We also mapped the OA/TAMac receptor distribution by in-situ hybridization to the receptor's mRNA, and by immunohistochemistry to its protein. We observed stained cell bodies for the receptor's mRNA, mainly in the midline region of the thoracic and in the abdominal ganglia, as well as diffuse staining in the brain ganglia. For the receptor's protein, we observed extensive punctate staining within the neuropil and on the membrane of specific groups of neurons in all ganglia throughout the CNS, including the brain, the midline region and neuropiles of the thoracic ganglia, and ventral part and neuropiles of the abdominal ganglia. The same pattern of stained cells was observed on the thoracic and abdominal ganglia in both in-situ hybridization and immunohistochemistry experiments. Diffuse staining observed with in-situ hybridization also coincides with punctate staining observed in brain, SEG, thoracic, and abdominal ganglia in immunohistochemical preparations. This work provides the first step towards characterizing the neural networks that mediate octopaminergic signaling in prawn.