Gypsonictops
Gypsonictops is an extinct genus of leptictidan mammals of the family Gypsonictopidae, which was described in 1927 by George Gaylord Simpson. Species in this genus were small mammals and the first representatives of the order Leptictida, that appeared during the Upper Cretaceous.

George Gaylord Simpson · 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
- GypsonictopidaePBDB
- Diet
- omnivore, frugivorePBDB
- Life habit
- ground dwellingPBDB, for Gypsonictopidae
- Motility
- actively mobilePBDB, for Osteichthyes
- Environment
- terrestrialPBDB, for Eutheria
Time the record covers
At most 18 million years on record.
Every occurrence read is dated to somewhere between 83.6 Mya and 66 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.
94 occurrences of Gypsonictops on record, most of them in the Late Cretaceous. 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
94 occurrences- Late Cretaceous100%
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
16 formations
- Hell Creek Formation · Montana Group35
- Lance Formation22
- Scollard Formation · Edmonton Group6
- Judith River Formation · Montana Group5
- Oldman Formation · Belly River Group4
- Kaiparowits Formation4
Loading coastlines…
The named rock units Gypsonictops has been recovered from, largest first. Drawn where the rock is now, not where it formed. 4 occurrences have no formation on record, which is common for older literature.
Gypsonictops and its relatives
Late CretaceousWhere Gypsonictops and its relatives were recorded in the Late Cretaceous.
Found in the same rock
479 taxa- Meniscoessus robustus45 sites
- Cimolodon nitidus41 sites
- Didelphodon vorax35 sites
- Mesodma thompsoni32 sites
- Pediomys elegans29 sites
- Myledaphus bipartitus28 sites
- Protolambda hatcheri28 sites
- Lepisosteus occidentalis27 sites
- Scapherpeton tectum24 sites
- Trionychidae24 sites
- Cimolomys gracilis22 sites
- Protolambda florencae22 sites
- Brachychampsa montana21 sites
- Theropoda21 sites
- Alphadon marshi20 sites
- Lonchidion selachos20 sites
- Paronychodon20 sites
- Borealosuchus sternbergii19 sites
- Habrosaurus dilatus19 sites
- Mesodma formosa19 sites
- Opisthotriton kayi19 sites
- Alphadon18 sites
- Chamops segnis18 sites
- Mesodma18 sites
The Paleobiology Database records 86 sites for Gypsonictops, 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
35 references- Fossil mammals of the type Lance Formation, Wyoming. Part III. Eutheria and summary18
- The Bug Creek problem and the Cretaceous-Tertiary transition at McGuire Creek, Montana12
- A study of Mammalia and geology across the Cretaceous-Tertiary boundary in Garfield County, Montana7
- Latest Cretaceous mammals of upper part of Edmonton Formation of Alberta, Canada, and review of marsupial-placental dichotomy in mammalian evolution5
- Mammals from the end of the age of dinosaurs in North Dakota and southeastern Montana, with a reappraisal of geographic differentiation among Lancian mammals3
- The therian mammalian fauna (Campanian) of Quarry 1, Fossil Forest study area, San Juan Basin, New Mexico3
- Fossil mammals from the "Mesaverde" Formation (Late Cretaceous, Judithian) of the Bighorn and Wind River basins, Wyoming, with definitions of Late Cretaceous North American Land-Mammal "Ages"3
- Mammal evolution near the Cretaceous-Tertiary Boundary3
- Late Cretaceous mammals of western South Dakota, 19743
- Mammals from the Upper Cretaceous Oldman Formation, Alberta. III. Eutheria3
- Fossil Vertebrate Collections2
- Blob, 19922
Each of the 94 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. 23 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 content1
Picture of Gypsonictops
- Source
- Wikipedia/Commons
- Credit
- George Gaylord Simpson
- Licence
- Public Domain
- Commercial use
- the licence allows it
No 3D scan of Gypsonictops 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 itGypsonictopidae through timeFormations of the Late CretaceousThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. Simpson 1927