Xystodesmidae
Xystodesmidae is a family of millipedes in the suborder Leptodesmidea within the order Polydesmida. The family Xystodesmidae was created by the American biologist Orator F. Cook in 1895 and named after the genus Xystodesmus. This family includes more than 390 known species distributed among 62 genera. Many species, however, remain undescribed: for example, it is estimated that the genus Nannaria contains over 200 species, but only 25 were described as of 2006. By 2022, 78 species in Nannaria have been described.

Bob Walker (uploaded by en:User:Paphrag ) · CC BY-SA 4.0 · 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
- XystodesmoideaPBDB
- Motility
- actively mobilePBDB, for Arthropoda
Time the record covers
At most 7.1 million years on record.
Every occurrence read is dated to somewhere between 23.04 Mya and 15.98 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.
2 occurrences of Xystodesmidae on record, most of them in the Miocene. The Paleobiology Database records this as a living group, and the chart stops with its fossils rather than at the present. 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- Miocene100%
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.
Xystodesmidae and its relatives
MioceneWhere Xystodesmidae and its relatives were recorded in the Miocene.
Found in the same rock
11 taxa- Polydesmida2 sites
- Stemmiulidae2 sites
- Dendryphantini1 site
- Diplopoda1 site
- Juliformia1 site
- Neomachilellus (Praeneomachilellus) ezetaelenensis1 site
- Platyrhacidae1 site
- Polycricus1 site
- Salticinae1 site
- Siphonophora1 site
- Spirobolida1 site
The Paleobiology Database records 2 sites for Xystodesmidae, 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
1 referenceEach 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 doi.org. Relayed as the Paleobiology Database holds them, not checked against what they resolve to.
Media and terms
Media content1
Picture of Xystodesmidae
- Source
- Wikipedia/Commons
- Credit
- Bob Walker (uploaded by en:User:Paphrag )
- Licence
- CC BY-SA 4.0
- Commercial use
- the licence allows it
No 3D scan of Xystodesmidae 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 itXystodesmoidea through timeFormations of the MioceneThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. Cook 1895