e/Torsion (gastropod)

Information
has gloss	eng: Torsion is an unusual anatomical event which takes place during the very early part of the life of snails and slugs of all kinds. In other words, torsion is a gastropod synapomorphy which occurs in all gastropods during larval development. Torsion is the rotation of the visceral mass, mantle and shell 180˚ with respect to the head and foot of the gastropod. This brings the mantle cavity and anus to an anterior position above the head.
lexicalization	eng: torsion
instance of	(noun) snails and slugs and their relatives class Gasteropoda, Gasteropoda, class Gastropoda, Gastropoda

Media
media:img	Haliotis asinina protoconch.jpg
media:img	Haliotis asinina trochophore protoconch.jpg