Commonly called kelp crabs, these crabs generally are found among algae.

Key to species of family Epialtidae

1. Five free abdominal segments in both sexes. Rostrum with shallow apical notch. Carapace nearly smooth, with broad hepatic, branchial lobes........................................................................ Epialtoides hiltoni

– Seven free abdominal segments in both sexes. Rostrum bifid. Carapace smooth or with tubercles, with or without lobes.... 2

2. Antennae not visible at sides of rostrum in dorsal view. Carapace broadly oval, smooth................. Taliepus nuttallii

– Antennae visible at sides of rostrum in dorsal view. Carapace varying in shape, smooth or with tubercles................ 3

3. Carapace with broad lateral expansions, leaf-like branchial expansion overlapping hepatic region dorsally.. Mimulus foliatus

– Carapace without broad lateral expansions, expansions inwardly separated........................................ 4

4. With smaller secondary spine between postorbital, hepatic spines at slightly lower level. South of Point Conception to northern Mexico............................................................................... Pugettia venetiae

– Without smaller secondary spine between postorbital, hepatic spines at slightly lower level. May range north of Point Conception................................................................................................ 5

5. Hepatic projection a transverse spine not joined with postorbital spine by lateral expansion of carapace. Postorbital projection consisting of ovate lobe directed forward........................................................ Pugettia dalli

– Hepatic projection a triangular tooth, joined completely or incompletely with postorbital spine by lateral expansion of carapace. No such ovate lobe................................................................................ 6

6. Carapace smooth, sides subparallel. No constriction between hepatic, branchial tooth................. Pugettia producta

– Carapace tuberculate, sides not subparallel. Constriction between hepatic, branchial tooth............................ 7

7. Tubercles of carapace uneven in size. Hepatic tooth broadly joined to postorbital, its outer margin trending toward longitudinal...................................................................................... Pugettia gracilis

– Tubercles of carapace even in size. Hepatic tooth deeply separated from postorbital, its outer margin trending toward transverse.................................................................................... Pugettia richii