They are group of phospholipids found in platelets. their hydrolysis produces aldehydes which help in coagulation

Plasmalogens are found in numerous human tissues, with particular enrichment in the nervous, immune, and cardiovascular system.[1][2][3] In human heart tissue, nearly 30-40% of choline glycerophospholipids are plasmalogens. Even more striking is the fact that almost 30% of the glycerophospholipids in the adult human brain and up to 70% of myelin sheath ethanolamine glycerophospholipids are plasmalogens.[4]

Although the functions of plasmalogens have not yet been fully elucidated, it has been demonstrated that they can protect mammalian cells against the damaging effects of Reactive oxygen species.[1][2][3] In addition, they have been implicated as being signaling molecules and modulators of membrane dynamics.