the horsetail crab is a detachment of aquatic helicera from the merostomy class. the name is given by the long xiphoid

animal aquarium arachnid arthropod arthropoda atlantic background beach biology cape casing closeup coast conceptual crab creative details domed environment florida fossil georgia gills horseshoe invertebrate large life limulus marine merostomata nature ocean outdoors polyphemus sand sandy sea seashore shell shore spikelike tail tropical unique unusual usa water wildlife xiphosurida