Achatella
Achatella is a genus of trilobite in the order Phacopida, which existed in what is now Ontario, Canada. It was named by Delo in 1935, and the type species is Achatella achates, which was originally assigned to the genus Dalmanites by Billings in 1860. Achatella also contains the species Achatella billingsi, and Achatella truncatocaudata.

Notafly · CC BY-SA 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- Sits inside
- PterygometopinaePBDB
- Diet
- carnivorePBDB, for Phacopina
- Life habit
- low-level epifaunalPBDB, for Trilobita
- Motility
- fast-movingPBDB, for Trilobita
- Vision
- well-developedPBDB, for Pterygometopidae
- Environment
- marinePBDB, for Trilobita
Time the record covers
At least 13 million years on record.
The record covers at least 458.2 Mya to 445.2 Mya. No occurrence read is dated outside 471.3 Mya to 443.1 Mya.
38 occurrences of Achatella on record, most of them in the Ordovician. 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
38 occurrences- Ordovician100%
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
23 formations
- Verulam Formation · Simcoe Group4
- Kope Formation3
- Fairview Formation2
- Grande Coupe Formation2
- Bobcaygeon Formation · Simcoe Group2
- Knockerk Formation2
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The named rock units Achatella has been recovered from, largest first. Drawn where the rock is now, not where it formed.
Achatella and its relatives
OrdovicianWhere Achatella and its relatives were recorded in the Ordovician.
Found in the same rock
639 taxa- Conularia11 sites
- Isotelus10 sites
- Rafinesquina10 sites
- Escharopora9 sites
- Isotelus gigas9 sites
- Modiolopsis8 sites
- Trematis8 sites
- Ambonychia7 sites
- Calyptaulax callicephalus7 sites
- Ctenodonta7 sites
- Flexicalymene7 sites
- Hallopora7 sites
- Homotrypa7 sites
- Lophospira7 sites
- Mesopalaeaster7 sites
- Nuculites7 sites
- Petrocrania7 sites
- Platystrophia7 sites
- Pterinea7 sites
- Zygospira7 sites
- Arthropoma6 sites
- Ceramoporella6 sites
- Ceratocephala6 sites
- Ceraurus6 sites
The Paleobiology Database records 35 sites for Achatella, 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
17 references- Palaeozoic geology of the Lake Simcoe Area, Ontario6
- The fossil fauna of the Ordovician in the Cincinnati Region6
- Pterygometopine Trilobites from the Ordovician of Baltoscandia4
- Trilobites of the Pabos Formation (Ashgillian, Upper Ordovician), Percé area, Quebec3
- Trilobite Biostratigraphy in the Middle and Upper Ordovician of Western Leningrad Region2
- Analysis of sample-level properties along a paleoenvironmental gradient: the behavior of evenness as a function of sample size2
- The Walcott-Rust Quarry: Middle Ordovician Trilobite Konservat-Lagerstätten2
- Early Caradoc Trilobites of Eastern Ireland and their paleogeographical significance2
- The uppermost Ordovician (Hirnantian) trilobites of Girvan, SW Scotland with a review of coeval trilobite faunas2
- The fauna of the Kimmswick limestone of Missouri and Illinois2
- Available generic names for trilobites1
- Stratigraphy of the Ordovician of the Lac Saint-Jean and Chicoutimi outliers, Quebec1
Each of the 38 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. 5 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 Achatella
- Source
- Wikipedia/Commons
- Credit
- Notafly
- Licence
- CC BY-SA 3.0
- Commercial use
- the licence allows it
No 3D scan was found. Smithsonian Open Access, MorphoSource and Sketchfab were all searched.
The description on this site
- Source
- Wikipedia, “Achatella”
- 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 itPterygometopinae through timeFormations of the OrdovicianThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. Delo 1935