Hexanchus

The sixgill sharks are a genus, Hexanchus, of deepwater sharks in the family Hexanchidae. These sharks are characterized by a broad, pointed head, six pairs of gill slits, comb-like, yellow lower teeth, and a long tail. The largest species can grow up to 8 m (26 ft) long and weigh over 600 kg (1,300 lb). They are continental shelf-dwelling and abyssal plain scavengers with a keen sense of smell and are among the first to arrive at carrion, together with hagfish and rattails. They show a characteristic rolling motion of the head when feeding.

A picture published with the record for Hexanchus.

NOAA · Public Domain · via Wikipedia/Commons. May be a photograph of a specimen, or an artist’s reconstruction — an interpretation of a skeleton, since colour and soft tissue are almost never preserved.

On record

Recorded, not inferred
Also called
sixgill sharkPBDB
Sits inside
HexanchidaePBDB
Diet
carnivorePBDB, for Hexanchiformes
Life habit
nektonicPBDB, for Hexanchiformes
Motility
actively mobilePBDB, for Hexanchiformes

Time the record covers

At least 111 million years on record.

The record covers at least 113.2 Mya to 1.8 Mya. No occurrence read is dated outside 121.4 Mya to 774 ka.

Early Cretaceous — about 2 of 177 occurrencesEarly CretaceousLate Cretaceous — about 52 of 177 occurrencesLate CretaceousPaleocene — about 13 of 177 occurrencesEocene — about 50 of 177 occurrencesEoceneOligocene — about 9 of 177 occurrencesOligoceneMiocene — about 37 of 177 occurrencesMiocenePliocene — about 12 of 177 occurrencesPleistocene — about 2 of 177 occurrences124–120 Mya — about 0.2 occurrences120–116 Mya — about 0.5 occurrences116–111 Mya — about 0.3 occurrences107–103 Mya — about 0.5 occurrences103–99 Mya — about 1 occurrence99–95 Mya — about 3 occurrences95–91 Mya — about 2 occurrences91–87 Mya — about 3 occurrences87–83 Mya — about 11 occurrences83–78 Mya — about 7 occurrences78–74 Mya — about 7 occurrences74–70 Mya — about 9 occurrences70–66 Mya — about 11 occurrences66–62 Mya — about 11 occurrences62–58 Mya — about 2 occurrences58–54 Mya — about 3 occurrences54–50 Mya — about 4 occurrences50–45 Mya — about 7 occurrences45–41 Mya — about 9 occurrences41–37 Mya — about 12 occurrences37–33 Mya — about 17 occurrences33–29 Mya — about 4 occurrences29–25 Mya — about 3 occurrences25–21 Mya — about 3 occurrences21–17 Mya — about 3 occurrences17–12 Mya — about 14 occurrences12–8.3 Mya — about 11 occurrences8.3–4.1 Mya — about 14 occurrences4.1–0 Mya — about 7 occurrences113.2 Mya1.8 Mya124 Mya0 Mya

177 occurrences of Hexanchus on record, most of them in the Late Cretaceous. The Paleobiology Database records this as a living group, and the chart stops with its fossils rather than at the present. Bar height is expected occurrences, not a count: each fossil is spread across the span it is dated to, so a tall narrow bar means tight dating and a low wide one means loose.

When

177 occurrences

These are dates about fossils, not the animal: the record can only begin after it arose and end before it died out, so either end may reach further. Shares are expected occurrences: a fossil dated to a span is counted partly in each period it straddles. More on what this infers.

Found in

85 formations

Gehannam — 29.36°N, 30.16°EGehannam — 29.33°N, 30.08°EGehannam — 29.32°N, 30.17°EGehannam — 29.30°N, 30.05°EMarnes de Donzacq — 43.75°N, 0.84°WYamaga — 33.99°N, 130.82°EHornerstown — 40.10°N, 73.00°WHornerstown — 39.76°N, 75.13°WBirket Qarun — 29.27°N, 30.06°EBirket Qarun — 29.28°N, 30.03°EGerhartsreit — 47.94°N, 13.01°EKattendijk — 51.26°N, 4.27°EMishash — 30.87°N, 34.94°EMishash — 30.83°N, 35.08°EMishash — 30.83°N, 34.92°ELa Meseta — 64.24°S, 56.65°WHinoshima — 32.40°N, 130.40°ERío Baguales — 50.73°S, 72.47°WLondon Clay — 51.40°N, 0.83°ELondon Clay — 51.64°N, 0.78°EJewett — 35.49°N, 118.85°WWadi Esh-Shallala — 31.57°N, 37.12°EWadi Esh-Shallala — 30.85°N, 35.85°EBreda — 52.15°N, 6.61°EBreda — 51.47°N, 5.80°ENewhaven Chalk — 51.45°N, 1.36°WNewhaven Chalk — 50.67°N, 1.10°WGhared — 30.83°N, 35.08°ENorthumberland — 49.55°N, 124.70°WNorthumberland — 49.54°N, 124.71°WOiching — 47.94°N, 13.01°ERødvig — 55.32°N, 12.44°EHorcón — 32.70°S, 71.46°WAshizawa — 37.20°N, 140.95°ELagos-Portimão — 37.12°N, 8.54°WLagos-Portimão — 37.08°N, 8.67°WLillebælt Clay — 55.60°N, 9.80°E

Loading coastlines…

The named rock units Hexanchus has been recovered from, largest first. Drawn where the rock is now, not where it formed. 61 further formations hold fewer occurrences each and are not listed. 40 occurrences have no formation on record, which is common for older literature.

Hexanchus and its relatives

Late Cretaceous

Where Hexanchus and its relatives were recorded in the Late Cretaceous.

Found in the same rock

2,014 taxa

The Paleobiology Database records 155 sites for Hexanchus, and this reads all of them. The number is how many of those sites it was catalogued from too. The 24 sharing the most are listed.

This is not a list of everything alive at the time. It is only what has come out of the same ground as this animal and been written down.

Entered from

107 references

Each of the 177 occurrences read was entered from one of these publications, ordered by how many each accounts for. This is not a search for papers mentioning the name. 95 further references are not listed. Entries link to doi.org where the Paleobiology Database holds an identifier, and to its own record where it does not. Relayed as the Paleobiology Database holds them, not checked against what they resolve to.

Media and terms

Media content3

Picture of Hexanchus

Credit
NOAA
Licence
Public Domain
Commercial use
the licence allows it

CT scan

Licence
not stated by the source
Commercial use
cannot be read from the licence given — check the record
Specimen
Hexanchus vitulus · uf:fish:246748

3D model

Source
Sketchfab
Licence
CC Attribution-NonCommercial
Commercial use
the licence does not allow it

The description on this site

Licence
CC BY-SA 4.0

This is what the site found, which is not the same as what exists.

Keep going

What may have been alongside itHexanchidae through timeFormations of the Late CretaceousThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. (Rafinesque 1810)