Trachypachidae
The Trachypachidae are a family of beetles that generally resemble small ground beetles, but that are distinguished by the large coxae of their rearmost legs. There are only six known extant species in the family, with four species of Trachypachus found in northern Eurasia and northern North America, and two species of Systolosoma in Chile and Argentina. They were originally more diverse, with dozens of species described in the Mesozoic.

Yves Bousquet · CC BY 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- Also called
- false ground beetlePBDB
- Sits inside
- AdephagaPBDB
- Motility
- actively mobilePBDB, for Arthropoda
- Environment
- terrestrialPBDB, for Insecta
Time the record covers
At least 250 million years on record.
The record covers at least 251.1 Mya to 129 ka. No occurrence read is dated outside 251.902 Mya to 11.7 ka.
105 occurrences of Trachypachidae on record, most of them in the Late Jurassic. 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
105 occurrences- Early Triassic4%
- Middle Triassicunder 1%
- Late Triassic11%
- Early Jurassic20%
- Middle Jurassic2%
- Late Jurassic33%
- Early Cretaceous22%
- Miocene3%
- Plioceneunder 1%
- Pleistocene3%
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
31 formations
- Posidonia Shale Formation17
- Karabastau Formation14
- Glushkovo Formation12
- Blackstone Formation · Ipswich Coal Measures Group8
- Gurvan-Eren Formation5
- Maltsevo Formation4
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The named rock units Trachypachidae has been recovered from, largest first. Drawn where the rock is now, not where it formed. 7 further formations hold fewer occurrences each and are not listed. 7 occurrences have no formation on record, which is common for older literature.
Trachypachidae and its relatives
Late JurassicWhere Trachypachidae and its relatives were recorded in the Late Jurassic.
Found in the same rock
3,165 taxa- Ampliceps furcitibia8 sites
- Oxycorynoides (Oxycorynoides) similis8 sites
- Protoscelis jurassica8 sites
- Aktassoblatta fusca7 sites
- Ano ona7 sites
- Archirhyphus asiaticus7 sites
- Asioblatta punctata7 sites
- Asvab bavsa7 sites
- Blattula brevicaudata7 sites
- Blattula microscopica7 sites
- Blattula rectinervosa7 sites
- Decomposita triocella7 sites
- Falcatusiblatta casovec7 sites
- Latiblatta lativalvata7 sites
- Liassothrips crassipes7 sites
- Memento mori7 sites
- Olzmasg zi7 sites
- Protoscelis longicornis7 sites
- Rhipidoblatta fusca7 sites
- Rhipidoblatta matriky7 sites
- Akinisia chorevei6 sites
- Ampliceps dubius6 sites
- Anaxyelidae6 sites
- Cameloblatta variegata6 sites
The Paleobiology Database records 66 sites for Trachypachidae, 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
28 references- Mezozoiskie zhestkokryiye29
- Die Insektenfauna des Ostniedersachsischen Oberen Lias17
- Beetles, Scarabaeida, in Pozdne-Mezozoyskie Nasekomye Vostochnogo Zabaykal'ya7
- Late Cenozoic insects of northern Eurasia5
- New Jurassic and Cretaceous ground beetles (Insecta, Coleoptera, Caraboidea) from Asia5
- Beetles. Scarabaeida (=Coleoptera), in Nasekomye v rannemelovykh ekosistemakh zapadnoy Mongolii5
- Mesozoic Trachypachidae (Insecta: Coleoptera) from China4
- Mesozoic insects of Queensland Part I - introduction and Coleoptera4
- Descriptions of the fossil Insects; Mesozoic and Tertiary Insects of Queensland and New South Wales. Descriptions of the fossil Insects and stratigraphical features4
- Ademosynoides asiaticus Martynov, 1936, the earliest known member of an extant beetle family (Insecta, Coleoptera, Trachypachidae)3
- Zhestkokrylye iz Yury Sibiri i zapadnoy Mongolii3
- Cretaceous beetles from Jinju Formation: Trachypachidae (Coleoptera: Adephaga)2
Each of the 105 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. 16 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 Trachypachidae
- Source
- Wikipedia/Commons
- Credit
- Yves Bousquet
- Licence
- CC BY 3.0
- Commercial use
- the licence allows it
No 3D scan of Trachypachidae was found in Smithsonian Open Access and Sketchfab.
MorphoSource 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 itAdephaga through timeFormations of the Late JurassicThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. Thomson 1857