Ermoceras
Ermoceras Temporal range: Bajocian[1] | |
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Scientific classification | |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Subclass: | Ammonoidea |
Order: | Ammonitida |
Suborder: | Ammonitina |
Superfamily: | Stephanocerataceae |
Family: | Thomboceratidae |
Genus: | Ermoceras |
Ermoceras is a thomboceratid ammonite from the Middle Jurassic ( u Baj) of central Arabia, Sinai, and Algeria with strong primary and secondary ribs and a single row of lateral tubercles; described as having a deep ventral groove [2]
Telermoceras, with low, depressed whorls, and Kosmermoceras with high,compressed whorls are considered subgenera of Ermoceras [2] Both are from the same time and region. Telermoceras has coarse secondary ribs and a deep umbilicus surrounded by large tubercles or spines. Kosmermocerashas fine sharp to coarse ribbing and a flattish venter
Ermoceras s.l. is derived from Arkelloceras. Westermann (1965)[3] tentatively placed Ermoceras in the Thamboceratidae, based on sutural morphology, removing it from the Stephanoceratidae where it was previously included.
References
- ↑ Sepkoski, Jack (2002). "Sepkoski's Online Genus Database". Retrieved 2014-05-28.
- 1 2 Arkell et al 1957, Mesozoic Ammonoidea, Treatise on Invertebrate Paleontology, Part L, Ammonoidea
- ↑ Westernamm,G. E. G. 1965.Septal and Sutural Patterns in Evolution and Taxonomy of Thamboceratidae and Clydoniceratidae (M Jurassic Ammonitina).Jour of Paleontology 39(5)864-874, Sept