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.
22-608: Stylonurina is one of two suborders of eurypterids , a group of extinct arthropods commonly known as "sea scorpions". Members of the suborder are collectively and informally known as "stylonurine eurypterids" or "stylonurines". They are known from deposits primarily in Europe and North America , but also in Siberia . Compared to the other suborder, Eurypterina , the stylonurines were comparatively rare and retained their posterior prosomal appendages for walking. Despite their rarity,
44-461: A cohors (plural cohortes ). Some of the plant families still retain the names of Linnaean "natural orders" or even the names of pre-Linnaean natural groups recognized by Linnaeus as orders in his natural classification (e.g. Palmae or Labiatae ). Such names are known as descriptive family names. In the field of zoology , the Linnaean orders were used more consistently. That is,
66-509: 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 ). For some clades covered by
88-570: A distinct rank of biological classification having its own distinctive name (and not just called a higher genus ( genus summum )) was first introduced by the German botanist Augustus Quirinus Rivinus in his classification of plants that appeared in a series of treatises in the 1690s. Carl Linnaeus was the first to apply it consistently to the division of all three kingdoms of nature (then minerals , plants , and animals ) in his Systema Naturae (1735, 1st. Ed.). For plants, Linnaeus' orders in
110-581: A rounded posterior margin to the metastoma and the prosomal appendage III bearing single fixed spines. Brachyopterus is also one of the oldest known genera of eurypterid , being from the Middle Ordovician . The least well-supported group is the Stylonuroidea , containing the problematic genera Stylonurus and Stylonurella , partly due to the incomplete nature of the only known specimen of Stylonurus powriei which does not preserve
132-611: A wide variety of different genera and species. They are all unified by possessing transverse sutures on the ventral plates and lacking a modified podomere 7a on appendage VI. The suborder is divided into four major superfamilies; the Rhenopteroidea , Stylonuroidea , Kokomopteroidea and Mycteropoidea . The most primitive of these, the Rhenopteroidea, includes several previously enigmatic genera, such as Brachyopterus , Kiaeropterus and Rhenopterus , all united by
154-419: 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
176-616: Is the last major radiation of the eurypterids before their extinction in the Permian . Though the Eurypterina contains several famous giant eurypterids such as Pterygotus and Jaekelopterus , the Stylonurina gave rise to large forms as well, several larger than a metre in length. The largest known stylonurine was Hibbertopterus scouleri , with a potential length of almost 2 metres (6 ft 7 in). Stylonurina contains
198-528: The International Code of Zoological Nomenclature , several additional classifications are sometimes used, although not all of these are officially recognized. In their 1997 classification of mammals , McKenna and Bell used two extra levels between superorder and order: grandorder and mirorder . Michael Novacek (1986) inserted them at the same position. Michael Benton (2005) inserted them between superorder and magnorder instead. This position
220-465: The Stylonuroidea and the Mycteropoidea . In both superfamilies, the adaptations to this lifestyle involves modifications to the spines on their anterior prosomal appendages for raking through the substrate of their habitats. Rhenopteroids , kokomopterids and parastylonurids retained primitive prosomal appendages II-IV that were unsuited for sweep-feeding and likely adopted scavenging, whilst
242-815: The Systema Naturae and the Species Plantarum were strictly artificial, introduced to subdivide the artificial classes into more comprehensible smaller groups. When the word ordo was first consistently used for natural units of plants, in 19th-century works such as the Prodromus Systematis Naturalis Regni Vegetabilis of Augustin Pyramus de Candolle and the Genera Plantarum of Bentham & Hooker, it indicated taxa that are now given
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#1732780200826264-567: The hardieopterids may have been benthic bottomdwellers living partially buried in the substrate. Stylonuroids have fixed spines on appendages II-IV which could have been used as dragnets to rake through the sediments and thus entangling anything in their way, whilst the mycteropoids, which have some of the most extreme adaptations, likely were more selective and specialized. Mycteropoids possess modified blades on their anterior prosomal appendages that feature sensory setae. The tactile function of these might have allowed mycteropoids to select prey from
286-412: The anterior prosomal appendages or any details of the ventral structures. Specimens of other members of the group are similarly incomplete, with Stylonurella spinipes not preserving the metastoma or pretelson and telson and Pagea sturrocki not preserving any dorsal structures. The superfamilies Mycteropoidea and Kokomopteroidea are sister groups, united by a median ridge on the carapace between
308-529: The first major and comprehensive analysis of the suborder, which permitted a substantial systematic revision and comparisons to other eurypterid clades. The phylogenetic analysis established that Stylonurina indeed was a monophyletic group composed of four clades: the Rhenopteroidea , Stylonuroidea , Kokomopteroidea and Mycteropoidea . These superfamilies in turn contain the following families (and one genus incertae sedis ): Suborder Stylonurina Diener, 1924 The cladogram presented below showcases
330-417: The lateral eyes and a distal thickening to the podomeres of the prosomal appendages. Though sometimes classified as an order separate from Eurypterida itself, the hibbertopterids are clearly recovered as stylonurine eurypterids in the latest analyses of the group. Strategies for sweep-feeding (raking through the substrate in search of prey) evolved independently in two of the four stylonurine superfamilies,
352-708: The orders in the zoology part of the Systema Naturae refer to natural groups. Some of his ordinal names are still in use, e.g. Lepidoptera (moths and butterflies) and Diptera (flies, mosquitoes, midges, and gnats). In virology , the International Committee on Taxonomy of Viruses 's virus classification includes fifteen taxomomic ranks to be applied for viruses , viroids and satellite nucleic acids : realm , subrealm , kingdom , subkingdom, phylum , subphylum , class, subclass, order, suborder, family, subfamily , genus, subgenus , and species. There are currently fourteen viral orders, each ending in
374-656: The phylogeny of the Stylonurina as presented by Lamsdell et al. (2010). Alkenopterus (here shown as a rhenopterid ) has since been reclassified as a basal eurypterine . Brachyopterus Kiaeropterus Brachyopterella Alkenopterus Rhenopterus Parastylonurus Stylonurella Pagea Stylonurus Laurieipterus Ctenopterus Lamontopterus Kokomopterus Hardieopterus Tarsopterella Hallipterus Drepanopterus Cyrtoctenus Hibbertopterus Woodwardopterus Megarachne Mycterops Suborders What does and does not belong to each order
396-564: The precursor of the currently used International Code of Nomenclature for algae, fungi, and plants . In the first international Rules of botanical nomenclature from the International Botanical Congress of 1905, the word family ( familia ) was assigned to the rank indicated by the French famille , while order ( ordo ) was reserved for a higher rank, for what in the 19th century had often been named
418-502: The rank of family (see ordo naturalis , ' natural order '). In French botanical publications, from Michel Adanson 's Familles naturelles des plantes (1763) and until the end of the 19th century, the word famille (plural: familles ) was used as a French equivalent for this Latin ordo . This equivalence was explicitly stated in the Alphonse Pyramus de Candolle 's Lois de la nomenclature botanique (1868),
440-558: The sediments in a way that stylonuroids could not. Historically, the phylogeny and systematics of the Stylonurina have been far less well understood and less resolved than that of the Eurypterina . Many historical analyses were limited in scope or resolution and the unique hibbertopterids have even on occasion been suggested to be a separate, but closely related, order to Eurypterida, but have lacked an analysis either proving or disproving such an idea. Lamsdell et al . (2011) performed
462-618: The stylonurines have the longest temporal range of the two suborders. The suborder contains some of the oldest known eurypterids, such as Brachyopterus , from the Middle Ordovician as well as the youngest known eurypterids, from the Late Permian . They remained rare throughout the Ordovician and Silurian, though the radiation of the mycteropoids (a group of large sweep-feeding forms) in the Late Devonian and Carboniferous
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#1732780200826484-418: Was adopted by Systema Naturae 2000 and others. In botany , the ranks of subclass and suborder are secondary ranks pre-defined as respectively above and below the rank of order. Any number of further ranks can be used as long as they are clearly defined. The superorder rank is commonly used, with the ending -anae that was initiated by Armen Takhtajan 's publications from 1966 onwards. The order as
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