Toxopneustidae is a family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 of globular sea urchin

Sea urchin

Sea urchins or urchins are small, spiny, globular animals which, with their close kin, such as sand dollars, constitute the class Echinoidea of the echinoderm phylum. They inhabit all oceans. Their shell, or "test", is round and spiny, typically from across. Common colors include black and dull...

s in the class

Class (biology)

In biological classification, class is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, order, family, genus, and species, with class fitting between phylum and order...

 Echinoidea.

Characteristics

All Camarodonts have imperforate tubercle

Tubercle

A tubercle is generally a wart-like projection, but it has slightly different meaning depending on which family of plants or animals it is used to refer to....

s and compound ambulacral plates. In addition, the Toxopneustids are characterised by the peristome

Peristome

The word peristome is derived from the Greek peri, meaning 'around' or 'about', and stoma, 'mouth'. It is a term used to describe various anatomical features that surround an opening to an organ or structure. The term is used in plants and invertebrate animals, such as in describing the shells of...

, or opening through the test, having a sharp margin with the buccal notches being prominent. The tubercles lack the crenulations or ring of cog-like structures that articulate with the spines in certain other families. The Aristotle

Aristotle

Aristotle was a Greek philosopher and polymath, a student of Plato and teacher of Alexander the Great. His writings cover many subjects, including physics, metaphysics, poetry, theater, music, logic, rhetoric, linguistics, politics, government, ethics, biology, and zoology...

's lantern, or jaw apparatus, has the keeled teeth and the epiphyses united above the foramen magnum, the V-shaped gap between the hemipyramids that support the lantern's tooth.

Genera

• Goniopneustes Duncan, 1889
• Gymnechinus Mortensen, 1903b
• Lytechinus A. Agassiz, 1863
• Nudechinus H.L. Clark, 1912
• Oligophyma Pomel, 1869
• Pseudoboletia Troschel, 1869
• Schizechinus Pomel, 1869
• Scoliechinus Arnold & H.L. Clark, 1927
• Sphaerechinus Desor, 1856
• Toxopneustes L. Agassiz, 1841b
• Tripneustes L. Agassiz, 1841b

See also

• Lytechinus variegatus
  Lytechinus variegatus
  Lytechinus variegatus, Lamarck, 1816 is a species of sea urchin that can be found in the warm waters of the western Atlantic Ocean. It has short spines and can reach a diameter of around 11 cm.-External links:* *...
  
  
• Toxopneustes pileolus
  Flower urchin
  The flower urchin is a species of sea urchin. It can inflict severe stings....
  
  
• Tripneustes gratilla
  Collector urchin
  The collector urchin is a species of sea urchin. Collector urchins are found at depths of in the waters of the Indo-Pacific, Hawaii, and the Red Sea. They can reach in size.-Description:...
  
  
• Tripneustes ventricosus
  Tripneustes ventricosus
  Tripneustes ventricosus, commonly called the West Indian Sea Egg, is a species of sea urchin. They are common in the Caribbean, Bahamas, and Florida, and may be found at depths of .-Description:...