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What the sources say

Bobbit WormEunice aphroditois

Every figure, record and mechanism on the Bobbit Worm profile was written from a source, and this is the working table behind it: 41 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

Smithsonian Ocean, Smithsonian Institution

The Bobbit Worm. Smithsonian Ocean, Smithsonian Institution.

The page saysabout ten feet
The source saysup to ten feet long
The page sayssometimes splitting a fish in half
The source sayssometimes splitting its fishy prey in half with its sharp teeth
The page saysWhatever it catches also gets injected with a toxin that helps digest the meal
The source saysIt also injects them with a toxin to help break down its food to make it easier to digest.

Source
02

Lachat & Haag-Wackernagel 2016

Lachat & Haag-Wackernagel (2016). Novel mobbing strategies of a fish population against a sessile annelid predator. Scientific Reports.

The page saysA bobbit worm lives out of sight, in a mucus-lined burrow in rocks or sediment.
The source saysBobbits reside in mucus-lined borrows in rocks or sediments.Note: Framing sentence for the paragraph; the burrow itself is the quoted claim.
The page saysit stays buried in the loose seabed with five striped antennae poking out of the sand
The source saysDuring the day, Bobbits are buried in the loose seabed waiting for a stimulus on one of their five antennae that protrude from the hidden burrow to lure prey fishNote: "Striped" from the same source: "five striped antennae that exhibit wormlike movement".
The page saysThe largest one recorded measured 299 centimeters and weighed 433 grams, and it may be the longest polychaete, a bristly marine worm, on record
The source saysThe largest specimen of a recorded Bobbit worm was 299 cm long, weighing 433 g, and it may be the longest of the polychaete worms
The page saysThese worms live in the sedimentary beds of warmer oceans, including the Indo-Pacific and the Atlantic.
The source saysThe Bobbit worm lives in the sedimentary beds of warmer oceans, including the Indo-Pacific and Atlantic
The page saysit has two eyes on the front of its head
The source saysBobbits have two eyes on the prostomiumNote: The prostomium is the head lobe at the front of the worm.
The page saysResearchers think its five antennae help lure and detect prey
The source saysfive striped antennae that exhibit wormlike movement and presumably serve to lure and detect prey
The page saysit detects a meal mainly by sight and touch
The source saysBobbits appear to detect their prey mainly by visual and tactile cues.
The page saysBy day it waits for something to brush an antenna
The source saysDuring the day, Bobbits are buried in the loose seabed waiting for a stimulus on one of their five antennae that protrude from the hidden burrow to lure prey fish
The page saysAt night it changes tactics and actively hunts, poking out of its burrow to snatch passing prey
The source saysAt night, the Bobbit changes its strategy and actively hunts by protruding from its burrow and snatching passing prey.
The page saysthe worm's jaws sit "under tension like an armed spring trap"
The source saysthe jaws are under tension like an armed spring trap
The page saysthe whole ambush, from snatch to the worm vanishing back underground, took about a tenth of a second
The source saysThe entire process from the snatching of a prey until complete disappearance lasted approximately 0.1 s.Note: Measured across the filmed predation events in the mobbing study, not a species-wide claim; the sentence says "In the attacks researchers filmed".
The page saysBobbit worms are known to bite humans and can cause severe wounds.
The source saysBobbits are known to bite humans and can cause severe wounds.
The page saysA fish called *Scolopsis affinis*, which feeds near the seabed, turns on its hunter: when one spots a hidden bobbit worm, it blasts jets of water into the burrow, and others often join in
The source saysThe fish direct sharp water jets towards the hidden sessile annelid predator Eunice aphroditois (Bobbit worm)Note: S. affinis is "a common demersal species that lives and feeds near the seabed of the western Pacific". Joining: "S. affinis individuals either mob alone or form mobbing groups."
The page saysResearchers diving in Indonesia filmed 46 of these water-jet attacks. In 16 of them, the worm reacted by pulling in an antenna or retreating completely into its burrow
The source saysDuring the remaining 46 observations, S. affinis directed water jets at the Bobbit ... in 16 observations (34.8%), the Bobbit showed a visible reaction by retracting an antenna or completely retracting into its burrow.Note: Dive site named in Methods: Air Prang, Lembeh Strait, Sulawesi, Indonesia.
The page saysAn ambush predator up to ten feet long that buries itself in the sand with its jaws cocked like a spring trap, ready to snap a passing fish in half.
The source saysthe jaws are under tension like an armed spring trapNote: "Up to ten feet" is the smithsonian claim above; "snap a passing fish in half" is the smithsonian splitting claim above.
The page saysIt lies buried in its burrow with its jaws "under tension like an armed spring trap," then snatches a fish and is gone in about a tenth of a second
The source saysthe jaws are under tension like an armed spring trapNote: The tenth of a second is the same 0.1 s claim above: snatch to complete disappearance, not the strike alone.
The page saysThe largest one recorded measured 299 centimeters, just under ten feet, and weighed 433 grams, which may make it the longest polychaete, or bristle worm, on record
The source saysThe largest specimen of a recorded Bobbit worm was 299 cm long, weighing 433 g, and it may be the longest of the polychaete wormsNote: "Just under ten feet" is 299 cm converted.
The page saysThe worm stays buried in the loose seabed, with five striped antennae protruding from the burrow to lure prey fish
The source saysDuring the day, Bobbits are buried in the loose seabed waiting for a stimulus on one of their five antennae that protrude from the hidden burrow to lure prey fish
The page saysNo. It actually has two eyes on its head, in addition to its five antennae
The source saysBobbits have two eyes on the prostomium
The page saysResearchers think the antennae help lure and detect prey, and that the worm detects a meal mainly by sight and touch.
The source saysfive striped antennae that exhibit wormlike movement and presumably serve to lure and detect preyNote: "Detects a meal mainly by sight and touch" is the same visual/tactile cues claim above.
The page saysBuried in sediment on the sea floor of warm waters across the Indo-Pacific and Atlantic.
The source saysThe Bobbit worm lives in the sedimentary beds of warmer oceans, including the Indo-Pacific and Atlantic
The page saysNot Evaluated
The source saysthe hidden sessile annelid predator Eunice aphroditois (Bobbit worm)Note: stats.conservationStatus. No reference in the profile states a Red List status; this quote anchors the species name only. GBIF's copy of the Red List returns NOT_EVALUATED for Eunice aphroditois (Pallas, 1788), usage key 5198482 (https://api.gbif.org/v1/species/5198482/iucnRedListCategory), checked 2026-09-17, and source:prefetch found no Crossref assessment DOI under this name (2026-09-15). The house convention for an unassessed species is to carry no status reference (#596).
The page saystags: invertebrate
The source saysthe hidden sessile annelid predator Eunice aphroditois (Bobbit worm)Note: Replaces the `mammal` tag (#596). Eunice aphroditois is an annelid, a polychaete worm, so it has no backbone: the tag reads "Animals lacking a backbone or spinal column". The same paper calls it "the longest of the polychaete worms".
The page saystags: benthic
The source saysThe Bobbit worm lives in the sedimentary beds of warmer oceansNote: Replaces the `coral-reef` tag (#596), whose definition is navigating "complex limestone reef structures". The tag reads "Living on the bottom of aquatic bodies, crawling over sediments, rocky reefs, and seabed deposits", and the same paper adds "Bobbits reside in mucus-lined borrows in rocks or sediments".

Source
03

Pan et al. 2021

Pan et al. (2021). The 20-million-year old lair of an ambush-predatory worm preserved in northeast Taiwan. Scientific Reports.

The page sayson a body up to two centimeters across
The source saysBobbit worms can grow up to 3 m long and 2 cm in diameterNote: The Smithsonian page says "a couple inches wide" (about 5 cm); Pan et al. give 2 cm, and the Pennichnus burrows are 2-3 cm in diameter, so the paper's figure is used.
The page saysIt rapidly thrusts out an eversible pharynx, a throat that turns inside out to strike, tipped with sharp maxillae
The source saysthe Bobbit worm rapidly thrusts out of its burrow and grabs the prey with its eversible pharynx and sharp maxillae
The page saysscientists described a fossil burrow up to two meters long, L-shaped, with distinct feather-like structures around its upper shaft
The source saysThis trace fossil consists of an up to 2 m long, 2–3 cm in diameter, L-shaped burrow with distinct feather-like structures around the upper shaft.Note: Pennichnus is a trace fossil, a burrow, not a body fossil.
The page saysits shape strongly suggests ambush-predatory worms that lived about 20 million years ago
The source saysA comparison of Pennichnus to biological analogs strongly suggests that this new ichnogenus is associated with ambush-predatory worms that lived about 20 million years ago.Note: The paper's own verb is "strongly suggests", and it names no species: the sentence claims no more.
The page saysFish, bivalves, and other segmented worms.
The source saysThey are ambush predators that feed on fish, bivalves, and other annelids
The page saysAn eversible pharynx tipped with sharp maxillae that thrusts out of its burrow fast enough to split a passing fish in half, with five antennae and two eyes to detect prey.
The source saysthe Bobbit worm rapidly thrusts out of its burrow and grabs the prey with its eversible pharynx and sharp maxillaeNote: Antennae/eyes covered by the novel-2016 claims above; splitting prey in half by the smithsonian claim above.
The page saysit rapidly thrusts out an eversible pharynx, a throat that turns inside out to strike, tipped with sharp maxillae, its jaw pincers, and grabs the fish
The source saysthe Bobbit worm rapidly thrusts out of its burrow and grabs the prey with its eversible pharynx and sharp maxillae
The page saysThe still living animal is then dragged down into the burrow to be eaten.
The source saysThe still living animal is then dragged down into the burrow for consumption
The page saystags: ambush-predator
The source saysThey are ambush predators that feed on fish, bivalves, and other annelidsNote: Replaces the `super-bite-force` tag (#596): no source states a bite force, and an annelid has neither the "jaw adductor musculature" nor the "reinforced skull bones" that tag names. The same paper: "They hide in their burrows until they explode upwards grabbing unsuspecting prey with a snap of their powerful jaws".

Source
04

Shinomiya et al. 2023

Shinomiya et al. (2023). Molecular and Morphological Assessment of Juvenile and Adult Forms in the Giant Worm Eunice Cf. Aphroditois (Annelida: Eunicidae) and Its Phylogenetic Position in the Family. Zoological Science.

The page sayscan grow up to three meters long
The source saysa large polychaete worm (up to 3 m in length)Note: The abstract states this length for Eunice aphroditois itself, before the paper turns to the separate Japanese Eunice cf. aphroditois form.

Source
05

Eriksson, Parry & Rudkin 2017

Eriksson, Parry & Rudkin (2017). Earth’s oldest ‘Bobbit worm’ – gigantism in a Devonian eunicidan polychaete. Scientific Reports.

The page says400-million-year-old rocks in Canada preserve fossil jaws over a centimeter long from *Websteroprion armstrongi*, an extinct bristle worm with a body estimated at more than a meter long
The source saysWebsteroprion armstrongi was a raptorial feeder and possessed the largest jaws recorded in polychaetes from the fossil record, with maxillae reaching over one centimetre in length. Total body length of the species is estimated to have reached over one metre ... some 400 million years ago.Note: A Devonian eunicidan polychaete from Ontario, Canada: a fossil relative, not Eunice aphroditois.
The page saysthat ancient one's feeding habits remain unclear
The source saysmore precise knowledge of the feeding habits of W. armstrongi remains elusive for the time being
The page saysThere are published claims of individuals in the genus Eunice reaching 6 meters, but some authors have argued that they are rather in the order of 3 meters.
The source saysthere are published claims of individuals reaching 6 m in length ...; however, some authors have argued that they are rather in the order of 3 mNote: The dispute is about the genus Eunice generally, which the answer says.
The page saysEunice aphroditois, the bobbit worm, is the largest species known in that genus.
The source saysThe largest species known is the famous ambush predator Eunice aphroditoisNote: The same paper adds that the taxonomy of this species (or species complex) is controversial.

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.