Taken primarily from Kozloff, 1987, 1996 p. 400 (Copyright 1987, 1996, University of Washington Press. Used in this web page by permission of University of Washington Press)
An excellent alternate, up to date key can be found in Wicksten, 2009 page 147
Here is a crangonid species captured from the Sea of Okhotsk off Kamchatka,
NW Pacific (not in key):
Argis
ochotensis
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| Lower taxonomic level | Main Page | Alphabetic Index | Systematic Index | Glossary |
| 1a | Rostrum more than half as long as the rest of the carapace; with only 4 pairs of legs | Paracrangon echinata |
| 1b | Rostrum, if present, less than half as long as the rest of the carapace (photo); with 5 pairs of legs | 2 |
| 2a | Dactyl of leg 5 broad and flattened; eyestalks parallel and shielded by a hood that consists of the antennal spines, postorbital spines, and rostrum | 3 |
| 2b | Dactyl of leg 5 not broad and flattened (photo); eyestalks not parallel and not shielded by a hood consisting of spines | 7 |
| 3a | Carapace with 2 median spines in addition to the spine that forms the rostrum | 4 |
| 3b | Carapace with 3 or 4 median spines in addition to the spine that forms the rostrum | 5 |
| 4a | Longitudinal dorsal ridges (carinae) on abdominal segment 6 extended beyond the posterior edge of the segment as spines | Argis dentata |
| 4b | Longitudinal dorsal ridges on abdominal segment 6 not extended beyond the posterior edge of the segment as spines | Argis lar |
| 5a | Longitudinal dorsal ridges (carinae) on abdominal segment 6 extended beyond the posterior edge of the segment as spines | Argis alaskensis |
| 5b | Longitudinal dorsal ridges on abdominal segment 6 not extended beyond the posterior edge of the segment as spines | 6 |
| 6a | Abdominal segments 1-4 with a longitudinal dorsal ridge; pleuron of abdominal segment 4 with a small posteroventral spine | Argis crassa |
| 6b | Abdominal segments 1-4 without a longitudinal dorsal ridge; pleuron of abdominal segment 4 without a posteroventral spine | Argis levior |
| 7a | Carapace with a median dorsal spine or spines (photo) | 8 |
| 7b | Carapace without median spines | Lissocrangon stylirostris |
| 8a | Submedian spines present on carapace | 9 |
| 8b | Submedian spines absent on carapace | 13 |
| 9a | Carapace with 2 submedian spines on both sides | Mesocrangon munitella |
| 9b | Carapace with 1 submedian spine on both sides (photo) | 10 |
| 10a | Pleura of abdominal segments 1-3 with ventrally directed spines | Metacrangon spinosissima |
| 10b | Pleura of abdominal segments 1-3 without ventrally directed spines | 11 |
| 11a | Anterior median carapace spine extending beyond the bases of the orbits of the eyes, and larger than the posterior median carapace spine | Metacrangon acclivis |
| 11b | Anterior median carapace spine not extending beyond the bases of the orbits of the eyes, and not larger than the posterior median carapace spine (photo) | 12 |
| 12a | Abdominal segments 3-5 with a prominent longitudinal dorsal ridge (carina); spine of scale of antenna 2 reaching to or beyond the tip of the lamella | Metacrangon variabilis |
| 12b | Abdominal segments 3-5 without a prominent longitudinal dorsal ridge; tip of the lamella of the scale of antenna 2 reaching beyond the spine (photo) | Metacrangon munita |
| 13a | Carapace obviously sculptured | 14 |
| 13b | Carapace smooth | 15 |
| 14a | Carapace with 1 or 2 median spines; outer margin of scale of antenna 2 (antennal scale) concave | Rhynocrangon alata |
| 14b | Carapace with 3 or 4 median spines; outer margin of scale of antenna 2 (antennal scale) convex | Sclerocrangon boreas |
| 15a | Carapace with 2 median spines | 16 |
| 15b | Carapace with 1 median spine (photo) | 18 |
| 16a | Rostrum ascending at an angle of about 45 degrees and extending beyond the eyes; rostrum, in adult, with a large ventral expansion | Neocrangon resima |
| 16b | Rostrum ascending at an angle of 30 degrees or less and not extending beyond the eyes; rostrum without a ventral expansion | 17 |
| 17a | Tip of rostrum rounded; eyes not contiguous | Neocrangon communis |
| 17b | Tip of rostrum acute; eyes large and contiguous | Neocrangon abyssorum |
| 18a | Dorsal surface of abdominal segment 6 with 2 prominent lateral ridges (carinae) | Crangon dalli |
| 18b | Dorsal surface of abdominal segment 6 without londitudinal ridges (photo) | 19 |
| 19a | Abdominal segment 5 with a spine on the upper posterolateral margin of both sides | 20 |
| 19b | Abdominal segment 5 without spines on the upper posterolateral margins (photo) | 21 |
| 20a | Dactyl of leg 1 reaching the base of the fixed finger when the chela is closed; propodus of leg 1 of male 4.5 times as long as wide | Crangon franciscorum
subspecies franciscorum |
| 20b | Dactyl of leg 1 crossing the base of the fixed finger when the chela is closed; propodus of leg 1 of male 5.5 times as long as wide | Crangon franciscorum
subspecies angustimana |
| 21a | Ventral surface of abdominal segment 6 with a median groove (sulcus) (photo) | 22 |
| 21b | Ventral surface of abdominal segment 6 without a median groove | Crangon alba |
| 22a | Flagella of antenna 1 equal in length; scale of antenna 2 (antennal scale) not more than twice as long as wide (not known to occur north of California) | Crangon handi |
| 22b | Inner flagellum of antenna 1 longer than the outer flagellum; scale of antenna 2 more than twice as long as wide (photo) | 23 |
| 23a | Spine of scale of antenna 2 (antennal scale) extending beyond the tip of the lamella, which is narrow (photo); scale of antenna 2 as long as, or longer than, the telson | Crangon alaskensis |
| 23b | Spine of scale of antenna 2 reached or exceeded by the tip of the lamella, which is a rounded lobe; scale of antenna 2 shorter than the telson | Crangon nigricauda |