The Japanese skeleton shrimp Caprella mutica, originally from the north-west Pacific, artificially introduced to many parts of the world, is recorded in Sweden for the first time. The new record is from Eastern Skagerrak, slightly north of the border between the North Sea and the Baltic Sea. A detailed morphological description of the specimens from Swedish waters with notes on habitat is presented. In comparison with the specimens from the native range, the large males of C. mutica from Sweden, and material earlier reported from elsewhere in Europe, are characterized by rather long pereonites 1 and 2, which are longer than the combined length of pereonites 3 and 4; and long segments of antenna 1 peduncle; among them segment 3 is longer than flagellum.
