Microanatomy of the Central Nervous System of Gammarus Setosus Dementieva (Amphipoda). The Supraoesophageal Ganglion (Brain)

Compared to other amphipods, the brain of Gammarus setosus resembles closely that of the freshwater Gammarus pulex. Major differences between these two gammarids are found in the location, number, and degree of differentiation of the neuropiles, with some modification in the extent and location of the cellular glomeruli overlying the surface of the brain. G. setosus has well developed sensory facilities manifested in the antennal I and II neuropiles, the presence of large, well differentiated olfactory and optic lobes, neuropiles, and tracts, as well as smaller but distinct paraolfactory and accessory lobes. Centers of nervous integration, such as the central body and medulla terminalis, are also prominent.