Hydrolycus

Hydrolycus is a genus of freshwater ray-finned fishes belonging to the family Cynodontidae, the dogtooth characins. These fishes are found in tropical South America, where found in the Amazon and Orinoco basins, as well as rivers of the Guianas. The genus includes the largest dogtooth characins, reaching up to 1.17 m (3.8 ft) in length. They have long, pointed teeth used for spearing their prey, generally smaller fish. In a study of the stomachs of 45 individuals, most were empty, but among the remaining the prey fish were 15–50% of the length Hydrolycus itself.

Hydrolycus

Uncredited · CC BY-SA 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
Sits inside
CynodontidaePBDB
Motility
actively mobilePBDB, for Osteichthyes
Environment
freshwaterPBDB, for Characiformes

Time the record covers

At least 34 million years on record.

The record covers at least 37.71 Mya to 3.6 Mya. No occurrence read is dated outside 48.07 Mya to 2.58 Mya.

Eocene — about 3 of 23 occurrencesEoceneOligocene — about 10 of 23 occurrencesOligoceneMiocene — about 8 of 23 occurrencesMiocenePliocene — about 2 of 23 occurrencesPleistocene — about 0 of 23 occurrences49–47 Mya — about 0.1 occurrences47–46 Mya — about 0.2 occurrences46–44 Mya — about 0.2 occurrences44–43 Mya — about 0.2 occurrences43–41 Mya — about 0.2 occurrences41–40 Mya — about 0.2 occurrences40–38 Mya — about 0.2 occurrences38–36 Mya — about 0.7 occurrences36–35 Mya — about 0.8 occurrences35–33 Mya — about 1 occurrence33–32 Mya — about 1 occurrence32–30 Mya — about 1 occurrence30–28 Mya — about 1 occurrence28–27 Mya — about 1 occurrence27–25 Mya — about 2 occurrences25–24 Mya — about 2 occurrences24–22 Mya — about 0.7 occurrences22–21 Mya — about 0.1 occurrences21–19 Mya — about 0.5 occurrences19–17 Mya — about 0.4 occurrences17–16 Mya — about 0.0 occurrences16–14 Mya — about 0.4 occurrences14–13 Mya — about 1 occurrence13–11 Mya — about 2 occurrences11–9.6 Mya — about 1 occurrence9.6–8.0 Mya — about 1 occurrence8.0–6.4 Mya — about 0.6 occurrences4.8–3.2 Mya — about 0.7 occurrences3.2–1.7 Mya — about 1 occurrence37.71 Mya3.6 Mya49 Mya1.7 Mya

23 occurrences of Hydrolycus on record, most of them in the Oligocene. 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

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

6 formations

Pozo — 7.33°S, 74.95°WPozo — 6.57°S, 76.27°WPebas — 7.36°S, 74.96°WChambira — 7.32°S, 74.93°WChambira — 7.35°S, 74.96°WWare — 11.85°N, 71.32°WLa Victoria — 3.33°N, 75.15°WVillavieja — 3.22°N, 75.14°W

Loading coastlines…

The named rock units Hydrolycus has been recovered from, largest first. Drawn where the rock is now, not where it formed.

Hydrolycus and its relatives

Oligocene

Where Hydrolycus and its relatives were recorded in the Oligocene.

Found in the same rock

223 taxa

The Paleobiology Database records 21 sites for Hydrolycus, 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

4 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. 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 content2

Picture of Hydrolycus

Credit
nobody named on the record
Licence
CC BY-SA 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
Hydrolycus armatus · ROM:Fishes:88356

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 itCynodontidae through timeFormations of the OligoceneThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Lundberg 1997