Length: 5-12mm. Angular fore-head; pereonites 1-5 smooth; pereonites 5 - 7 with single pair dorsal projections. Antenna 1 as long as ½ body length; antenna 2 as long as antenna 1 peduncle articles 1 + 2. Propodus of gnathopod 1 with 2 grasping spines, grasping margin of dactylus and propodus serrate. Gnathopod 2 attached posterior to median of pereonite 2; basis curved at distal end and having two small antero-dorsal ridges; ischium with antero-lateral rounded projection; propodus with tufts of setae antero-dorsally and on sides of palmar projections, palm with proximo-medial projection with grasping spine and accessory spine, distal acute poison tooth and more distal triangular projection; dactylus somewhat scimitar-shaped with serrate grasping margin. Gills oval to oblong. Pereopods 5 - 7 propodus with three tufts of truncated spines on palm, convex outer surface with tufts of long setae.
Pacific coasts of Korea and China; Korean Straits; Japan; California
Probably named for short head spine
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.
45-182m. Hydroids, algae and abalone shell
National Museum of Natural History, Washington DC: (NMNH) 154967; Rock Slide Between Pelican + Prisoners; Santa Cruz Is; 1939 collected by Willis G Hewatt
