Hierarchy of ranks:
– Order is one of the eight major hierarchical taxonomic ranks.
– It is classified between family and class.
– The order is a taxonomic rank used in the classification of organisms.
– Superorder is sometimes added directly above order, with suborder directly beneath order.
– An order can be defined as a group of related families.
Zoology:
– In zoology, additional classifications are sometimes used.
– Michael Novacek and Michael Benton suggested different positions for these classifications.
– The position adopted by Systema Naturae 2000 places them between superorder and magnorder.
– Some clades covered by the International Code of Zoological Nomenclature use these classifications.
– Not all additional classifications are officially recognized in zoology.
Botany:
– In botany, subclass and suborder are secondary ranks pre-defined above and below the rank of order.
– Further ranks can be used as long as they are clearly defined.
– The superorder rank is commonly used in botany.
– The ending “-anae” is used for superorders.
– Armen Takhtajan initiated the use of the superorder rank in botany.
History:
– The order as a distinct rank of biological classification was first introduced by Augustus Quirinus Rivinus.
– Carl Linnaeus applied the order consistently to the division of all three kingdoms of nature.
– Some plant families still retain the names of Linnaean natural orders.
– In zoology, Linnaean orders refer to natural groups.
– Some of Linnaeus’s ordinal names in zoology are still in use today.
Virology:
– The International Committee on Taxonomy of Viruses virus classification includes fifteen taxa.
– These taxa are applied for viruses, viroids, and satellite nucleic acids.
– There are currently fourteen viral orders, each ending in the suffix “-virales”.
– The viral classification includes orders, families, genera, and species.
– The classification system for viruses is extensive and detailed.
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Order (Latin: ordo) 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.
What does and does not belong to each order is determined by a taxonomist, as is whether a particular order should be recognized at all. Often there is no exact agreement, with different taxonomists each taking a different position. There are no hard rules that a taxonomist needs to follow in describing or recognizing an order. Some taxa are accepted almost universally, while others are recognized only rarely.
The name of an order is usually written with a capital letter. For some groups of organisms, their orders may follow consistent naming schemes. Orders of plants, fungi, and algae use the suffix -ales (e.g. Dictyotales). Orders of birds and fishes use the Latin suffix -iformes meaning 'having the form of' (e.g. Passeriformes), but orders of mammals and invertebrates are not so consistent (e.g. Artiodactyla, Actiniaria, Primates).