All Topics  
Hippoidea

 

 
   Email Print
   Bookmark   Link
 

 

Hippoidea
 
 
  Topics Hippoidea Topic Home

Hippoidea is a superfamily of decapod
Decapoda

The decapods or Decapoda are an order of crustaceans within the class Malacostraca, including many familiar groups, such as crayfish, crabs, lobsters, prawns and shrimp....
 crustacean
Crustacean

Crustaceans are a large group of arthropods, comprising almost 52,000 described species , and are usually treated as a subphylum . They include various familiar animals, such as crabs, lobsters, crayfish, shrimp, krill and barnacles....
s known as sand crabs or mole crabs .

oids are adapted
Adaptation

Adaptation is the process, which takes place under natural selection, whereby an organism becomes better suited to its habitat. Also, the term may refer to some characteristic which stands out as being especially significant in the organism's survival....
 to burrowing into sand
Sand

Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.As the term is used by geologists, sand particles range in diameter from 0.0625 to 2 millimeters....
y beach
Beach

File:MiamiSouthBeachPanoramaEdit.jpgA beach is a geology landform along the shoreline of a body of water. It usually consists of loose particles which are often composed of Rock , such as sand, gravel, shingle beach, pebbles, or cobble....
es, a habit they share with raninid
Raninidae

Raninidae is a family of unusual crabs named for their frog-like appearance, taken by most scientists to be quite primitive. These animals closely resemble the mole crabs, due to parallel evolution or convergent evolution....
 crabs, and the parallel evolution
Parallel evolution

Parallel evolution is the independent evolution of similar traits, starting from a similar ancestral condition due to similar environments or other evolutionary pressures....
 of the two groups is striking . The whole body is almost ovoid, the first pereiopods have no claw
Claw

A claw is a curved, pointed appendage, found at the end of a toe or finger in most mammals, birds, and some reptiles. Somewhat similar fine hooked structures are found in arthropods such as beetles and spiders, at the end of the leg or Arthropod leg for gripping a surface as the creature walks....
s, and the telson
Telson

The telson is the last division of the body of a crustacean. It is not considered a true segment because it does not arise in the embryo from teloblast areas as do real segments....
 is long, all of which characters are not seen in related groups .






Discussion
Ask a question about 'Hippoidea'
Start a new discussion about 'Hippoidea'
Answer questions from other users
Full Discussion Forum



Encyclopedia


Hippoidea is a superfamily of decapod
Decapoda

The decapods or Decapoda are an order of crustaceans within the class Malacostraca, including many familiar groups, such as crayfish, crabs, lobsters, prawns and shrimp....
 crustacean
Crustacean

Crustaceans are a large group of arthropods, comprising almost 52,000 described species , and are usually treated as a subphylum . They include various familiar animals, such as crabs, lobsters, crayfish, shrimp, krill and barnacles....
s known as sand crabs or mole crabs .

Ecology

Hippoids are adapted
Adaptation

Adaptation is the process, which takes place under natural selection, whereby an organism becomes better suited to its habitat. Also, the term may refer to some characteristic which stands out as being especially significant in the organism's survival....
 to burrowing into sand
Sand

Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.As the term is used by geologists, sand particles range in diameter from 0.0625 to 2 millimeters....
y beach
Beach

File:MiamiSouthBeachPanoramaEdit.jpgA beach is a geology landform along the shoreline of a body of water. It usually consists of loose particles which are often composed of Rock , such as sand, gravel, shingle beach, pebbles, or cobble....
es, a habit they share with raninid
Raninidae

Raninidae is a family of unusual crabs named for their frog-like appearance, taken by most scientists to be quite primitive. These animals closely resemble the mole crabs, due to parallel evolution or convergent evolution....
 crabs, and the parallel evolution
Parallel evolution

Parallel evolution is the independent evolution of similar traits, starting from a similar ancestral condition due to similar environments or other evolutionary pressures....
 of the two groups is striking . The whole body is almost ovoid, the first pereiopods have no claw
Claw

A claw is a curved, pointed appendage, found at the end of a toe or finger in most mammals, birds, and some reptiles. Somewhat similar fine hooked structures are found in arthropods such as beetles and spiders, at the end of the leg or Arthropod leg for gripping a surface as the creature walks....
s, and the telson
Telson

The telson is the last division of the body of a crustacean. It is not considered a true segment because it does not arise in the embryo from teloblast areas as do real segments....
 is long, all of which characters are not seen in related groups . Unlike most other decapods
Decapoda

The decapods or Decapoda are an order of crustaceans within the class Malacostraca, including many familiar groups, such as crayfish, crabs, lobsters, prawns and shrimp....
, sand crabs cannot walk
WALK

WALK may refer to:*WALK , a radio station licensed to East Patchogue, New York, United States*WALK-FM, a radio station licensed to Patchogue, New York, United States...
; instead they use their legs
Arthropod leg

The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments are of Latin origin, and may be confused with terms for bones: coxa , trochanter , femur, tibia, tarsus , ischium, metatarsus, carpus, dactylus , patella....
 to dig into the sand . Members of the family Hippidae beat their uropods to swim .

Apart from the polar region
Polar region

Earth polar regions are the areas of the globe surrounding the geographical pole also known as Geographical zone. The North Pole and South Pole being the centers, these regions are dominated by the polar ice caps, resting respectively on the Arctic Ocean and the continent of Antarctica....
s, hippoids can be found on beaches throughout the world. Larvae of one species have also been found in Antarctic waters
Southern Ocean

The Southern Ocean, also known as the Great Southern Ocean, the Antarctic Ocean and the South Polar Ocean, comprises the southernmost waters of the World Ocean south of 60th parallel south latitude....
, despite the lack of suitable sandy beaches in the Antarctic .

Classification

Alongside hermit crab
Hermit crab

Hermit crabs are Decapoda crustaceans of the superfamily Paguroidea . They are not closely related to true crabs. Hermit crabs are quite commonly seen in the intertidal zone, for example in tide pools....
s and allies (Paguroidea), squat lobster
Squat lobster

Squat lobsters are Decapoda crustaceans of the families Galatheidae and Chirostylidae, including the common genera Galathea and Munida....
s and allies (Galatheoidea) and the hairy stone crab
Hairy stone crab

The hairy stone crab, Lomis hirta, is a crab-like crustacean that lives in the littoral zone of southern Australia from Bunbury, Western Australia to the Bass Strait ....
 (Lomis hirta, Lomisoidea), Hippoidea is one of the four groups that make up the infraorder Anomura
Anomura

Anomura is a group of Decapoda crustaceans, including hermit crabs and others. Although the names of many anomurans includes the word crab, all true crabs are in the sister group to the Anomura, the Brachyura ....
 . Of the four, Hippoidea is thought to be the most basal
Basal (phylogenetics)

In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group form an outgroup to the rest of the clade, such as in the following example:...
, with the other three groups being more closely related to each other than to Hippoidea .

The fossil record of sand crabs is sparse , but extends back to the Cretaceous
Cretaceous

The Cretaceous , usually abbreviated K for its German translation Kreide, is a geologic period from circa to million years ago . In the geologic timescale, the Cretaceous follows on the Jurassic period and is followed by the Paleogene period....
 period .

Sand crabs are placed in three families († represents exclusively fossil taxa) : Albuneidae
  • Albunea
  • Austrolepidopa
  • Harryhausenia† 
  • Italialbunea†
  • Leucolepidopa
  • Lepidopa
  • Paraleucolepidopa
  • Paralbunea
  • Praealbunea† 
  • Squillalbunea
  • Stemonopa
  • Zygopa
Blepharipodidae
  • Blepharipoda
  • Lophomastix

Hippidae
  • Emerita
    Emerita (genus)

    Emerita is a genus of oval-shaped crustaceans found on the Atlantic Ocean and Pacific Ocean coasts of North America and South America. Emerita are popularly known as mole crabs, sand fleas, sand crabs, beach hoppers, or even more colloquially as lookie cookies....
  • Hippa
  • Mastigochirus
  • Mastigopus