Enchytraeidae

Enchytraeidae is a family of microdrile oligochaetes. They resemble small earthworms and include both terrestrial species known as potworms that live in highly organic terrestrial environments, as well as some that are marine. More than 700 species in about 30 genera have been described worldwide, although the true diversity of the family is thought to be much higher. Most species are small, whitish or transparent worms only a few millimetres long that feed on decaying organic matter and the microorganisms colonizing it, making them important contributors to decomposition and nutrient cycling in soils. The peculiar genus Mesenchytraeus is known as "ice worms", as they spend the majority of their lives within glaciers, only rising to the surface at certain points in the summer. Enchytraeidae also includes the Grindal worm, which is commercially bred as aquarium fish food. Certain varieties of Enchytraeidae are partially responsible for the notorious "dark earth" archaeological layers in post-Roman Era British urban centers such as London.

Enchytraeidae

Paul Bachhausen · CC BY-SA 3.0 de · 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
OligochaetaPBDB

Time the record covers

At most 3.9 million years on record.

The one occurrence read is dated to somewhere between 37.71 Mya and 33.9 Mya, which is a dating window rather than a span.

Eocene — about 1 of 1 occurrenceEoceneOligocene — about 0 of 1 occurrence38–38 Mya — about 0.0 occurrences38–37 Mya — about 0.0 occurrences37–37 Mya — about 0.0 occurrences37–37 Mya — about 0.0 occurrences37–37 Mya — about 0.0 occurrences37–37 Mya — about 0.0 occurrences37–37 Mya — about 0.0 occurrences37–36 Mya — about 0.0 occurrences36–36 Mya — about 0.0 occurrences36–36 Mya — about 0.0 occurrences36–36 Mya — about 0.0 occurrences36–36 Mya — about 0.0 occurrences36–36 Mya — about 0.0 occurrences36–35 Mya — about 0.0 occurrences35–35 Mya — about 0.0 occurrences35–35 Mya — about 0.0 occurrences35–35 Mya — about 0.0 occurrences35–35 Mya — about 0.0 occurrences35–35 Mya — about 0.0 occurrences35–35 Mya — about 0.0 occurrences35–34 Mya — about 0.0 occurrences34–34 Mya — about 0.0 occurrences34–34 Mya — about 0.0 occurrences34–34 Mya — about 0.0 occurrences38.21 Mya33.4 Mya

1 occurrence of Enchytraeidae on record, most of them in the Eocene. 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

1 occurrences

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.

Enchytraeidae and its relatives

Eocene

Where Enchytraeidae and its relatives were recorded in the Eocene.

Found in the same rock

6 taxa

The Paleobiology Database records 1 site for Enchytraeidae, 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 reference

Each of the 1 occurrence 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 the Paleobiology Database's own record for the work.

Media and terms

Media content1

Picture of Enchytraeidae

Credit
Paul Bachhausen
Licence
CC BY-SA 3.0 de
Commercial use
the licence allows it

No 3D scan of Enchytraeidae 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 itOligochaeta through timeFormations of the EoceneThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Vejdovsky 1879