Image of grooved mussel crab

Description:

The dactyls are strongly curved. Setae on legs 3 and 4, especially on the dorsal edge of the merus, are long and featherlike. According to Hart (1982), the legs of gravid females have few setae while males and non-gravid females have many more setae (which may be used for swimming), plus hard carapaces. Hard individuals (mature males and non-gravid females) have more opaque carapaces, flatter legs, more long setae on the legs, and red articulations on the carapace. This individual seems intermediate between these conditions. This closeup dorsal view of the carapace shows the egg clusters in the gill chamber. The dorsal longitudinal grooves extending back from the orbits as well as the transverse groove can also be seen.