Carcharhinus falciformis

The silky shark, also known by numerous names such as blackspot shark, gray whaler shark, olive shark, ridgeback shark, sickle shark, sickle-shaped shark and sickle silk shark, is a species of requiem shark, in the family Carcharhinidae, named for the smooth texture of its skin. It is one of the most abundant sharks in the pelagic zone, and can be found around the world in tropical waters. Highly mobile and migratory, this shark is most often found over the edge of the continental shelf down to 50 m (164 ft). The silky shark has a slender, streamlined body and typically grows to a length of 2.5 m. It can be distinguished from other large requiem sharks by its relatively small first dorsal fin with a curving rear margin, its tiny second dorsal fin with a long free rear tip, and its long, sickle-shaped pectoral fins. It is a deep, metallic bronze-gray above and white below.

Carcharhinus falciformis

Alex Chernikh · CC BY 2.5 · 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
silky sharkPBDB
Sits inside
CarcharhinusPBDB
Diet
carnivorePBDB, for Carcharhiniformes
Life habit
nektonicPBDB, for Carcharhiniformes
Motility
actively mobilePBDB, for Carcharhiniformes

Time the record covers

At least 17 million years on record.

The record covers at least 20.45 Mya to 2.58 Mya. No occurrence read is dated outside 23.04 Mya to 0 Mya.

Oligocene — about 0 of 23 occurrencesMiocene — about 16 of 23 occurrencesMiocenePliocene — about 6 of 23 occurrencesPliocenePleistocene — about 1 of 23 occurrencesPleistocene24–23 Mya — about 0.2 occurrences23–22 Mya — about 0.4 occurrences22–21 Mya — about 0.4 occurrences21–20 Mya — about 0.5 occurrences20–20 Mya — about 0.8 occurrences20–19 Mya — about 0.8 occurrences19–18 Mya — about 0.8 occurrences18–17 Mya — about 0.8 occurrences17–16 Mya — about 0.8 occurrences16–16 Mya — about 0.6 occurrences16–15 Mya — about 0.1 occurrences15–14 Mya — about 0.1 occurrences14–13 Mya — about 0.4 occurrences13–13 Mya — about 0.5 occurrences13–12 Mya — about 0.5 occurrences12–11 Mya — about 1.0 occurrences11–10 Mya — about 1 occurrence10–9.4 Mya — about 1 occurrence9.4–8.6 Mya — about 1 occurrence8.6–7.8 Mya — about 1 occurrence7.8–7.1 Mya — about 1.0 occurrences7.1–6.3 Mya — about 0.8 occurrences6.3–5.5 Mya — about 0.8 occurrences5.5–4.7 Mya — about 2 occurrences4.7–3.9 Mya — about 3 occurrences3.9–3.1 Mya — about 1 occurrence3.1–2.4 Mya — about 0.5 occurrences2.4–1.6 Mya — about 0.3 occurrences1.6–785 ka Mya — about 0.3 occurrences785 ka–0 Mya — about 0.3 occurrences20.45 Mya2.58 Mya23.5 Mya0 Mya

23 occurrences of Carcharhinus falciformis 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

23 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

12 formations

Globigerina Limestone — 36.08°N, 14.24°EGlobigerina Limestone — 35.90°N, 14.33°EGatun — 9.35°N, 79.84°WGatun — 9.34°N, 79.82°WChucunaque — 9.13°N, 78.75°WPungo River — 35.40°N, 76.80°WCastillo — 10.37°N, 70.07°WTirabuzón — 27.37°N, 112.29°WBlue Clay — 35.93°N, 14.34°EMiramar — 5.19°S, 80.63°WUscari — 9.57°N, 82.57°WSeria — 4.81°N, 114.67°ECantaure — 11.93°N, 70.01°WYorktown — 33.58°N, 77.42°W

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The named rock units Carcharhinus falciformis has been recovered from, largest first. Drawn where the rock is now, not where it formed. 7 occurrences have no formation on record, which is common for older literature.

Carcharhinus falciformis and its relatives

Miocene

Where Carcharhinus falciformis and its relatives were recorded in the Miocene.

Found in the same rock

308 taxa

The Paleobiology Database records 20 sites for Carcharhinus falciformis, 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

17 references

Each of the 23 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. 5 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 Carcharhinus falciformis

Credit
Alex Chernikh
Licence
CC BY 2.5
Commercial use
the licence allows it

CT scan

Licence
In Copyright
Commercial use
cannot be read from the licence given — check the record
Specimen
Carcharhinus falciformis · MCZ:Ich:153592

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 itCarcharhinus through timeFormations of the MioceneThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. (Muller and Henle 1839)