Brachyura

Brachyura is an infraorder of decapod crustaceans comprising the true crabs. They typically have a very short projecting tail-like abdomen, usually hidden entirely under the thorax. Their exoskeleton is often thickened and hard. They generally have five pairs of legs, and the frontmost pair end in chelae, which function as pincers. They are present in all the world's oceans, in freshwater, and on land, often hiding themselves in small crevices or burrowing into sediment. True crabs are omnivores, feeding on a variety of food, including a significant proportion of algae, as well as detritus and other invertebrates. True crabs are widely consumed by humans as food, with over 1.5 million tonnes caught annually.

Brachyura

Biopics Dan Boone Honguyenseo Bernard Picton Biopics Philippe Boujon Splette Nosferattus Rushenb · 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
Also called
crabPBDB
Sits inside
MeiuraPBDB
Diet
carnivorePBDB, for Decapoda
Life habit
epifaunalPBDB, for Decapoda
Motility
actively mobilePBDB, for Malacostraca
Vision
well-developedPBDB, for Malacostraca

Time the record covers

At least 293 million years on record.

The record covers at least 293.52 Mya to 11.7 ka. No occurrence read is dated outside 298.9 Mya to 0 Mya.

Carboniferous — about 0 of 5471 occurrencesPermian — about 1 of 5471 occurrencesPermianEarly Triassic — about 0 of 5471 occurrencesMiddle Triassic — about 0 of 5471 occurrencesLate Triassic — about 1 of 5471 occurrencesLate TriassicEarly Jurassic — about 2 of 5471 occurrencesEarly JurassicMiddle Jurassic — about 25 of 5471 occurrencesLate Jurassic — about 160 of 5471 occurrencesEarly Cretaceous — about 273 of 5471 occurrencesEarly CretaceousLate Cretaceous — about 624 of 5471 occurrencesLate CretaceousPaleocene — about 164 of 5471 occurrencesEocene — about 1541 of 5471 occurrencesOligocene — about 315 of 5471 occurrencesMiocene — about 1323 of 5471 occurrencesPliocene — about 327 of 5471 occurrencesPleistocene — about 526 of 5471 occurrences305–295 Mya — about 0.8 occurrences295–285 Mya — about 0.2 occurrences234–224 Mya — about 0.2 occurrences224–213 Mya — about 0.5 occurrences213–203 Mya — about 0.4 occurrences203–193 Mya — about 0.7 occurrences193–183 Mya — about 0.9 occurrences183–173 Mya — about 1 occurrence173–163 Mya — about 21 occurrences163–152 Mya — about 69 occurrences152–142 Mya — about 94 occurrences142–132 Mya — about 5 occurrences132–122 Mya — about 17 occurrences122–112 Mya — about 94 occurrences112–102 Mya — about 136 occurrences102–91 Mya — about 201 occurrences91–81 Mya — about 107 occurrences81–71 Mya — about 173 occurrences71–61 Mya — about 259 occurrences61–51 Mya — about 367 occurrences51–41 Mya — about 745 occurrences41–30 Mya — about 602 occurrences30–20 Mya — about 338 occurrences20–10 Mya — about 796 occurrences10–0 Mya — about 1442 occurrences293.52 Mya11.7 ka305 Mya0 Mya

5,471 occurrences of Brachyura on record, most of them in the Eocene. 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

5,471 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

639 formations

Sandakan — 5.86°N, 118.04°ESandakan — 5.88°N, 118.06°ESandakan — 5.85°N, 118.07°ECercado — 19.47°N, 71.08°WCercado — 19.46°N, 71.19°WPalos Verdes Sand — 33.80°N, 118.16°WPalos Verdes Sand — 33.99°N, 118.45°WPalos Verdes Sand — 33.60°N, 117.88°WPalos Verdes Sand — 33.75°N, 118.29°WPalos Verdes Sand — 33.78°N, 118.30°WPalos Verdes Sand — 33.97°N, 118.42°WPalos Verdes Sand — 32.72°N, 117.26°WPalos Verdes Sand — 34.04°N, 118.57°WPalos Verdes Sand — 32.70°N, 117.19°WPirabas — 1.18°S, 47.22°WPirabas — 0.82°S, 46.96°WPirabas — 0.48°S, 48.17°WPirabas — 1.05°S, 47.16°WPirabas — 0.60°S, 47.31°WPirabas — 0.84°S, 47.09°WPirabas — 2.58°S, 43.38°WSan Pedro — 33.93°N, 117.95°WSan Pedro — 33.80°N, 118.17°WSan Pedro — 32.67°N, 117.14°WSan Pedro — 33.74°N, 118.29°WSan Pedro — 33.75°N, 118.29°WMiri — 4.82°N, 114.75°EMiri — 4.86°N, 114.80°ELa Meseta — 64.24°S, 56.60°WLa Meseta — 64.24°S, 56.66°WLa Meseta — 64.25°S, 56.71°WLookingglass — 42.56°N, 124.02°WLookingglass — 43.16°N, 123.96°WLookingglass — 43.03°N, 123.64°WLookingglass — 43.30°N, 123.10°WPierre Shale — 43.25°N, 104.27°WPierre Shale — 40.73°N, 105.03°WPierre Shale — 43.92°N, 102.70°WPierre Shale — 43.92°N, 102.98°WPierre Shale — 45.53°N, 100.43°WPierre Shale — 43.73°N, 102.76°WPierre Shale — 45.54°N, 100.50°WPierre Shale — 45.64°N, 100.74°WPierre Shale — 46.22°N, 104.02°WPierre Shale — 43.05°N, 104.42°WPierre Shale — 46.92°N, 104.71°WPierre Shale — 46.78°N, 104.49°WPierre Shale — 40.20°N, 105.29°WPierre Shale — 43.23°N, 103.21°WPierre Shale — 44.98°N, 104.02°WPierre Shale — 46.96°N, 104.77°WPierre Shale — 44.47°N, 100.61°WPierre Shale — 44.04°N, 99.52°WPierre Shale — 44.70°N, 103.26°WPierre Shale — 44.78°N, 103.90°WPierre Shale — 43.91°N, 102.91°WDomanda — 31.33°N, 70.15°EDomanda — 29.97°N, 70.12°EDomanda — 30.87°N, 70.22°EDomanda — 30.13°N, 70.37°EDomanda — 29.93°N, 70.12°EDomanda — 30.98°N, 70.22°EDomanda — 30.77°N, 70.46°EDomanda — 31.61°N, 70.19°EErnstbrunn — 48.54°N, 16.36°EErnstbrunn — 48.55°N, 16.35°ECasimcea — 44.50°N, 28.42°ECasimcea — 44.47°N, 28.48°ECasimcea — 44.56°N, 28.04°ECasimcea — 44.40°N, 28.56°ENdalithoni — 17.24°S, 178.94°WLondon Clay — 51.40°N, 0.83°ELondon Clay — 51.73°N, 0.48°ELondon Clay — 51.51°N, 0.24°ELondon Clay — 51.37°N, 1.14°WLondon Clay — 51.42°N, 0.90°ELondon Clay — 51.63°N, 0.78°ELondon Clay — 51.70°N, 0.76°ELondon Clay — 51.58°N, 0.15°WLondon Clay — 50.78°N, 0.70°WBateque — 26.75°N, 113.00°WBateque — 26.95°N, 113.06°WBateque — 26.94°N, 113.07°WBateque — 26.45°N, 113.00°WBateque — 26.42°N, 112.58°WBateque — 24.17°N, 110.92°WBateque — 26.70°N, 112.97°WCastle Hayne — 34.64°N, 77.65°WCastle Hayne — 34.63°N, 77.75°WCastle Hayne — 34.37°N, 77.84°WCastle Hayne — 34.40°N, 77.86°WCastle Hayne — 34.86°N, 78.03°WCastle Hayne — 34.80°N, 78.02°WCastle Hayne — 34.84°N, 77.55°WNdalithoni Limestone — 17.23°S, 178.95°EBarton Clay — 50.74°N, 1.69°WBarton Clay — 50.67°N, 1.57°WPawpaw — 32.73°N, 97.32°WPawpaw — 32.95°N, 97.32°WPawpaw — 32.84°N, 97.29°WPawpaw — 32.63°N, 97.40°WPawpaw — 32.86°N, 97.26°WPawpaw — 32.68°N, 97.24°WMaastricht — 50.86°N, 5.83°EMaastricht — 50.83°N, 5.68°EMaastricht — 50.84°N, 5.78°ESantee — 33.33°N, 79.67°WSantee — 33.35°N, 80.23°WSerraduy — 42.32°N, 0.54°ECayo Agua — 9.14°N, 82.01°WCayo Agua — 9.17°N, 82.04°WCayo Agua — 9.18°N, 82.05°WCayo Agua — 9.26°N, 82.05°WYorktown — 36.74°N, 76.60°WYorktown — 37.22°N, 76.64°WYorktown — 37.23°N, 76.96°WYorktown — 36.68°N, 77.10°WYorktown — 36.80°N, 76.59°WYorktown — 36.38°N, 77.06°WYorktown — 36.32°N, 76.73°WYorktown — 36.20°N, 76.75°WYorktown — 36.12°N, 76.74°WYorktown — 36.05°N, 76.72°WYorktown — 35.94°N, 77.56°WYorktown — 34.99°N, 76.85°W

Loading coastlines…

The named rock units Brachyura has been recovered from, largest first. Drawn where the rock is now, not where it formed. 615 further formations hold fewer occurrences each and are not listed. 2,319 occurrences have no formation on record, which is common for older literature.

Brachyura and its relatives

Eocene

Where Brachyura and its relatives were recorded in the Eocene.

Found in the same rock

3,419 taxa

The Paleobiology Database records at least 925 sites for Brachyura, and this reads 240 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

820 references

Each of the 5,471 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. 808 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 Brachyura

Credit
Biopics Dan Boone Honguyenseo Bernard Picton Biopics Philippe Boujon Splette Nosferattus Rushenb
Licence
CC BY-SA 4.0
Commercial use
the licence allows it

3D model

Source
Sketchfab
Licence
CC Attribution
Commercial use
cannot be read from the licence given — check the record

Smithsonian Open Access and MorphoSource were 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 itMeiura through timeFormations of the EoceneThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Latreille 1802