Actaecia euchroa Dana, 1853
Described from the Bay of Islands, common around North Island. Some records from the South Island (Westport) (Schmidt, 2002).
Found in the littoral zone on sandy beaches, on the surface or burying in the sand around high-water mark (Chilton, 1901).
Eyes seleniform (crescent-shaped). Animal is able to roll into a ball.
Can be confused with Scyphax ornatus - both species occur on sandy beaches (and frequently co-occur), both have seleniform eyes, and can have similar coloration. Live A. euchroa can be distinguished by the slow movement (S. ornatus runs very fast) and the ability to roll into a ball (S. ornatus does not roll). Both live and preserved A. euchroa can be distinguished by the shape of the uropods which are short and flattened, and do not extend far beyond the outline of the body (in S. ornatus the rami of uropods are spear-shaped and extend far beyond the outline of the body).