Two specimens of Campylonotus arntzianus sp. nov. were caught in the Antarctic Scotia Sea off Saunders Island (57°40,31ŽS, 26°27,81ŽW) using an Agassiz trawl at one station (depth: 475 to 589 m). The new species here described is the fifth representative of the monogeneric family Campylonotidae and the first of the family south of the Antarctic Convergence. Campylonotus arntzianus sp. nov. is a shrimp of about 5 cm in total length. Due to similarities in adult morphology, C. arntzianus sp. nov. seems to be closely related to C. capensis, a deep-sea species from the Southern Atlantic Ocean. A simple key for the species identification of the Campylonotidae is provided.