Definition
Aplococeratidae is an extinct family of ammonoid cephalopods belonging to the subclass Ammonoidea. Members of this family are known from fossil records and are characterized by their coiled shells with complex suture patterns.
Overview
The Aplococeratidae family comprises several genera of marine mollusks that lived during the Late Paleozoic to Early Mesozoic eras. Their fossils have been recovered from sedimentary deposits in Europe, Asia, and North America, suggesting a relatively wide geographic distribution in ancient seas. The family is typically placed within the order Ceratitida, although some classifications have alternatively assigned it to the order Goniatitida.
Etymology / Origin
The name Aplococeratidae is derived from the type genus Aplococeras. The prefix “aplo‑” originates from the Greek ἀπλόος (aplóos), meaning “simple” or “unfolded,” while “‑ceras” comes from the Greek κέρας (kéras), meaning “horn,” a common element in the nomenclature of ammonoid taxa. The suffix “‑idae” denotes a taxonomic family.
Characteristics
- Shell morphology: Typically involute to moderately evolute shells with a rounded to compressed whorl section.
- Suture pattern: Complex sutures with lobes and saddles that are more intricately frilled than those of earlier goniatitid ammonoids, reflecting their placement within Ceratitida.
- Size: Shell diameters range from a few centimeters to over 20 cm, depending on the genus and species.
- Ecology: As nektonic predators, members of Aplococeratidae likely inhabited open marine environments, feeding on smaller marine organisms.
Related Topics
- Ammonoidea – the larger subclass encompassing all ammonoid cephalopods.
- Ceratitida – the order to which Aplococeratidae is most commonly assigned.
- Paleozoic and Mesozoic marine fauna – broader context of marine life during the time intervals when Aplococeratidae existed.
- Suture patterns in ammonoids – a key diagnostic feature used in ammonoid taxonomy.
Note: While the general characteristics and taxonomic placement presented above align with prevailing scientific literature, precise details regarding the temporal range and phylogenetic relationships of Aplococeratidae may vary among sources. Accurate information is not confirmed for all specific aspects of this family.