Zemistephanus

Zemistephanus is an extinct ammonite genus from the middle Jurassic of western North America and Western Australia, named by McLearn 1927. Zemistephanus is included in the stephanoceratoid family Otoitidae, which are characterized by shells that begin as barrel-shaped cadicones but which become planulate later in life. Body chambers are reduced in size and are excentric. Similar genera are Pseudotoites and Emileia

No picture of Zemistephanus was found. Wikipedia, Wikidata and iDigBio were searched and had none. Smithsonian Open Access did not answer, so this is what the others held rather than everything there is. GBIF was asked, and what came back is not recorded: nothing, or a picture this site could not tie to Zemistephanus, or no answer at all. This entry cannot say which.

On record

Recorded, not inferred
Sits inside
OtoitidaePBDB
Diet
carnivorePBDB, for Ammonoidea
Life habit
nektonicPBDB, for Ammonoidea
Motility
fast-movingPBDB, for Ammonoidea
Vision
well-developedPBDB, for Cephalopoda
Environment
marinePBDB, for Cephalopoda

Time the record covers

At most 2.7 million years on record.

Every occurrence read is dated to somewhere between 170.9 Mya and 168.2 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.

Middle Jurassic — about 5 of 5 occurrencesMiddle Jurassic171–171 Mya — about 0.2 occurrences171–171 Mya — about 0.3 occurrences171–171 Mya — about 0.3 occurrences171–170 Mya — about 0.3 occurrences170–170 Mya — about 0.3 occurrences170–170 Mya — about 0.3 occurrences170–170 Mya — about 0.3 occurrences170–170 Mya — about 0.3 occurrences170–170 Mya — about 0.3 occurrences170–170 Mya — about 0.3 occurrences170–170 Mya — about 0.3 occurrences170–169 Mya — about 0.3 occurrences169–169 Mya — about 0.3 occurrences169–169 Mya — about 0.3 occurrences169–169 Mya — about 0.3 occurrences169–169 Mya — about 0.3 occurrences169–169 Mya — about 0.3 occurrences169–169 Mya — about 0.3 occurrences169–169 Mya — about 0.2 occurrences169–168 Mya — about 0.0 occurrences168–168 Mya — about 0.0 occurrences168–168 Mya — about 0.0 occurrences171.4 Mya167.7 Mya

5 occurrences of Zemistephanus on record, most of them in the Middle Jurassic. 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 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

Newmarracarra Limestone — 28.79°S, 114.80°ESnowshoe — 44.13°N, 118.98°W

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

Zemistephanus and its relatives

Middle Jurassic

Where Zemistephanus and its relatives were recorded in the Middle Jurassic.

Found in the same rock

18 taxa

The Paleobiology Database records 5 sites for Zemistephanus, 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 5 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

3D model

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

No picture of Zemistephanus was found. Wikipedia, Wikidata and iDigBio were searched and had none.

Smithsonian Open Access did not answer, so this is what the others held rather than everything there is.

GBIF was asked, and what came back is not recorded: nothing, or a picture this site could not tie to Zemistephanus, or no answer at all. This entry cannot say which.

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 itOtoitidae through timeFormations of the Middle JurassicThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0.