Somniosidae

The Somniosidae are a family of sharks in the order Squaliformes, commonly known as sleeper sharks. The common name "sleeper shark" comes from their slow swimming, low activity level, and perceived non-aggressive nature. They lack nictitating membrane and some species are heavily associated with Ommatokoita elongata, potentially bioluminescent parasitic copepod, permanently attached to the corneas, that frequently leave the sharks partially or completely blind. The family is believed to have arose during the Late Cretaceous period roughly 92.29 Ma.

Somniosidae

NOAA Okeanos Explorer Program · 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
sleeper sharkPBDB
Sits inside
SqualiformesPBDB
Diet
carnivorePBDB, for Squaliformes
Life habit
nektonicPBDB, for Squaliformes
Motility
actively mobilePBDB, for Squaliformes

Time the record covers

At least 125 million years on record.

The record covers at least 125.77 Mya to 210 ka. No occurrence read is dated outside 132.6 Mya to 14 ka.

Early Cretaceous — about 1 of 108 occurrencesEarly CretaceousLate Cretaceous — about 55 of 108 occurrencesLate CretaceousPaleocene — about 9 of 108 occurrencesEocene — about 7 of 108 occurrencesEoceneOligocene — about 4 of 108 occurrencesMiocene — about 20 of 108 occurrencesMiocenePliocene — about 6 of 108 occurrencesPleistocene — about 6 of 108 occurrences135–131 Mya — about 0.3 occurrences131–126 Mya — about 0.7 occurrences126–122 Mya — about 0.1 occurrences104–99 Mya — about 0.2 occurrences99–95 Mya — about 0.7 occurrences95–90 Mya — about 1 occurrence90–86 Mya — about 0.1 occurrences86–81 Mya — about 6 occurrences81–77 Mya — about 8 occurrences77–72 Mya — about 8 occurrences72–68 Mya — about 23 occurrences68–63 Mya — about 12 occurrences63–59 Mya — about 4 occurrences59–54 Mya — about 2 occurrences50–45 Mya — about 2 occurrences45–41 Mya — about 3 occurrences41–36 Mya — about 0.9 occurrences36–32 Mya — about 2 occurrences32–27 Mya — about 1 occurrence27–23 Mya — about 2 occurrences23–18 Mya — about 7 occurrences18–14 Mya — about 11 occurrences14–9.0 Mya — about 2 occurrences9.0–4.5 Mya — about 2 occurrences4.5–0 Mya — about 10 occurrences125.77 Mya210 ka135 Mya0 Mya

108 occurrences of Somniosidae 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

108 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

28 formations

Gerhartsreit — 47.80°N, 12.62°EGerhartsreit — 47.94°N, 13.01°ENierental — 47.66°N, 14.86°ELaksarska Nova Ves — 48.59°N, 17.38°EArgille Azzurre — 44.72°N, 10.08°EArgille Azzurre — 44.24°N, 11.76°EArgille Azzurre — 44.28°N, 11.65°EWaipara Greensand — 43.05°S, 172.62°EWaipara Greensand — 43.12°S, 172.48°EStromberg — 51.82°N, 8.19°EByala — 42.88°N, 27.90°EMakino — 34.75°N, 136.27°EMiretrain Marl — 43.57°N, 1.11°WNorthumberland — 49.55°N, 124.70°WNorthumberland — 49.54°N, 124.71°WIseyama — 36.42°N, 138.30°EMishash — 30.87°N, 34.94°EBeckum — 51.79°N, 7.99°ELincoln Creek — 47.30°N, 123.47°WPysht — 48.16°N, 123.90°WRødvig — 55.32°N, 12.44°EMarnes de Miretrain — 43.69°N, 1.13°WEbelsberg — 48.24°N, 13.99°EEbelsberg — 48.21°N, 14.22°ESign — 18.48°N, 77.58°WJoe's River — 13.22°N, 59.55°WPattenau — 47.74°N, 11.47°EPeresheek Mountain — 58.58°N, 163.60°EHigashibessho — 36.60°N, 137.07°E

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The named rock units Somniosidae has been recovered from, largest first. Drawn where the rock is now, not where it formed. 4 further formations hold fewer occurrences each and are not listed. 21 occurrences have no formation on record, which is common for older literature.

Somniosidae and its relatives

Late Cretaceous

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

Found in the same rock

641 taxa

The Paleobiology Database records 79 sites for Somniosidae, 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

39 references

Each of the 108 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. 27 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 content1

Picture of Somniosidae

Credit
NOAA Okeanos Explorer Program
Licence
Public Domain
Commercial use
the licence allows it

No 3D scan of Somniosidae was found in MorphoSource and Sketchfab.

Smithsonian Open Access was not reached for this taxon, so this list is what the others held rather than everything there is.

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 itSqualiformes through timeFormations of the Late CretaceousThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. (Jordan 1888)