Raja

Raja, also known as Raia, is a genus of skates in the family Rajidae containing 16 species. Formerly a wastebasket genus, many species historically categorized here have been moved to other genera in the family, such as Amblyraja, Beringraja, Dipturus, Leucoraja and Rostroraja. Raja are flat-bodied, cartilaginous fish with rhombic shapes due to their large pectoral fins extending from or near from the snouts to the bases of their tails. Their sharp snouts are produced by a cranial projection of rostral cartilage. The mouth and gills are located on the underside of the body. They may be either solid-coloured or patterned, and most skates have spiny or thornlike structures on the upper surface, while some species contain weak electrical organs within their tails. Mating typically occurs in the spring and the female lays numerous eggs per clutch which are encapsulated in leathery cases, commonly known as "mermaid’s purses". Species vary in size, ranging from about 40 to 140 cm (1.3–4.6 ft) in length. These bottom-dwellers are active during both day and night, and typically feed on molluscs, crustaceans and fish. Raja skates are found in the East Atlantic, also in the Mediterranean, and western Indian Ocean, ranging from relatively shallow water to a depth of 800 m (2,600 ft). Skates and related species have fossil records dating from the Upper Cretaceous period, thus this well-adapted lineage is quite ancient.

A picture published with the record for Raja.

Hans Hillewaert · CC BY-SA 4.0 · 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
RajidaePBDB
Diet
carnivorePBDB, for Rajiformes
Life habit
nektobenthicPBDB, for Rajiformes
Motility
actively mobilePBDB, for Rajiformes

Time the record covers

At least 201 million years on record.

The record covers at least 201.4 Mya to 11.7 ka. No occurrence read is dated outside 205.7 Mya to 0 Mya.

Late Triassic — about 1 of 174 occurrencesEarly Jurassic — about 0 of 174 occurrencesMiddle Jurassic — about 0 of 174 occurrencesLate Jurassic — about 0 of 174 occurrencesEarly Cretaceous — about 0 of 174 occurrencesLate Cretaceous — about 8 of 174 occurrencesLate CretaceousPaleocene — about 2 of 174 occurrencesEocene — about 26 of 174 occurrencesEoceneOligocene — about 44 of 174 occurrencesMiocene — about 56 of 174 occurrencesMiocenePliocene — about 22 of 174 occurrencesPleistocene — about 14 of 174 occurrences210–203 Mya — about 0.7 occurrences203–196 Mya — about 0.3 occurrences91–84 Mya — about 0.8 occurrences84–77 Mya — about 0.2 occurrences77–70 Mya — about 3 occurrences70–63 Mya — about 4 occurrences63–56 Mya — about 2 occurrences56–49 Mya — about 4 occurrences49–42 Mya — about 10 occurrences42–35 Mya — about 12 occurrences35–28 Mya — about 35 occurrences28–21 Mya — about 10 occurrences21–14 Mya — about 20 occurrences14–7.0 Mya — about 29 occurrences7.0–0 Mya — about 44 occurrences201.4 Mya11.7 ka210 Mya0 Mya

174 occurrences of Raja 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

174 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

58 formations

Boom Clay — 51.13°N, 4.26°EBoom Clay — 51.12°N, 4.35°EBoom Clay — 51.19°N, 4.32°EBoom Clay — 51.16°N, 4.13°EMarnes de Donzacq — 43.75°N, 0.84°WBerchem — 51.20°N, 4.44°EArenas de Huelva — 37.33°N, 6.68°WArenas de Huelva — 37.35°N, 6.61°WArenas de Huelva — 37.27°N, 6.84°WPalos Verdes Sand — 33.76°N, 118.29°WPalos Verdes Sand — 33.66°N, 117.90°WPalos Verdes Sand — 33.99°N, 118.45°WPalos Verdes Sand — 33.75°N, 118.29°WLa Meseta — 64.23°S, 56.65°WEsbarrondadoiro — 38.17°N, 8.17°WEsbarrondadoiro — 38.11°N, 8.36°WEsbarrondadoiro — 39.30°N, 8.12°WAshley — 32.95°N, 80.18°WAshley — 32.97°N, 80.20°WDongen — 52.73°N, 6.30°EDongen — 53.16°N, 6.22°EOosterhout — 51.70°N, 5.73°EBreda — 52.15°N, 6.61°EBreda — 51.70°N, 5.73°EBreda — 51.47°N, 5.80°EPort Orford — 42.83°N, 124.55°WNeuhofen — 48.50°N, 14.28°ERupel — 51.22°N, 12.33°EChandler Bridge — 33.03°N, 80.27°WHrušky — 48.81°N, 16.63°ECalvert — 38.16°N, 76.83°WBahía Inglesa — 26.22°S, 70.72°WBahía Inglesa — 27.16°S, 70.89°WLagos-Portimão — 37.12°N, 8.54°WLagos-Portimão — 37.08°N, 8.67°WSternberg — 53.67°N, 11.82°ESubmeseta — 64.23°S, 56.60°WCubagua — 10.57°N, 64.24°WVarswater — 32.98°S, 18.15°EClinchfield — 32.91°N, 83.36°W

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The named rock units Raja has been recovered from, largest first. Drawn where the rock is now, not where it formed. 34 further formations hold fewer occurrences each and are not listed. 34 occurrences have no formation on record, which is common for older literature.

Raja and its relatives

Miocene

Where Raja and its relatives were recorded in the Miocene.

Found in the same rock

2,093 taxa

The Paleobiology Database records 150 sites for Raja, 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

81 references

Each of the 174 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. 69 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 content2

Picture of Raja

Credit
Hans Hillewaert
Licence
CC BY-SA 4.0
Commercial use
the licence allows it

Sequential Section Scan

Licence
In Copyright
Commercial use
cannot be read from the licence given — check the record
Specimen
Raja eglanteria · MCZ:SC:3784

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 itRajidae through timeFormations of the MioceneThe world it lived on

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