Catecholaminergic neurons in the brain of rotifers

In 10 rotifer species from the subclasses Archeorotatoria (order Bdelloidea ) and Eurotatoria (superorders Gnesiotrocha and Pseudotrocha) three pattern s of catecholaminergic neurons are detected, namely: x-shaped, arch-shaped and ring-shaped. These brain complexes are developed independently and in a parallel fashion in different rotifer groups. The number of the brain cate cholaminergic neurons varies from 6 to 11, constituting about 3-7% of the t otal number of the brain cells. The brain neuron pattern demonstrates a dis tinct bilateral symmetry.