Hakuluettelo:
Käännös:
Hettangian (suomeksi)
- Määritelmät:
- (lb, en, geology, paleontology) The earliest age of the Jurassic period, from 199.3–201.3Ma
- The corresponding lowest stage of the Jurassic system, marked by the lowest strata in which the neoammonite genus (taxlink, Psiloceras, genus, noshow=1) appears.