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What the sources say

Atlantic HagfishMyxine glutinosa

Every figure, record and mechanism on the Atlantic Hagfish profile was written from a source, and this is the working table behind it: 50 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

FishBase

Myxine glutinosa (Linnaeus, 1758), Atlantic hagfish. FishBase.

The page saysDead and dying fish, bored into for the viscera and musculature
The source saysFeeds chiefly on dead and dying fish of varying species by boring into the body and consuming viscera and musculature.
The page saysMuddy North Atlantic sea floors at 2 to 13°C (depths of 20 to 1,200 meters, usually 27 to 460)
The source saysdepth range 20 - 1200 m [...] usually 27 - 460 m [...] Boreal; 2°C - 13°C [...] North Atlantic: Murmansk to the Mediterranean Sea; Greenland to USA. [...] Found on muddy bottoms where they hide in the mud.
The page saysdangerLevel: Low
The source saysThreat to humans Harmless
The page saysa jawless mouth, a single nostril, one pair of gill openings
The source saysJawless mouth, single nasal aperture, only a single pair of external gill openings, no operculum or covering fold of skin.Note: "nostril" for the source's "nasal aperture", explained for an 11 to 14 year-old reader; same structure, no change of scope.
The page saysA big adult reaches 95 centimeters, though a common length is 30 centimeters, or 40 for a female
The source saysMax length : 95.0 cm TL male/unsexed [...] common length : 30.0 cm TL male/unsexed [...] common length :40 cm TL (female)
The page saysOf the Atlantic hagfish, FishBase says that its slime is used for defense.
The source saysSlime is used for defense.
The page saysAtlantic hagfish range the North Atlantic, Greenland and the USA to Murmansk and down to the Mediterranean Sea (absent from its eastern end and the Black Sea), in 2 to 13°C water from 20 to 1,200 meters down.
The source saysdepth range 20 - 1200 m [...] Boreal; 2°C - 13°C [...] North Atlantic: Murmansk to the Mediterranean Sea; Greenland to USA. Absent in eastern Mediterranean and Black Sea.
The page saysIt is the only hagfish in the northeast Atlantic.
The source saysOnly hagfish in the Northeast Atlantic.
The page saysThey hide in muddy bottoms
The source saysFound on muddy bottoms where they hide in the mud.
The page saysand are chiefly nocturnal
The source saysChiefly nocturnal.
The page saysThe diet is chiefly dead and dying fish, bored into for viscera and musculature
The source saysFeeds chiefly on dead and dying fish of varying species by boring into the body and consuming viscera and musculature.

Source
02

Martini, Heiser & Lesser 1997

Martini, Heiser & Lesser (1997). A population profile for Atlantic hagfish, Myxine glutinosa (L.), in the Gulf of Maine. Part I: Morphometrics and reproductive state. Fishery Bulletin (NOAA Fisheries).

The page saysjuveniles may feed solely on invertebrates in the substrate
The source saysJuveniles may, for example, feed solely on invertebrates within the substrate.
The page saysbarbels. Hagfish
The source sayswith nose and barbels exposed to passing currentsNote: claims the barbels only; the sentence lists them without describing their arrangement
The page saysBehind the mouth there is no jaw, and the feeding apparatus is tooth cusp plates and a dental muscle complex.
The source saysThe feeding apparatus, consisting of the tooth cusp plates and the dental muscle complexNote: jawlessness is FishBase's "Jawless mouth" on the same species page
The page saysOne Gulf of Maine sample averaged 51 centimeters (19.5 to 72.4)
The source saysTotal length (mm) 509 104 195-724Note: table row: mean 509 mm, SD 104, range 195-724 mm, n=202; converted to centimetres so the page keeps one unit throughout (509 mm = 50.9, rounded to 51; 195 mm = 19.5; 724 mm = 72.4).
The page saysthose over 35 centimeters had an average weight of 140 grams
The source saysthe average weight for Gulf of Maine specimens greater than 350 mm was 140 gNote: 350 mm = 35 cm; converted so the page keeps one unit throughout.
The page saysA Gulf of Maine survey counted 114 slime pores on average down the left side alone.
The source saysTotal slime pores (left side) 114 7 91-128Note: table row: mean 114 pores, SD 7, range 91-128, n=94
The page saysusually in shallow burrows with nose and barbels in the current
The source saysIndividual hagfish are usually found in shallow, sinusoidal, temporary burrows, with nose and barbels exposed to passing currents.
The page saysjuveniles may feed solely on invertebrates in the substrate.
The source saysJuveniles may, for example, feed solely on invertebrates within the substrate.
The page saysHow long one lives is not known: the Gulf of Maine population profile reports no data on life span or growth rates.
The source saysNo data are available concerning the life span or growth rates for this species.
The page saysweightKg: 0.14
The source saysthe average weight for Gulf of Maine specimens greater than 350 mm was 140 gNote: task #592; 140 g = 0.14 kg, the average for the fishable size class in the Gulf of Maine population profile, and the only whole-animal average on record for the species. Light class (0.1 to 10 kg), where the name guess gave Medium. Not in a curated matchup

Source
03

Winegard & Fudge 2010

Winegard & Fudge (2010). Deployment of hagfish slime thread skeins requires the transmission of mixing forces via mucin strands. Journal of Experimental Biology.

The page saysunravel a coiled fiber bundle into a thread a hundred times longer in a fraction of a second
The source saysDeployment of the thread skeins involves their unraveling in a fraction of a second from a 150 microm-long ellipsoid bundle to a thread that is 100x longerNote: Winegard & Fudge 2010 is the Atlantic hagfish study: Fudge & Schorno 2016 attributes it to Myxine glutinosa as reference 25
The page saysMucus vesicles mixed into seawater swell into long strands that attach to a thread bundle and transmit the forces that unravel it, turning a 150-micrometer coil into a thread a hundred times longer in a fraction of a second.
The source saysDeployment of the thread skeins involves their unraveling in a fraction of a second from a 150 microm-long ellipsoid bundle to a thread that is 100x longer [...] mucin vesicles mixed into seawater swell and elongate into high-aspect ratio mucin strands that attach to the thread skeins, transmit hydrodynamic forces to them
The page saysMixed into seawater the mucus vesicles swell into long strands that attach to a fiber bundle and transmit the mixing forces into it, unraveling a coil barely 150 micrometers long into a thread a hundred times longer in a fraction of a second. Both the mixing and the mucus are required.
The source saysDeployment of the thread skeins involves their unraveling in a fraction of a second from a 150 microm-long ellipsoid bundle to a thread that is 100x longer [...] mixing and mucin vesicles are indeed crucial for skein unraveling [...] mucin vesicles mixed into seawater swell and elongate into high-aspect ratio mucin strands that attach to the thread skeins, transmit hydrodynamic forces to them
The page saysEach slime gland releases two things at once: tightly coiled bundles of protein fiber and vesicles of mucus.
The source saysThe slime originates as a two-component glandular exudate comprised of coiled bundles of cytoskeletal intermediate filaments (thread skeins) and mucin vesicles.

Source
04

Schorno, Gillis & Fudge 2018

Schorno, Gillis & Fudge (2018). Emptying and refilling of slime glands in Atlantic ( Myxine glutinosa ) and Pacific ( Eptatretus stoutii ) hagfishes. Journal of Experimental Biology.

The page saysEmptied glands take three to four weeks to refill in both, though the Pacific hagfish recovers exudate at the faster absolute rate.
The source saysComplete refilling of slime glands for both species took 3-4 weeks, with Pacific hagfish achieving faster absolute rates of exudate recovery than Atlantic hagfish.
The page saysCompletely refilling emptied slime glands takes three to four weeks in both Atlantic and Pacific hagfish, though lab comparisons found Pacific hagfish recover their exudate faster than their Atlantic relatives do.
The source saysComplete refilling of slime glands for both species took 3-4 weeks, with Pacific hagfish achieving faster absolute rates of exudate recovery than Atlantic hagfish.

Source
05

Zintzen et al. 2011

Zintzen et al. (2011). Hagfish predatory behaviour and slime defence mechanism. Scientific Reports.

The page saysA 2011 study put baited video units on the seafloor off New Zealand, 50 to 1,200 meters down.
The source saysAt each location, videos were deployed during daylight hours at a series of depths from 50 to ~1,200 m, yielding a total of 165 deployments.Note: locations are off New Zealand (White Island, Great Barrier Island, Three Kings Islands); 2011 is the reference's publication year from Crossref, not restated in the body text
The page saysThe hagfish on those tapes were New Zealand species, not Atlantic hagfish.
The source saysIn each case, the hagfish species under attack are denoted with numbers in brackets as follows: (1) Eptatretus cirrhatus (Forster in Bloch & Schneider, 1801), (2) Eptatretus sp.2 and (3) Neomyxine sp.1.
The page saysslime filled the mouth and gill chamber in under four-tenths of a second, the predators convulsed their gill arches in a gagging effort to clear it
The source saysslime secreted by hagfishes fills the mouth and gill chamber of their predators, acting as a very rapid (<0.4 sec) and effective defence mechanism [...] The predators convulsed their gill arches dramatically in a gagging-type effort to clear the slime from their gill chambers.
The page saysIn 14 recorded incidents, catsharks, spiny dogfish and conger eels were clearly repelled
The source sayswe observed 14 separate incidents where predators were clearly repelled by hagfish slime [...] Scyliorhinidae – Catsharks [...] Squalidae – Spiny dogfishes [...] Congridae – Conger eels
The page saysand could not acquire their prey
The source saysBiters (sharks, conger eels) and suckers (wreckfishes, scorpionfishes) could not successfully acquire their potential hagfish prey.
The page saysThe hagfish, in all cases, appeared to sustain no injury, often carrying on feeding.
The source saysThe hagfishes, in all cases, appeared to sustain no injury, often continuing to feed on the bait
The page saysit comes from New Zealand hagfish species, not the Atlantic hagfish
The source saysIn each case, the hagfish species under attack are denoted with numbers in brackets as follows: (1) Eptatretus cirrhatus (Forster in Bloch & Schneider, 1801), (2) Eptatretus sp.2 and (3) Neomyxine sp.1.
The page saysA 2011 baited-camera study found catsharks, spiny dogfish and conger eels
The source saysList of predatory fish species, recorded and observed in video footage, whose gills were clogged by hagfish slime. [...] Scyliorhinidae – Catsharks [...] Squalidae – Spiny dogfishes [...] Congridae – Conger eelsNote: 2011 is the reference's publication year from Crossref, not restated in the paper's body text
The page sayscould not successfully acquire their hagfish prey
The source saysBiters (sharks, conger eels) and suckers (wreckfishes, scorpionfishes) could not successfully acquire their potential hagfish prey.
The page saysslime filled the mouth and gill chamber in under four-tenths of a second, and the predators convulsed their gill arches in a gagging effort to clear it.
The source saysslime secreted by hagfishes fills the mouth and gill chamber of their predators, acting as a very rapid (<0.4 sec) and effective defence mechanism [...] The predators convulsed their gill arches dramatically in a gagging-type effort to clear the slime from their gill chambers.

Source
06

Fudge & Schorno 2016

Fudge & Schorno (2016). The Hagfish Gland Thread Cell: A Fiber-Producing Cell Involved in Predator Defense. Cells.

The page saysDefensive slime that unravels into gill-clogging protein thread in a fraction of a second
The source saysOne of the primary functions of hagfish slime is to deter fish predators by clogging their gills [...] the coiled thread (or skein) they produce unravels in a fraction of a second after being ejected from the slime glandNote: gill-clogging is stated for hagfish slime as a group; FishBase states at species level that the Atlantic hagfish's "Slime is used for defense"
The page saysProvoke it and striated muscle squeezes the slime gland, firing coiled protein thread that unravels in a fraction of a second.
The source saysWhen provoked, the striated muscle around the gland (M) contracts, forcing the two cell types out through the gland pore (P) into the surrounding seawater, where they form into whole slime within a fraction of a second
The page saysEach gland behind them holds thread cells packed with coiled bundles of protein fiber, and mucus cells; striated muscle squeezes both into the seawater when the animal is provoked.
The source saysHagfish slime glands, which are continuous with the skin (S), produce two main slime secretory cell types, the gland thread cells (GTCs) and gland mucus cells (GMCs). When provoked, the striated muscle around the gland (M) contracts, forcing the two cell types out through the gland pore (P) into the surrounding seawaterNote: "coiled bundles of protein fiber" is winegard-fudge-2010's "coiled bundles of cytoskeletal intermediate filaments (thread skeins)"
The page saysClogging the gills of fish predators is one of the primary functions of hagfish slime, and the threads keep a predator from flushing it out.
The source saysOne of the primary functions of hagfish slime is to deter fish predators by clogging their gills [...] The threads lend mechanical coherence to the slime, and also help prevent the predator from being able to flush the slime off via vigorous movements of the gill opercula.
The page saysAtlantic hagfish skeins need both vigorous mixing and mucus to unravel, while Pacific hagfish skeins come undone spontaneously
The source saysIn the Atlantic hagfish, Myxine glutinosa , unravelling is driven by external forces acting on the skein. Specifically, vigorous mixing and the presence of mucus are both required for unraveling to proceed [...] In contrast, skeins from the Pacific hagfish, Eptatretus stoutii , do not require vigorous mixing or the presence of mucus; unraveling proceeds spontaneously

Source
07

Bradshaw & Allison 2022

Bradshaw & Allison (2022). Hagfish to Illuminate the Developmental and Evolutionary Origins of the Vertebrate Retina. Frontiers in Cell and Developmental Biology.

The page saysHagfish and lampreys are the most ancient extant vertebrates
The source saysthe most ancient extant vertebrates, the hagfish and lamprey
The page saysthe hagfish eye is strikingly rudimentary: no lens, no pigment
The source sayshagfish eyes are strikingly rudimentary [...] Hagfish eyes also lack a lens and pigment (features found in the eyes of all other living vertebrates)
The page saysin the genus *Myxine* buried under a layer of muscle
The source saysTheir diminutive eyes are covered by a layer of semi-transparent skin (Genus Eptatretus ) or a layer of muscle (Genus Myxine )
The page sayspossibly a photoreceptive organ for circadian timing rather than image formation
The source saysthe hagfish eye may represent a more ancestral photoreceptive organ for circadian entrainment rather than image formation

Source
08

Subramanian, Ross & MacKinnon 2009

Subramanian, Ross & MacKinnon (2009). Myxinidin, A Novel Antimicrobial Peptide from the Epidermal Mucus of Hagfish, Myxine glutinosa L. Marine Biotechnology.

The page saysmyxinidin, a 12-amino-acid peptide from this species' mucus, killed a broad range of bacteria and yeast pathogens, two to 16 times more effectively than the potent fish peptide pleurocidin against most of those screened
The source saysa novel antimicrobial peptide, myxinidin, from the acidic epidermal mucus extract of hagfish (Myxine glutinosa L.) [...] myxinidin consists of 12 amino acids [...] Myxinidin showed activity against a broad range of bacteria and yeast pathogens [...] two to 16 times more active than a potent fish-derived antimicrobial peptide, pleurocidin (NRC-17), against most of the screened pathogens
The page saysThe mucus doubles as an immune barrier
The source saysFish epidermal mucus contains innate immune components that provide a first line of defense against various infectious pathogens.

Source
09

Mincarone 2013

Mincarone (2013). Myxine glutinosa. The IUCN Red List of Threatened Species 2013: e.T196057A8988080.

The page saysLeast Concern
The source saysLeast Concern (LC)Note: category read through GBIF's copy of the Red List; FishBase's mirror of Red List version 2025-2 shows the same category, assessed 12 November 2009, so it is still current
The page saysThe IUCN lists it as Least Concern.
The source saysLeast Concern (LC)Note: category read through GBIF's copy of the Red List

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.