ammonoid|ammonoids in English

noun

extinct cephalopod mollusk

Use "ammonoid|ammonoids" in a sentence

1. Abundant Concretions at several levels contain well-preserved ammonoids, bivalves and occasional fish

2. Additional research has shown that subsequent to this elimination of ammonoids from the global biota, nautiloids began an evolutionary radiation into shell shapes and complexities theretofore known only from ammonoids.

3. Comparison of eggs and brood care between Argonautids and ammonoids shows the following

4. Some of the more exotic marine life included the now extinct trilobites and ammonoids.

5. Other species have squat whorls, the whole ammonoid being so tightly rolled up as to be almost spherical.

6. Many of the ammonoids lived within large, coiled chambered shells resembling those of the present-day nautilus.

7. The most remarkable features, however, are preserved organic sheets in the ammonoid phragmocones which are normally readily destroyed.

8. 8 Other species have squat whorls, the whole ammonoid being so tightly rolled up as to be almost spherical.

9. The study leads to the conclusion that the Hangenberg Event caused an almost complete change in the morphospace adopted by ammonoids.

10. With the aid of new finds of anomalous ammonoids from the Franconian Jura, the phenomenon of the “Rippensdieitelung” is again discussed.

11. The differences in morphological plasticity are interpreted in terms of the function of the ammonoid conch, especially the orientation of the aperture during life.

12. Reef-dwelling organisms are represented by pelecypods, gastropods, rare small ammonoids, brachiopods, ostracods (especially in reef-cavities), crinoids, echinoids, serpulids and crustaceans (exclusively fecal pellets).

13. On the other hand an analysis of current phylogenetic connections of certain ammonoid groups demonstrates that they give no clue for tracing homologies.

14. The jaw apparati of Paleozoic and Triassic ammonoids are simìlar in shape to parrots’ beaks; they possess sharp cutting-edges and consist of chitinous material.

15. The anti-Darwinian “Typostrophe Theory” of O.H.Schindewolf can be put to the test by revisiting the ammonoid examples on which this macroevolutionary model was founded.

16. Ontogenetic analysis of chamber length, total suture length and lateral saddle dimensions of an Ammonoid shell reveal a possible new system requiring relatively little genetic information.

17. From 20 sections in the Tafilalt (eastern Anti-Atlas, Morocco), 13 early Emsian ammonoid species of the families Mimosphinctidae, Mimoceratidae, Teicherticeratidae, Mimagoniatitidae, and Auguritidae have been discovered.

18. Constructional and morphological analysis of ammonoid shells provides new and calculable features. In addition, it leads to a better understanding of a given form and its origin.

19. New finds of fossils including bivalves, ammonoids, brachiopods and palynomorphs from the Middle Triassic Reifling Formation significantly improve the age assignment for this unit in Liechtenstein and Vorarlberg.

20. The new ammonoid speciesDesmoceras (Pseudouhligella) intrapunctatum (DesmoceratoideaZittel, 1895) is described and figured from the dark glauconitic marls of the Lower Albian of Ambatolafia (Mahajanga Basin of northwestern Madagascar).

21. The body chamber of an ammonoid of the genus Calliphylloceras (Suborder Phylloceratina) containing its lower jaw is reported from the Upper Bajocian (Strenoceras niortense Zone) of the Northern Caucasus.

22. A small piece, sectioned for investigation by scanning electron microscope, proved the existence of a slightly altered layer of mother of pearl, comparable with those of the ammonoid and nautiloid shells.

23. Tubes seem to have fossilized due to microbially mediated phosphatization that could be favoured by a set of parameters which operated rather at the scale of ammonoid carcasses: closed, poorly oxygenated conditions, and reduced pH.

24. All clymenüds as well as tornoceratids became extinct at or immediately after the Hangenberg Event, and the morphospace left behind by these Devonian groups was reoccupied only incompletely by the surviving prionoceratid ammonoids.

25. This investigation concentrated on the development of the whorl expansion rate (WER), a character very important for ammonoids since it indicates the body chamber length and hence the orientation in the water column as well as mobility.