Search results
Results from the WOW.Com Content Network
They may have avoided predation by squirting ink, much like modern cephalopods; ink is occasionally preserved in fossil specimens. [34] Many ammonite shells have been found with round holes once interpreted as a result of limpets attaching themselves to the shells.
The anatomy of a common air-breathing land snail: much of this anatomy does not apply to gastropods in other clades or groups. Snails are distinguished by an anatomical process known as torsion, where the visceral mass of the animal rotates 180° to one side during development, such that the anus is situated more or less above the head. This ...
This list of marine gastropod genera in the fossil record is an attempt to list all the genera of sea snails or marine gastropod mollusks which have been found in the fossil record. Nearly all of these are genera of shelled forms, since it is relatively rare for gastropods without a shell ( sea slugs ) to leave any recognizable traces.
This genus is known in the fossil records from the Cretaceous to the Quaternary (age range: from 125.45 to 0.0 million years ago). Fossils of species within this genus have been found all over the world. There are about 25 known extinct species. [4] Murex altispira Fossil shell of Murex spinicosta from Pliocene of Italy
Fossil shells of E. tenera are hosted in chalcedony-rich sedimentary rock.This rock was originally incorrectly called Turritella agate. [7] It was named after the sea snail genus Turritella because of the resemblance of the freshwater snail shells to the Turritella fossils that are found in agate in Texas and California.
†Nerinea is an extinct genus of fossil sea snails, marine gastropod molluscs in the clade Heterobranchia. ... Fossils are known from various localities of Europe ...
Pikaia gracilens is an extinct, primitive chordate marine animal known from the Middle Cambrian Burgess Shale of British Columbia.Described in 1911 by Charles Doolittle Walcott as an annelid, and in 1979 by Harry B. Whittington and Simon Conway Morris as a chordate, it became "the most famous early chordate fossil", [1] or "famously known as the earliest described Cambrian chordate". [2]
The Vermetidae, the worm snails or worm shells, are a taxonomic family of small to medium-sized sea snails, marine gastropod molluscs in the clade Littorinimorpha. [1] The shells of species in the family Vermetidae are extremely irregular, and do not resemble the average snail shell, hence the common name "worm shells" or "worm snails".