Tetragonias njalilus

Tetragonias is an extinct genus of dicynodont from the Anisian Manda Beds of Tanzania. With tetra meaning "four," and goni meaning "angle," the name references the square shape of the Tetragonias skull when viewed dorsally. Not to be confused with the plant Tetragonia, Tetragonias were dicynodont anomodonts discovered in the late 1960s by paleontologist A. R. I. Cruickshank in the Manda Formation. Only the type species, T. njalilus, has been recognized.

Tetragonias njalilus

H. Zell · CC BY-SA 3.0 · 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
TetragoniasPBDB
Diet
herbivorePBDB, for Dicynodontia
Motility
actively mobilePBDB, for Osteichthyes
Environment
terrestrialPBDB, for Amniota

Time the record covers

At most 5.6 million years on record.

Every occurrence read is dated to somewhere between 247 Mya and 241.464 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.

Early Triassic — about 0 of 2 occurrencesMiddle Triassic — about 2 of 2 occurrencesMiddle Triassic247–247 Mya — about 0.1 occurrences247–247 Mya — about 0.1 occurrences247–246 Mya — about 0.1 occurrences246–246 Mya — about 0.1 occurrences246–246 Mya — about 0.1 occurrences246–246 Mya — about 0.1 occurrences246–246 Mya — about 0.1 occurrences246–245 Mya — about 0.1 occurrences245–245 Mya — about 0.1 occurrences245–245 Mya — about 0.1 occurrences245–245 Mya — about 0.1 occurrences245–244 Mya — about 0.1 occurrences244–244 Mya — about 0.1 occurrences244–244 Mya — about 0.1 occurrences244–244 Mya — about 0.1 occurrences244–244 Mya — about 0.1 occurrences244–243 Mya — about 0.1 occurrences243–243 Mya — about 0.1 occurrences243–243 Mya — about 0.1 occurrences243–243 Mya — about 0.1 occurrences243–242 Mya — about 0.1 occurrences242–242 Mya — about 0.1 occurrences242–242 Mya — about 0.1 occurrences242–242 Mya — about 0.1 occurrences242–242 Mya — about 0.1 occurrences242–241 Mya — about 0.1 occurrences247.5 Mya241 Mya

2 occurrences of Tetragonias njalilus on record, most of them in the Middle Triassic. 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

2 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

1 formation

Manda Beds — 10.33°S, 35.25°E

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

Tetragonias njalilus and its relatives

Middle Triassic

Where Tetragonias njalilus and its relatives were recorded in the Middle Triassic.

Found in the same rock

3 taxa

The Paleobiology Database records 2 sites for Tetragonias njalilus, and this reads all of them. The number is how many of those sites it was catalogued from too.

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

2 references

Each of the 2 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 content1

Picture of Tetragonias njalilus

Credit
H. Zell
Licence
CC BY-SA 3.0
Commercial use
the licence allows it

No 3D scan of Tetragonias njalilus was found in Sketchfab.

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 itTetragonias through timeFormations of the Middle TriassicThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. (von Huene 1942)