Taken primarily from Kozloff, 1987, 1996 p.404 (Copyright 1987, 1996, University of Washington Press. Used in this web page by permission of University of Washington Press)
An excellent alternate key can be found in Wicksten,
2009 on page 194.
|Lower taxonomic level||Main Page||Alphabetic Index||Systematic Index||Glossary|
|1a||Rostrum bluntly rounded (photo) chela of larger cheliped, when closed, with a conspicuous gap between the dactyl and the clawlike process of the propodus (photo); carpus of smaller cheliped decidedly wider than the merus (photo); common intertidally in muddy sand||Neotrypaea californiensis|
|1b||Rostrum sharp; chela of larger cheliped, when closed, without a conspicuous gap between the dactyl and the clawlike process of the propodus; carpus of smaller cheliped not much wider than the merus; locally common intertidally and subtidally (to about 50 m) in muddy sand||Neotrypaea gigas|