A KEY TO ALL KNOWN SPECIES OF OEDICERINA: 1a. Rostrum strongly deflexed, the angle between the head dorsal margin and rostrum margin c. 90 ° (Fig. 1A) ........................................................................................................................................................................... 21b. Rostrum curved but not strongly deflexed, the angle between the head dorsal margin and rostrum margin distinctly larger than 90 ° (Fig. 1B) ................................................................................................................. 5 2a. Coxa 1 distinctly wider than deep (width length ratio 1:0.7), anterodistal corner narrowly rounded ........... ............................................................................................................................................................ O. henrici2b. Coxa 1 slightly wider than deep or as wide as long (width length ratio 1:0.8–1.0), anterodistal corner broad, bluntly rounded..................................................................................................................................................3 3a. Gnathopod 2 palm straight, maxilliped palp article 3 strongly produced along article 4 ..... O. megalopoda3b. Gnathopod 2 palm strongly convex, maxilliped palp article 3 slightly or not produced along article 4 ...... 4 4a. Coxae 1–3 setose (long curled setae), pereopod 7 posterior margin of basis with long plumose setae, posterodistal lobe absent ............................................................................................................ O. denticulata 4b. Coxa 1–3 sparsely setose (short setae), pereopod 7 posterior margin of basis naked, posterodistal lobe absent ................................................................................................................................................... O. vaderi 4c. Coxae 1–3 naked, pereopod 7 posterior margin of basis naked, posterodistal lobe present, nearly as long as ischium ................................................................................................................................................ O. claudei 5a. Pereonite 7 with posteriorly directed tooth, gnathopod 1 dactylus distinctly longer than palm ... O. teresae5b. All pereonites smooth posteriorly, gnathopod 1 dactylus as long as palm or only minutely longer than palm ........................................................................................................................................................................... 6 6a. Pleonite 3 smooth posteriorly, pereopod 7 posterodistal lobe present, almost as long as ischium. O. loerzae6b. Pleonite 3 with small upright tooth, pereopod 7 posterodistal lobe absent................................................... 7 7a. Coxa 4 anterior margin slightly expanding distally, coxa the widest almost at the anterodistal corner, maxilliped palp article 3 distinctly produced along article 4 ............................................................... O. lesci 7b. Coxa 4 anterior margin slightly expanding distally, coxa the widest at 2/3 of its length, maxilliped palp article 3 slightly produced along article 4 ......................................................................................... O. ingolfi