Elmidae

Elmidae, commonly known as riffle beetles, is a family of beetles in the superfamily Byrrhoidea described by John Curtis in 1830. Both adults and larvae are usually aquatic, living under rocks in fast-flowing shallow areas of streams, such as riffles, feeding on algae and biofilms. There are more than 150 genera and 1,500 described species in Elmidae. The oldest record of the group is Cretohypsilara from the Cenomanian aged Burmese amber.

Elmidae

Hendrik Freitag · 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
riffle beetlePBDB
Sits inside
DryopoideaPBDB
Motility
actively mobilePBDB, for Arthropoda
Environment
terrestrialPBDB, for Insecta

Time the record covers

At least 93 million years on record.

The record covers at least 93.9 Mya to 129 ka. No occurrence read is dated outside 100.5 Mya to 11.7 ka.

Early Cretaceous — about 0 of 102 occurrencesLate Cretaceous — about 1 of 102 occurrencesLate CretaceousPaleocene — about 0 of 102 occurrencesEocene — about 3 of 102 occurrencesEoceneOligocene — about 1 of 102 occurrencesOligoceneMiocene — about 0 of 102 occurrencesPliocene — about 0 of 102 occurrencesPleistocene — about 97 of 102 occurrences103–99 Mya — about 0.2 occurrences99–96 Mya — about 0.5 occurrences96–92 Mya — about 0.3 occurrences58–55 Mya — about 0.2 occurrences55–51 Mya — about 0.4 occurrences51–48 Mya — about 0.4 occurrences41–38 Mya — about 0.1 occurrences38–34 Mya — about 2 occurrences34–31 Mya — about 0.1 occurrences27–24 Mya — about 0.8 occurrences24–21 Mya — about 0.2 occurrences3.4–0 Mya — about 97 occurrences93.9 Mya129 ka103 Mya0 Mya

102 occurrences of Elmidae on record, most of them in the Pleistocene. 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

102 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.

Found in

5 formations

Highbury Silts and Sands — 51.56°N, 0.06°WOlympia beds — 47.66°N, 122.43°WRott — 50.75°N, 7.26°EYoshino — 32.83°N, 130.64°EPalana — 27.87°N, 72.87°E

Loading coastlines…

The named rock units Elmidae has been recovered from, largest first. Drawn where the rock is now, not where it formed. 36 occurrences have no formation on record, which is common for older literature.

Elmidae and its relatives

Pleistocene

Where Elmidae and its relatives were recorded in the Pleistocene.

Found in the same rock

2,011 taxa

The Paleobiology Database records 32 sites for Elmidae, 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

10 references

Each of the 102 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 Elmidae

Credit
Hendrik Freitag
Licence
CC BY 3.0
Commercial use
the licence allows it

No 3D scan of Elmidae 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 itDryopoidea through timeFormations of the PleistoceneThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Curtis 1830