Petalichthyida

Petalichthyida is an extinct order of small, flattened placoderm fish. They are typified by their splayed pectoral fins, exaggerated lateral spines, flattened bodies, and numerous tubercles that decorated all of the plates and scales of their armor. They reached a peak in diversity during the Early Devonian and were found throughout the world, particularly in Europe, North America, Asia, South America, and Australia. The petalichthids Lunaspis and Wijdeaspis are among the best known. The earliest and most primitive known petalichthyid is Diandongpetalichthys, which is from earliest Devonian-aged strata of Yunnan. The presence of Diandongpetalichthys, along with other primitive petalichthyids including Neopetalichthys and Quasipetalichthys, and more advanced petalichthyids, suggest that the order may have arisen in China, possibly during the late Silurian.

Petalichthyida

Ghedoghedo · Public Domain · 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
PlacodermiPBDB
Diet
carnivorePBDB, for Placodermi
Life habit
nektonicPBDB, for Placodermi
Motility
actively mobilePBDB, for Placodermi

Time the record covers

At least 6.6 million years on record.

The record covers at least 419.62 Mya to 413.02 Mya. No occurrence read is dated outside 422.7 Mya to 410.62 Mya.

Silurian — about 1 of 2 occurrencesSilurianDevonian — about 1 of 2 occurrencesDevonian423–422 Mya — about 0.1 occurrences422–422 Mya — about 0.1 occurrences422–421 Mya — about 0.1 occurrences421–421 Mya — about 0.1 occurrences421–421 Mya — about 0.1 occurrences421–420 Mya — about 0.1 occurrences420–420 Mya — about 0.1 occurrences420–419 Mya — about 0.0 occurrences413–413 Mya — about 0.1 occurrences413–412 Mya — about 0.2 occurrences412–412 Mya — about 0.2 occurrences412–411 Mya — about 0.2 occurrences411–411 Mya — about 0.2 occurrences411–411 Mya — about 0.2 occurrences419.62 Mya413.02 Mya423.2 Mya410.1 Mya

2 occurrences of Petalichthyida on record. 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

2 formations

Yulongsi — 25.45°N, 103.77°EPosongchong — 27.40°N, 103.80°E

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

Found in the same rock

13 taxa

The Paleobiology Database records 1 site for Petalichthyida, 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. Each entry links to the Paleobiology Database's own record for the work.

Media and terms

Media content1

Picture of Petalichthyida

Credit
Ghedoghedo
Licence
Public Domain
Commercial use
the licence allows it

No 3D scan of Petalichthyida was found in MorphoSource and Sketchfab.

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 itPlacodermi through timeThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0.