| Carinacea Temporal range: | |
|---|---|
 | |
| Paracentrotus lividus | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Echinodermata |
| Class: | Echinoidea |
| Subclass: | Euechinoidea |
| Infraclass: | Carinacea Kroh & Smith, 2010 |
| Superorders | |
The infraclassis Carinacea includes most living species of regular sea urchin, and fossil forms going back as far as the Triassic.
List of orders according to World Register of Marine Species:
 | This article about a sea urchin is a stub. You can help Wikipedia by expanding it. |
Order is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. An immediately higher rank, superorder, is sometimes added directly above order, with suborder directly beneath order. An order can also be defined as a group of related families.
Chilognatha is a subclass of the class Diplopoda, which includes the vast majority of extant millipedes, about 12,000 species.
Subclass Coleoidea, or Dibranchiata, is the grouping of cephalopods containing all the various taxa popularly thought of as "soft-bodied" or "shell-less". Unlike its extant sister group, Nautiloidea, whose members have a rigid outer shell for protection, the coleoids have at most an internal cuttlebone, gladius, or shell that is used for buoyancy or support. Some species have lost their cuttlebone altogether, while in some it has been replaced by a chitinous support structure. A unique trait of the group is the ability to edit their own RNA.
Australidelphia is the superorder that contains roughly three-quarters of all marsupials, including all those native to Australasia and a single species — the monito del monte — from South America. All other American marsupials are members of the Ameridelphia. Analysis of retrotransposon insertion sites in the nuclear DNA of a variety of marsupials has shown that the South American monito del monte's lineage is the most basal of the superorder.
The subclass Euechinoidea includes almost all living species of sea urchin, and fossil forms going back as far as the Triassic.
Monadofilosa is a grouping of Cercozoa. These organisms are single-celled amoeboid protists.
Anomalodesmata is an superorder of saltwater clams, marine bivalve molluscs. This grouping was formerly recognised as a taxonomic subclass. It is called a superorder in the current World Register of Marine Species, despite having no orders, to parallel it with sister taxon Imparidentia, which does have orders.
The Diplostraca or Cladocera, commonly known as water fleas, are a superorder of small crustaceans that feed on microscopic chunks of organic matter.
Neocoleoidea is a large group of marine cephalopods. This cohort contains two extant groups: Decapodiformes and Octopodiformes. Species within this group exist in all major habitats in the ocean, in both the southern and northern polar regions, and from intertidal zones to great depths. Whilst conventionally held to be monophyletic, the only morphological character for the group is the presence of suckers: although the presence of these features in the belemnites suggests that they do not support the Neocoleoidea, and hence that the group may be paraphyletic.
Temnopleuridea is an infraorder of sea urchins in the order Camarodonta. They are distinguished from other sea urchins by the presence of large fused plates on top of the feeding lantern. The test is usually sculpted to some degree, and has perforated tubercles.
The Salenioida are an order of sea urchins.
The Echinacea are a superorder of sea urchins. They are distinguished by the presence of a rigid test, with ten buccal plates around the mouth, and solid spines. Unlike some other sea urchins, they also possess gills. The group is a large one, with species found worldwide.
The Echinothurioida are an order of sea urchins in the class Echinoidea. Echinothurioids are distinguished from other sea urchins by the combination of a flexible test and hollow spines. The membrane around the mouth contains only simple plates, in contrast to the more complex mouth parts of their close relatives, the Diadematoida. They are nearly all deepsea dwellers.
The Camarodonta are an order of globular sea urchins in the class Echinoidea. The fossil record shows that camarodonts have been in existence since the Lower Cretaceous.
Holasteroida is an order of irregular sea urchins.
The Neognathostomata are a superorder of sea urchins.
The Echinothuriidae are a family of sea urchins in the order Echinothurioida. Due to their soft skeletons, most are called "leather urchins", but species in the genus Asthenosoma are also known as "fire urchins" due to their bright colors and painful, venomous sting.
The clade Multicrustacea constitutes the largest superclass of crustaceans, containing approximately four-fifths of all described crustacean species, including crabs, lobsters, crayfish, shrimp, krill, prawns, woodlice, barnacles, copepods, amphipods, mantis shrimp and others. The largest branch of multicrustacea is the class Malacostraca.
Saleniidae is a family of echinoderms belonging to the order Salenioida.
Ventrifilosa is a highly diverse group of phagotrophic protists that glide through their flagella and emit filose pseudopods from their ventral side for feeding. Because of their mixture of amoeba and flagellate characteristics, they are amoeboflagellates. Members of this group are the Imbricatea, Sarcomonadea and Thecofilosea.