Bathysoma lutkeni is an extinct lamprid from the Danian

Danian

The Danian is the oldest age or lowermost stage of the Paleocene epoch or series, the Paleogene period or system and the Cenozoic era or erathem. The beginning of the Danian age is at the Cretaceous-Tertiary extinction event...

 epoch of Sweden

Sweden

Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....

, and is the second oldest lamprid known, after Nardovelifer

Nardovelifer

Nardovelifer altipinnis is the oldest known lamprid fish. It dates from the Campanian epoch of Nardò, Italy....

 of Campanian

Campanian

The Campanian is, in the ICS' geologic timescale, the fifth of six ages of the Late Cretaceous epoch . The Campanian spans the time from 83.5 ± 0.7 Ma to 70.6 ± 0.6 Ma ...

/Maastrichian Italy

Italy

Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

. B. lutkeni has a disk-shaped body and an elongated head. It was originally described as a menid

Mene

The moonfish of the genus Mene , the sole extant genus of the family Menidae are disk-shaped fish which bear a vague resemblance to gourami, thanks to their thread-like pelvic fins...

 bony fish. Later, it was described as being a basal snake mackerel

Snake mackerel

Gempylidae is a family of perciform fishes, commonly known as snake mackerels or escolars.They are elongate fishes with a similar appearance to barracudas, having a long dorsal fin, usually with one or finlets trailing it. The largest species, including the snoek, Thyrsites atun, grow up to two...

. Eventually, anatomical similarities with the Turkmenids

Turkmenidae

Turkmenidae is an extinct family of lamprids from the Paleogene of Turkmenistan. They were small, disk-shaped fish that bore a strong resemblance to their closest living relatives, the opahs....

 were noted, and B. lutkeni is now regarded as an extremely basal lamprid.

External links

• Bathysoma at the Paleobiology Database
  Paleobiology Database
  ' is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms.-History:The Paleobiology Database was founded in 2000. It has been funded by the National Science Foundation and the Australian Research Council...
  
  
• Lampridiformes