Better Than Crabs!


Domain: Eukarya

Kingdom: Animalia

Phylum: Arthropoda

Superclass: Crustacea

Class: Malacostraca

Order: Decapoda

Family: Nephropidae

Genus: Homarus

Species: H. americanus


    The American lobster is classified as a member of the Domain Eukarya because of

    the presence of a true nucleus as well as specialized, membrane-bound organelles.


    Members of the Kingdom Animalia are multicellular as well as heterotrophic (they

    rely on other organisms for direct supply of nutrition via ingestion).


    The Phylum Arthropoda is the

    most abundant and diverse

    eukaryotic phylum and includes

    organisms that are bilaterally

    symmetrical invertebrates that

    have complex jointed exoskeletons

    that allow for movement.  These

    organisms also have segmented

    bodies and their bodies are

    separated into distinct head and

    trunk regions (but the trunk can be

    separated further into a thorax

    and abdomen). Typically, these

    organisms develop eyes and molt

    often to allow for body size



    Crustaceans are organisms that live primarily in aquatic environments and are

    protected by the presence of a chitinous exoskeleton (which also gives support for

    the attachment of muscles). Their segmentation is even more distinct with

    cephalothroax and abdomen regions.  Additional characteristics include two pairs of

    antennae (which aid in sensory perception) and complex eyes on stalks.


    Members of the Class Malacostraca include

    the larger species of Crustaceans.  The

    segmentation of these organisms is as follows:

    the head consists of five segments, eight

    segments compose the thorax, and six or

    seven segments make up the abdomen. 

    However, not all species have a cephalothorax.

    Generalizations about this Class are difficult to

    maintain because the species are so varied.


    The Order Decapoda contains organisms with ten legs, which are the last five pairs

    of thoracic appendages, they’ve just been modified into legs used for locomotion;

    however, the front pair of walking legs may have enlarged pinchers, which are

    called chelipeds. The first three pairs, which function as mouth parts, are referred to

    as the maxillipeds.


    The Family Nephropidae is

    also referred to as the family

    of clawed lobsters, and these

    claws are usually highly

    specialized and unequal in

    size due to favoritism; the

    larger of the two claws

    becomes the crusher claw,

    while the smaller claw is the



    The members of the Genus Homarus include the American lobster (H. americanus)

    and the European lobster (H. gammarus), two of the most commercially popular

    lobster species.  These two species are extremely difficult to differentiate and can

    only be done so by examining habitat (western vs. eastern Atlantic) as well as the

    presence of teeth on the underside of the rostrum, which is an extension of the



    The Species H. americanus is found in the northwestern portion of the Atlantic

    Ocean. This organism not only provides meat from its tail, but also from it’s claws.

    So please continue this journey and learn more about this incredible creature!

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