Heminautilus

Heminautilus
Temporal range: Aptian
~125–112 Ma
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Nautiloidea
Order: Nautilida
Family: †Cenoceratidae
Genus: †Heminautilus
Spath, 1927
Species
  • H. boselliorum
  • H. etheringtoni
  • H. japonicus
  • H. lallierianus
  • H. rangei
  • H. sanctaecrucis
  • H. saxbii
  • H. stantoni
  • H. tejeriensis
  • H. tyosiensis
  • H. verneuilli

Heminautilus is an extinct genus of nautiloids from the nautilacean family Cenoceratidae that lived during the Early Cretaceous. Fossils of Heminautilus have been registered in rocks of Barremian and Aptian age. Nautiloids are a subclass of shelled cephalopods that were once diverse and numerous but are now represented by only a handful of species.

Heminautilus has a discoidal compressed involute shell with flanks converging on a narrow flattened outer margin, the venter. Whorls are higher than they are wide. The suture is sinuous with a ventral lobe, subtriangular saddles on the ventral shoulders, broad lateral lobes, and narrow rounded saddles on the umbilical shoulders. The siphuncle is subcentral.

Species

The following species of Heminautilus have been described:

Distribution

Fossils of Heminautilus have been found in Bulgaria, Colombia (at Caballos Formation, Boyacá, Tolima and Une Formation), Egypt, France, Hungary, Japan, Mexico, Spain, Switzerland, Tunisia, the United Kingdom, the United States (Arkansas), Venezuela.

See also

References

  1. 1 2 Kummel, 1964
  2. 1 2 3 Heminautilus at Fossilworks.org
  3. ↑ Baudouin et al., 2016, p.87
  4. ↑ Baudouin, 2016, p.76
  5. ↑ Baudouin, 2016, p.66
  6. ↑ Baudouin, 2016, p.72

Bibliography

Further reading