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Aspidorhynchid
Aspidorhynchidae (from Neo-Latin "shield-snouts") is an extinct Family (biology), family of Actinopterygii, ray-finned fish from the Mesozoic, Mesozoic Era. It is the only member of the Monotypic taxon, monotypic Order (biology), order Aspidorhynchiformes. Members of the group are noted for their elongated, conical Rostrum (anatomy), rostrums, of varying length, formed from fused premaxillae. The range of the group extends from the Middle Jurassic to the end of the Maastrichtian, with a potential record from the Thanetian, Late Paleocene. The family and order were described by Pieter Bleeker in 1859. Taxonomy Aspidorhynchiformes have generally been recovered as basal members of Neopterygii, Teleosteomorpha, more closely related to teleosts than to Holostei. They have often considered to have a sister group relationship with Pachycormiformes, another group of basal teleosteomorphs. However, other studies instead suggest that they successively diverged after one another, with the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richmondichthys
''Richmondichthys'' is an extinct genus of large prehistoric marine Actinopterygii, ray-finned fish known from the Early Cretaceous. It contains a single species, ''R. sweeti'' from the late Albian-aged Allaru Formation, Allaru and Toolebuc Formation, Toolebuc Formations of Queensland, Australia. At over in length, it is the largest known member of the Aspidorhynchiformes, Aspidorhynchidae, a group of primarily marine ray-finned fishes that were dominant throughout the latter half of the Mesozoic. It was initially described as a member of the aspidorhynchid genus ''Belonostomus'', with other fossil material being variously referred to ''Aspidorhynchus'' and ''Vinctifer'', until it was described in its own genus in 2004, being named after the town of Richmond, Queensland, Richmond. ''Richmondichthys'' differs from other aspidorhynchid genera both in its immense size, lack of a prominent Rostrum (anatomy), rostrum, and the lack of teeth while having hinged cheek bones. The latter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
