白羊石(學名:Arietites),又名白羊菊石、單脊菊石,是生存在早侏羅世海洋中的一屬菊石。其化石在德國、意大利、英國、加拿大和中國等地都有發現。[2]
特徵
白羊石的殼體為平旋捲式,形似大羊角;外殼的橫截面近似於方形,殼表有明顯的粗橫肋條,殼腹呈鈍圓狀而突出,其上有三條縱脊與二個凹溝。[3]
和本屬近似的屬為龍骨較少的Megarietites屬和肋條間距更緊密的Epammonites屬。
物種[2]
- Arietites bonnardii
- Arietites geometricus
- Arietites longicellus
- Arietites semicostatus
- Arietites wichmanni
參考文獻
延伸閱讀
Wikiwand in your browser!
Seamless Wikipedia browsing. On steroids.
Every time you click a link to Wikipedia, Wiktionary or Wikiquote in your browser's search results, it will show the modern Wikiwand interface.
Wikiwand extension is a five stars, simple, with minimum permission required to keep your browsing private, safe and transparent.