Length: 3.2-13mm. Body long and slender, head with gentle rise in middle dorsal surface; pereonite 2 with 3 pairs of dorsal spines and one or two lateral spines near gnathopods. Antenna 1 1/3 of body length; antenna 2 longer than peduncle of antenna 1, slender and finely setose, with two-segmented flagellum. Gnathopod 2 attached near middle part of pereonite 2; propodus palm with plumose setae and distal projection, forming a cleft. Pereopods 3 + 4 degenerated to 1-jointed lobe only, with several distal setae; pereopods 5-6 slender, six-segmented, pereopods 6 + 7 with palmar spines. Gills oval-shaped.
Tateyama Bay, Japan
Caprellid, "Ghost" or "Skeleton" shrimps, so called for their skeletal appearance. Amphipod crustaceans, easily distinguished by the elongate stick-like body form and reduction of the abdominal appendages. Head is generally fused with pereonite 1. Pereopods on first 2 segments (pereonites) are most flexible and called gnathopods; gnathopods 2 being the largest, used in defense, feeding and substrate attachment. In many species pereopods 3 and 4 may also be reduced or absent. Gills on pereonites 3 + 4, rarely on pereonite 2. Pereopods 5 - 7 much smaller than 1 + 2, used for clinging to the substratum. In females, brood plates (öostegites) develop on pereonites 3 + 4. Much remains to be learnt about their biology, ecology and in many cases changing distributions.
