Definition of Crustacea in US English:


plural noun

  • 1A large group of mainly aquatic arthropods that include crabs, lobsters, shrimps, wood lice, barnacles, and many minute forms. They are very diverse, but most have four or more pairs of limbs and several other appendages.

    Subphylum (or phylum) Crustacea

    • ‘They are, of course, a member of the Crustacea class, but where other crabs, lobsters and shrimps develop their own protection with a hard outer shell, the hermit crab appears to have managed to evolve only halfway through this process.’
    • ‘Hemocyanin is the only respiratory protein available to the Chelicerata and the Myriapoda, while in the Crustacea, either hemocyanin or hemoglobin occurs.’
    • ‘With around 35,000 known species the Crustacea are a diverse group.’
    • ‘While the fossil records of the Mysida and Lophopgastrida are among the best known of the malacostracan Crustacea, fossil representatives of these groups are still relatively rare.’
    • ‘Hemocyanins have been studied thoroughly only in the Chelicerata and the malacostracan Crustacea, but they have been identified in all arthropod subphyla, including the Myriapoda and Hexapoda.’
    • ‘Foote also suggested that using an extremely broad rank, such as class, would offer less information in this specific case, because the classes themselves, such as Crustacea, are notably disparate.’
    • ‘Generations of morphologists have been unable to determine the branching order of Chelicerata, Myriapoda, Crustacea and Insecta.’
    • ‘As this research continues, it is anticipated that studies of paleobiogeography and paleoecology will increasingly rely on data from the fossil record of the decapod Crustacea.’
    • ‘However, cladistic analysis indicates that the Cycloidea possibly belong within the Crustacea as a sister group of the Copepoda.’
    • ‘Pelagic species were from the Chaetognatha, Cnidaria, Crustacea, Ctenophora, and Mollusca, and benthic species were from the Chordata, Crustacea, Mollusca, and Echinodermata.’
    • ‘The Socorro isopod is a member of the order Isopoda, which is distinguished from other orders of the class Crustacea by its flattened body and seven pairs of legs.’
    • ‘Arthropods have traditionally been divided into four classes: Trilobita, Chelicerata, Crustacea, and Uniramia.’
    • ‘The complete sequence of the mitochondrial genome of the giant tiger prawn, Penaeus monodon (Arthropoda, Crustacea, Malacostraca), is presented.’
    • ‘The defense of mating sites is exhibited by several species of aquatic Crustacea.’
    • ‘The search for the rootstock of the decapod Crustacea has resulted in the discovery of numerous Paleozoic organisms that bear some similarity to Mesozoic and Cenozoic shrimp, lobsters, and crabs.’
    • ‘This exceptional situation, completely unexpected, seems to provide strong support for MF being a reproductive hormone in Crustacea.’
    • ‘The spectacular diversity of eye types of adult marine Crustacea does not appear in their larval eyes, all of which have a transparent apposition design.’
    • ‘The focus of this paper is on the Crustacea, the class of Arthropoda that expresses both hemoglobin and hemocyanin.’
    • ‘Now a team of paleontologists has found a fossilized arthropod they're betting is an early member of the subphylum Crustacea.’
    • ‘This would not be surprising if we consider extant marine arthropods such as Crustacea where it is usual that two or more planktonic larval stages occur prior to metamorphosis.’
    1. 1.1as plural noun crustacea Arthropods of the group Crustacea.
      • ‘Regarding flies, the sea trout you are hunting is a highly efficient ocean predator used to chasing sand eel, smaller fish fry and crustacea.’
      • ‘It is also a home for rare whales and weird fish, the breeding ground for two-and-a - half million seabirds and the silt in which dozens of previously unknown crustacea secrete themselves.’
      • ‘Sea lice are ectoparasitic marine crustacea which eat the membrane, skin and blood of their host.’
      • ‘Both adults and juveniles feed on benthic algae as well as on benthic and planktonic crustacea.’
      • ‘Allergic reactions to molluscs, and consequently mollusc allergens, have not been as well studied as those of fish or crustacea.’
      • ‘Darwin's barnacles, which showed just such specializations in adult life had not been recognized to be crustacea until their less modified and obviously crustacean larvae had been identified.’
      • ‘It was a beautiful wooden skiff, with a little outboard motor, perfect for his part-time second occupation of working a few pots to catch crustacea to sell to local pubs and restaurants.’
      • ‘The fish life was as varied as anywhere in the Caribbean, but especially notable were the grouper and huge crustacea.’
      • ‘They were out at the crab-huts, awaiting the moment the crustacea shed their shells, to pluck them from watery trays and packed off to dinner-tables in New York and London.’
      • ‘Add to that a lush mountainous island that grows plentiful herbs and vegetables, surrounded by a sea teeming with great fish and crustacea, and you're in for a gastronomic treat.’
      • ‘The diet of Nile perch consists of fishes, insects, crustacea and mollusks.’
      • ‘Fish eat snails in their shells and hard-shelled crustacea as well as invertebrates with exoskeletons.’
      • ‘And he is particularly informed and particularly informative about marine animals - fish, crustacea, cephalopods, testacea.’
      • ‘Such is the price of prime white fish and crustacea, most restaurants pad it out unless they can afford to charge exceptional sums.’
      • ‘Here in Scotland we are lucky to have many stocked fisheries set in more natural surroundings than their southern counterparts, where the trout soon become accustomed to a natural diet of insects and crustacea.’


Modern Latin (plural), from crusta (see crust).