Yochelcionella is an extinct
genus of basal
molluscs which lived during the
Tommotianepoch, the first epoch of the
Cambrian period. This genus is often reconstructed to resemble
snails.
This genus of molluscs possessed shells which were shaped like curved caps, with an
exhaust pipe shaped "
snorkel" emanating underneath where the apex (point of the shell) curves over. It is believed that the "snorkel" was used in breathing, allowing waste water to flow away from the
gills.
Taxonomy
When they were first discovered, they were originally thought to be
monoplacophorans. Their snorkel may represent a move towards a tubular shell, such as is seen in the modern
scaphopods.[3] It has also been interpreted as a precursor to the cephalopod funnel[4] or siphuncle.[5]
Yochelcionella cyrano Runnegar and Pojeta 1974
type species. Its type locality is ANU Collection 10352, 16 km northeast of Mootwingee Aboriginal Site, which is in a Solvan carbonate limestone in the Coonigan Formation of Australia..
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abVendrasco M. J., Porter S. M., Kouchinsky A., Li G. & Fernandez C. Z. (2010). "New data on molluscs and their shell microstructures from the Middle Cambrian Gowers Formation, Australia". Palaeontology53(1): 97-135.
doi:
10.1111/j.1475-4983.2009.00922.x.