Length: 19.8-34.4mm. Head and body without dorsal spines, but with many large and small tubercles, particularly on dorsal surface; lateral spines present over gnathopod 2 insertions, over gills and anteriorly on pereonite 3. Antenna 1 equal in length to cephalon plus pereonite 2; antenna 2 longer than peduncle of antenna 1, with strong swimming setae. Gnathopod 1 propodus triangular, with one pair of proximal grasping spines; grasping margin of propodus and dactylus finely denticulate. Gnathopod 2 basis short, with lateral and medial anterior spines; ischium with lateral and medial anterior spines; propodus with slight antero-distal projection, tuberculate anteriorly, palm laterally setose, bearing proximal projection with single grasping spine, and two triangular distal projections forming a u-shaped groove; dactylus strong, evenly tapered, denticulate along grasping margin. Gills elliptical. Pereopods 5 - 7 propodus with grasping spines. Female differs in having an accessory spine adjacent to the grasping spine.
Arctic ocean, Alaska; Coos Bay, OR; western Greenland
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.
Washed ashore on Sandy Beach in Oregon
National Museum of Natural History, Washington DC: (NMNH) 134426-7
