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Brancoceratidae
Brancoceratidae is a family of Acanthoceratoidea, acanthoceratoid Ammonitina, ammonites from the middle of the Cretaceous, recognized by their commonly evolute shells with round, oval, or quadrate whorls, strong ribs, usual ventral keels, and at least, umblical tubercles. The family is thought to be derived from the Desmoceratidae (Desmoceratoidea), perhaps from ''Silesitoides'' or some allied genus. Subfamilies The Brancoceratidae are divided into three subfamilies, described as follows. Brancoceratinae Spath, 1933: Generally small, evolute with round, oval, square or rectangular whorl sections. The venter may be sharp on the inner whorls, a feature which disappears on the later. Ribs are strong and rounded, and commonly cross over the venter. Sutures are simple, pseudoceratitc in some. The subfamily lived from during the Albian. Mojsisovicziinae Hatt, 1903: derived from the Broncoceratinae, beginning with ''Mojsisoviczia'', in which the keel has become a stable character, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acanthoceratoidea
Acanthoceratoidea, formerly Acanthocerataceae, is a superfamily of Upper Cretaceous ammonoid cephalopods belonging to the order Ammonitida, and comprising some 10 or so families.W.J Arkell ''et al''., Mesozoic Ammonoidea; Treatise on Invertebrate Paleontology, Part L, Ammonoidea. 1957 Diagnosis Members of the Acanthoceratoidea are typically strongly ribbed and have a tendency to develop prominent tubercles, although other types including those with oxyconic shells are included. Taxonomy Families included in the Acanthoceratoidea are: * Acanthoceratidae * Brancoceratidae * Coilopoceratidae * Collignoniceratidae * Flickiidae * Lyelliceratidae * Sphenodiscidae * Tissotiidae * Vascoceratidae Discussion According to Wright Calloman and Howarth, 1996 in the revised version of Part L of the Treatise, the Binneyitidae is replaced by the Forbesiceratidae with the Binneyitidae now in the Hoplitaceae and the Forbesiceratidae included in the Acanthoceratoidea. The Leymeriellidae Leyme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |