Break it Down Now!
A Limulus polyphemus in
Young child examining an empty horseshoe
Photographer: Mary Hollinger, NODC
What Exactly Am I?
A horseshoe crab is apart of the eukarya
domain because it is a multicellular species
whose cells contain a true nucleus as well
as membrane bound organelles.
This organism is part of the animalia
kingdom because it is multicellular and has
to obtain food by eating and digesting other
organisms which means that they are
heterotrophic. Their cells have a cell
membrane but not a cell wall which is
another characteristic of the animalia
A horseshoe crab is part of the phylum arthropoda. It has five pairs of jointed-legs and is also a invertebrate, meaning an animal without a backbone. This organism has a chitinous exoskeleton and grows by molting. Want to learn more about some different arthropods? Click here to explore the world of the deer tick and here for the yetti crab!
Above: An overturned horseshoe
A horseshoe crab is part of the cheilcerata because it lacks jaws.
The horseshoe crab is a merostomata
because its legs surround the mouth.
The horseshoe crab has a sword tail which
the Xiphos- Greek prefix means sword. The –ura
suffix means tail therefore placing it in
the Xiphosura subclass.
Members of the limulidae family only
contain the four species of horseshoe crabs,
therefore, limulidae means horseshoe crab.
The horseshoe crab has compound
eyes that are sideways therefore is part of
genus. Limulus is a Latin term
meaning slanting, unusual, or crooked.
The horseshoe crab has simple eyes
located on the front of the shell
categorizing this organism as
polyphemus species. The Greek
term polyphemus signifies a one-eyed giant.
Limulus polyphemus -Limulus
is a Latin term which means slanting,
unusual, or crooked. -polyphemus is
a Greek term that signifies a one-eyed
This phylogenetic tree represents a broad morphological classification starting with eukarya and increase in complexity as it moves farther down the tree.
The closest relatives to the Limulus polyphemus are shown in this phylogenetic tree which is based on a morphological classification. All members in this tree are part of the family limulidae. Its closest relatives are the three other species of horseshoe crabs located in other areas in the world.
If you would like to learn about the habitat of the organism click here!
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