Sphyrna zygaena

The smooth hammerhead is a species of hammerhead shark, and part of the family Sphyrnidae. This species is named "smooth hammerhead" because of the distinctive shape of the head, which is flattened and laterally extended into a hammer shape, without an indentation in the middle of the front margin. Unlike other hammerheads, this species prefers temperate waters and occurs worldwide at medium latitudes. In the summer, these sharks migrate towards the poles following cool water masses, sometimes forming schools numbering in the hundreds to thousands.

Sphyrna zygaena

Uncredited · 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
smooth hammerheadPBDB
Sits inside
SphyrnaPBDB
Diet
carnivorePBDB, for Carcharhiniformes
Life habit
nektonicPBDB, for Carcharhiniformes
Motility
actively mobilePBDB, for Carcharhiniformes

Time the record covers

At least 37 million years on record.

The record covers at least 37.71 Mya to 129 ka. No occurrence read is dated outside 48.07 Mya to 11.7 ka.

Eocene — about 2 of 50 occurrencesEoceneOligocene — about 1 of 50 occurrencesOligoceneMiocene — about 37 of 50 occurrencesMiocenePliocene — about 6 of 50 occurrencesPleistocene — about 4 of 50 occurrences49–47 Mya — about 0.1 occurrences47–46 Mya — about 0.3 occurrences46–44 Mya — about 0.3 occurrences44–42 Mya — about 0.3 occurrences42–41 Mya — about 0.3 occurrences41–39 Mya — about 0.3 occurrences39–38 Mya — about 0.3 occurrences28–26 Mya — about 0.3 occurrences26–25 Mya — about 0.4 occurrences25–23 Mya — about 0.4 occurrences23–21 Mya — about 0.6 occurrences21–20 Mya — about 1 occurrence20–18 Mya — about 2 occurrences18–16 Mya — about 2 occurrences16–15 Mya — about 3 occurrences15–13 Mya — about 4 occurrences13–11 Mya — about 4 occurrences11–9.8 Mya — about 4 occurrences9.8–8.2 Mya — about 4 occurrences8.2–6.5 Mya — about 5 occurrences6.5–4.9 Mya — about 6 occurrences4.9–3.3 Mya — about 4 occurrences3.3–1.6 Mya — about 0.7 occurrences1.6–0 Mya — about 3 occurrences37.71 Mya129 ka49 Mya0 Mya

50 occurrences of Sphyrna zygaena on record, most of them in the Miocene. The Paleobiology Database records this as a living group. 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

50 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

26 formations

Chucunaque — 9.13°N, 78.75°WLagos-Portimão — 37.08°N, 8.28°WLagos-Portimão — 37.08°N, 8.67°WSenhata — 35.16°N, 139.86°EChilcatay — 14.62°S, 75.63°WPalos Verdes Sand — 33.99°N, 118.45°WPalos Verdes Sand — 33.60°N, 117.88°WUrumaco — 11.24°N, 70.25°WUrumaco — 11.23°N, 70.27°WWulagen — 39.69°N, 75.27°EWulagen — 39.60°N, 75.12°EGatun — 9.35°N, 79.80°WYorktown — 35.36°N, 76.82°WPungo River — 35.40°N, 76.80°WTrent — 35.07°N, 77.15°WChandler Bridge — 33.03°N, 80.27°WLuanda — 8.76°S, 13.30°ETirabuzón — 27.37°N, 112.29°WMiramar — 5.19°S, 80.63°WUscari — 9.57°N, 82.57°WVarswater — 33.67°S, 18.43°ECaujarao — 11.50°N, 69.52°WPétervására — 48.24°N, 19.66°ESables des Landes — 43.94°N, 0.75°WSeria — 4.81°N, 114.67°EBhuban — 23.75°N, 92.68°EPisco — 14.35°S, 75.89°WNakazato — 35.45°N, 139.51°E

Loading coastlines…

The named rock units Sphyrna zygaena has been recovered from, largest first. Drawn where the rock is now, not where it formed. 2 further formations hold fewer occurrences each and are not listed. 13 occurrences have no formation on record, which is common for older literature.

Sphyrna zygaena and its relatives

Miocene

Where Sphyrna zygaena and its relatives were recorded in the Miocene.

Found in the same rock

1,663 taxa

The Paleobiology Database records 45 sites for Sphyrna zygaena, 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

34 references

Each of the 50 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. 22 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 Sphyrna zygaena

Credit
nobody named on the record
Licence
not stated by the source
Commercial use
cannot be read from the licence given — check the record

No 3D scan of Sphyrna zygaena 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 itSphyrna through timeFormations of the MioceneThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. (Linnaeus 1758)