Dikwa andresi, a new amphipod crustacean (Dikwidae) from the Scotia Arc

The new amphipod crustacean species Dikwa andresi from the Scotia Arc is described in detail. This is the first record of the family Dikwidae in the Southern Ocean. The white species was caught in water depth of 270–290 metres during the Antarctic autumn, living on the red hydrocoral (Hydrozoa) Errinopsis reticulum. It has a carinate pereon and pleon, no eyes and the head is telescoped into the first pereon segment. The first gnathopod is propodochelate, the second gnathopod is simple. The only known species of the family is Dikwa acrania from southern Africa. The new species mainly differs from D. acrania in having dorsal processes on all pereonites and the first coxa being twice as long as the second. An intraspecific variation of the shape of the telson was observed.