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Related to ammonoid: ammonite, Ammonoidea


An extinct cephalopod mollusk of the subclass Ammonoidea of the Devonian to Cretaceous Periods, having a straight or coiled chambered shell characterized by more or less intricate suture patterns where the septa between individual chambers join the outer shell wall.


any of the extinct group of sea-dwelling cephalopod molluscs with coiled and chambered shells


(ˈæm əˌnɔɪd)

ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.ammonoid - one of the coiled chambered fossil shells of extinct mollusksammonoid - one of the coiled chambered fossil shells of extinct mollusks
fossil - the remains (or an impression) of a plant or animal that existed in a past geological age and that has been excavated from the soil
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Furnish and Glenister (1970) described the Permian ammonoid Cyclolobus from the Salt Range.
Through the climatic changes, conodont and ammonoid faunae were initially able to recover very quickly during the Early Triassic as unusually short-lived species emerged.
It is difficult to compare these ammonoid assemblages with the European standards because of the absence of respective data.
A new prodromitid ammonoid genus from the Hannibal Shale (Lower Mississippian) of Missouri.
The minimum test was used by Jablonski (1987, 1994) to test Cope's Rule among Cretaceous molluscs and by Boyajian and Lutz (1992) to analyze the evolution of sutural complexity in ammonoid cephalopods.
Emergence and collapse of the Frasnian conodont and ammonoid communities in the Holy Cross Mountains, Poland.
However, the problem associated with the identification of the Jurassic - Cretaceous boundary persists for shallow water marine and continental sedimentary successions in which biostratigraphic data are derived from several groups of benthic macrofossils, foraminifera, ostracods and charophytes that are uncorrelated to ammonoid or planktonic zonations.
This particular ammonoid is from the SouthPark Mall in Charlotte, North Carolina.
For several more years, Tim, focusing increasingly on the marine Triassic and its ammonoid fauna, divided his field time between the Arctic Islands and northeastern British Columbia, where the upper part of the Triassic stratigraphic column is particularly well developed.
(2014) review the stratigraphic distribution of the Hauterivian-Albian ammonoid species in the Maestrat Basin (E Spain), providing an updated and comprehensive biostratigraphic framework as a reference for the analysis of the Lower Cretaceous strata of the Maestrat Basin.