Atactodea
Atactodea is a genus of saltwater clams of the family Mesodesmatidae described by William Healey Dall in 1895.

Marie HENNION · CC BY 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
- MesodesmatinaePBDB
- Diet
- suspension feederPBDB, for Mactroidea
- Life habit
- infaunalPBDB, for Mactroidea
- Motility
- facultatively mobilePBDB, for Mactroidea
- Vision
- blindPBDB, for Bivalvia
Time the record covers
At most 2.6 million years on record.
Every occurrence read is dated to somewhere between 2.58 Mya and 11.7 ka, and nothing in the dating separates them, so that window is what the record shows rather than a span.
4 occurrences of Atactodea on record, most of them in the Pleistocene. 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
4 occurrences- Pleistocene100%
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
1 formation
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The named rock units Atactodea has been recovered from, largest first. Drawn where the rock is now, not where it formed. 3 occurrences have no formation on record, which is common for older literature.
Atactodea and its relatives
PleistoceneWhere Atactodea and its relatives were recorded in the Pleistocene.
Found in the same rock
192 taxa- Acmaea2 sites
- Amoria2 sites
- Brachidontes ustulatus2 sites
- Callista2 sites
- Fragum2 sites
- Fragum unedo2 sites
- Gouldia (Gouldia)2 sites
- Monodonta labio2 sites
- Placamen2 sites
- Tectus fenestratus2 sites
- Tectus pyramis2 sites
- Thalotia2 sites
- Acmaeidae1 site
- Acrosterigma1 site
- Acrosterigma (Vasticardium)1 site
- Actaeopyramis1 site
- Acteocina1 site
- Adamnestia1 site
- Alvenius ojianus1 site
- Anachis (Zafra)1 site
- Anadara (Mabellarca)1 site
- Anadara (Tegillarca) granosa1 site
- Anisodonta1 site
- Anodontia1 site
The Paleobiology Database records 3 sites for Atactodea, 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
3 references- Cenozoic Molluscs and Echinoids of Barrow Island, Western Australia2
- Pleistocene Coral Reef Terraces on the Saudi Arabian Side of the Gulf of Aqaba, Red Sea1
- Pleistocene molluscan fauna of the Sakishima Formation, Shima Peninsula, central Japan1
Each of the 4 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
Picture of Atactodea
- Source
- Wikipedia/Commons
- Credit
- Marie HENNION
- Licence
- CC BY 4.0
- Commercial use
- the licence allows it
No 3D scan of Atactodea 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
- Source
- Wikipedia, “Atactodea”
- 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 itMesodesmatinae through timeFormations of the PleistoceneThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. (Dall 1895)