crustacea: class of mandibulate arthropods including: lobsters; crabs; shrimps; woodlice; barnacles; decapods; water fleas
entity: that which is perceived or known or inferred to have its own distinct existence (living or nonliving)
calandrinia: large genus of low-growing herbs; widespread throughout tropical and warm temperate regions having usually basal leaves and panicles of purplish ephemeral flowers