Nervous system

Shrimps do not have any brain in the actual sense. It is a so called complex brain and lies in a nerve rope which runs along the body underside from the head down to the abdomen. The brain (Cerebral ganglion) lies directly above the gullet and consists of three ganglions (nerve knot), the procerebrum, the Deut cerebrum and the tricerebrum. These form affiliated together the largest ganglion, the so called Cerebral- or upper threat ganglion.

by Hans Gonella

Together with the lower throat ganglion that exists also of three parts, the single ganglion pairs and the nerve ropes the upper throat ganglions form the entire nervous system of shrimps.

In the further course these nerve ropes that are referred also as stomach marks are beside further segmental ganglion pairs that usually pull through all three body sections of the shrimp for which we also speak of a rope ladder nervous system.

The stomach mark consists of the lower throat ganglion (in the head), the three horakalganglions (in the breast section) and the abdominal ganglions (in the abdomen).

The lower throat ganglion which lies in the head area in the near of the mouth tools serves in the first line for the coordination of the mouth tools and in this way for the absorption of nutrients.

Three ganglion pairs the so called thoraxalganglions lie in the thorax (breast section). They form the peripheral nervous system and are used basically for the coordination of the movement of the muscles, striding legs and so they help the shrimp to move with that.

Also near the abdomen we can find the so called abdominal ganglions which form the vegetative nervous system. These coordinate the activity of the internal organs, in particular the sex organs. According to the situation whether upper- or below the throat (throat, neck) they are designated as an upper and lower throat ganglion.