Retrocerebral organ Despite over 100 years of research, rotifer anatomy still has many poorly understood components. One of the more mysterious organs in rotifers is the "retrocerebral organ" (RCO), which still remains very enigmatic in its morphology, function, development, and evolution. Lying close to the brain, this organ usually consists of one or more glands and a sac or reservoir. The sac drains into a duct before opening through pores on the uppermost part of the head. Current data shows a wide diversity in structure and potential function. Fontaneto, D., & De Smet, W. H. (2015). Rotifera, chapter 4 Handbook of Zoology, Gastrotricha, Cycloneuralia and Gnathifera, Volume 3, Gastrotricha and Gnathifera Schmidt-Rhaesa, Andreas. In some species it is reduced or may even be absent completely. Benthic species have larger RCO's than planktonic species. Despite this diversity, positional correspondence of RCOs strongly suggests homology.Robert Lee Wallace. "Rotifers: Exquisite Metazoans". 2002.
Retrocerebral organ Despite over 100 years of research rotifer anatomy still has many poorly understood components One of the more mysterious organs in rotifers is the "retrocerebral organ" (RCO) which still remains very enigmatic in its morphology function development and evolution Lying close to the brain this organ usually consists of one or more glands and a sac or reservoir The sac drains into a duct before opening through pores on the uppermost part of the head Current data shows a wide diversity in structure and potential function Fontaneto D & De Smet W H (2015) Rotifera chapter 4 Handbook of Zoology Gastrotricha Cycloneuralia and Gnathifera Volume 3 Gastrotricha and Gnathifera Schmidt-Rhaesa Andreas In some species it is reduced or may even be absent completely Benthic species have larger RCO's than planktonic species Despite this diversity positional correspondence of RCOs strongly suggests homologyRobert Lee Wallace "Rotifers Exquisite Metazoans" 2002