 and -0.5 °C, and two groups laid eggs in the lab.
The source sayswe hand-collected several mating groups of C. megalonyx , transported ... them to McMurdo Station, kept them in a flow-through seawater system at temperatures between ... -1.5 and -0.5 ... Two of these mating ... groups produced eggs in the laboratory in 2021
The page saysThe first mass held thousands of eggs, averaging about 107 micrometres across.
The source saysThe first mass contained ... thousands (though we did not count them) of light-colored, small eggs (average diameter 106.9Note: 106.9 micrometres average diameter, rounded to 107; the quote stops before the unit because the PDF text drops the mu sign.
The page saysMost other groups of sea spiders brood their eggs on the father's ovigerous legs
The source saysthe paternal brooding exhibited by most other ... groups of sea spidersNote: Also: males who brood embryos on specialized ovigerous legs (same manuscript).
The page saysbrooding has never been observed in the family Colossendeidae
The source saysbrooding has never been observed in three of the eleven recognized extant families of ... pycnogonids, including the family Colossendeidae
The page saysOne adult stayed on or close to the egg mass for almost three days, appearing to groom it, and in that time the mass became firmly attached to the rock.
The source saysOne adult from the mating group remained on or close ... to the egg mass for almost three days after the eggs were produced, appearing to groom and ... manipulate the mass ... During this ... grooming period the mass became compacted and firmly attached to the rock.
The page saysThe authors think that adult was male, and potentially the father.
The source saysWe think the adult ... that tended the mass was male, and potentially the father
The page saysDevelopment was slow.
The source saysDevelopment was slow, as is characteristic of ... Antarctic ectotherms
The page saysThe first larva hatched about eight months after the eggs were laid
The source saysThe first hatched larva was observed on June 28, ... 2022, ~ eight months post-spawnNote: "after" paraphrases "post-spawn".
The page saysthe hatched larvae were negatively buoyant, meaning they sank, and crawled slowly in the dish.
The source saysHatched larvae were negatively buoyant and crawled slowly in the dish.
The page saysIn a lab study with eggs held at -1.8 °C, the first larva appeared about eight months after spawning, and larvae were still hatching in October 2022, when the researchers stopped watching.
The source saysWe maintained the embryos ... in filtered seawater in incubators at -1.8 °C for ... months ... The first hatched larva was observed on June 28, ... 2022, ~ eight months post-spawn; a major hatching event occurred on July 25; and hatching ... continued through October 2022 when the observations were discontinuedNote: "after spawning" paraphrases "post-spawn".
The page saysIts eggs, held at -1.8 °C in the lab, took about eight months to give a first larva
The source saysWe maintained the embryos ... in filtered seawater in incubators at -1.8 °C for ... months ... The first hatched larva was observed on June 28, ... 2022, ~ eight months post-spawn; a major hatching event occurred on July 25; and hatching ... continued through October 2022 when the observations were discontinuedNote: vibe.reason, same quote as the body

Source
03

Moran et al. 2018

Moran et al. (2018). Predatory behavior of giant Antarctic sea spiders (Colossendeis) in nearshore environments. Invertebrate Biology.

The page saysfeeds on open-water animals
The source saysColossendeis megalonyx , fed on a variety of pelagic organisms, particularly the pteropod Clione antarctica
The page saysPelagic (open-water) animals, particularly the pteropod Clione antarctica
The source saysfed on a variety of pelagic organisms, particularly the pteropod Clione antarctica
The page saysResearchers diving there recorded C. megalonyx feeding on pelagic organisms
The source saysWe documented two species feeding on a variety of benthic and pelagic invertebrates during three diving field seasons at McMurdo Station, Antarctica. Individuals of one species, Colossendeis megalonyx , fed on a variety of pelagic organisms
The page saysIt fed particularly on the pteropod Clione antarctica.
The source saysparticularly the pteropod Clione antarctica
The page saysVideo of captive spiders showed them capturing C. antarctica rapidly.
The source saysWe used video to document rapid capture of individuals of C. antarctica by captive specimens of C. megalonyx in the laboratory
The page saysThe researchers suggest that, at least near the shore, pelagic invertebrates are an important food source for this species.
The source sayswe suggest that, at least in the nearshore environment, pelagic invertebrates are an important food source for this and potentially other pycnogonid species
The page saysOver three diving seasons at McMurdo Station, Antarctica, researchers watched it eat a variety of open-water (pelagic) animals, especially the pteropod Clione antarctica.
The source saysWe documented two species feeding on a variety of benthic and pelagic invertebrates during three diving field seasons at McMurdo Station, Antarctica. Individuals of one species, Colossendeis megalonyx , fed on a variety of pelagic organisms, particularly the pteropod Clione antarcticaNote: 'especially' renders 'particularly'.
The page saysIn the lab they filmed captive spiders seizing that pteropod quickly.
The source saysWe used video to document rapid capture of individuals of C. antarctica by captive specimens of C. megalonyx in the laboratory

Source
04

Shishido et al. 2019

Shishido et al. (2019). Polar gigantism and the oxygen–temperature hypothesis: a test of upper thermal limits to body size in Antarctic pycnogonids. Proceedings of the Royal Society B: Biological Sciences.

The page saysIn one study, the bigger the animal, the more porous its cuticle, especially in Colossendeis megalonyx.
The source saysas body size increases, porosity increases as well, especially in C. megalonyx
The page saysThe authors suggest that may help a larger body get enough oxygen.
The source sayswhich may compensate for the increasing metabolic demand and longer diffusion distances of larger animals by facilitating diffusive oxygen supply
The page saysIn tests from -1.8 °C up to 9 °C, giant Antarctic sea spiders from two genera, including Colossendeis, were highly sensitive to elevated temperature
The source saystwo genera of giant Antarctic sea spiders (Pycnogonida), Colossendeis and Ammothea ... We tested performance at four temperatures spanning ambient (-1.8°C) to 9°C. Individuals from both genera were highly sensitive to elevated temperature
The page saysC. megalonyx kept performing at considerably higher temperatures than another giant, Ammothea glacialis.
The source saysC. megalonyx maintained performance at considerably higher temperatures
The page saysA 2019 study found that bigger animals had more porous cuticles, especially in Colossendeis megalonyx
The source saysas body size increases, porosity increases as well, especially in C. megalonyxNote: 2019 is the reference year.
The page saysWarm water is a problem.
The source saysIndividuals from both genera were highly sensitive to elevated temperatureNote: Paraphrase of the next claim's source line, for the short sentence.
The page saysthe authors suggest this may help a larger body take in enough oxygen
The source sayswhich may compensate for the increasing metabolic demand and longer diffusion distances of larger animals by facilitating diffusive oxygen supply

Source
05

Lane et al. 2018

Lane et al. (2018). Cuticular gas exchange by Antarctic sea spiders. Journal of Experimental Biology.

The page sayslike all sea spiders, has no gills
The source saysmarine arthropods that lack gills and rely on cutaneous respirationNote: Lane's abstract states it of the group: 'Pycnogonids, or sea spiders, are marine arthropods that lack gills'. Sea-spider scope, worded as such.
The page saysLike other sea spiders it has no gills: oxygen diffuses in through pores in its cuticle
The source sayslack gills and rely on cutaneous respiration ... the pores facilitate oxygen diffusionNote: Sea-spider scope.
The page saysSea spiders have no gills.
The source saysmarine arthropods that lack gills and rely on cutaneous respiration
The page saysThey breathe through the cuticle, the outer layer of the body, which contains pores.
The source saysrely on cutaneous respiration ... Their cuticle contains pores
The page saysOne study modelled the oxygen flowing in through all those pores and found it closely matched what the animals use, which means the pores help oxygen diffuse in.
The source saysmodeling diffusive oxygen fluxes across all pores in the body of sea spiders ... Modeled oxygen fluxes through pores closely matched oxygen consumption across a range of body sizes, which means the pores facilitate oxygen diffusion.

Source
06

Woods et al. 2017

Woods et al. (2017). Respiratory gut peristalsis by sea spiders. Current Biology.

The page saysContractions of the gut's many side branches drive flows of gut fluid and hemolymph
The source saysflows of gut fluids and hemolymph driven by peristaltic contractions of a space-filling system of gut diverticula
The page saysThat study called it a previously undescribed way of moving oxygen inside the body.
The source saysuse a previously undescribed mechanism of internal O 2 transport
The page saysSea spiders also use their guts as pumps.
The source saysdriven by peristaltic contractions of a space-filling system of gut diverticula

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.