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113-736: Kentrosaurus ( / ˌ k ɛ n t r oʊ ˈ s ɔːr ə s / KEN -troh- SOR -əs ; lit.   ' prickle lizard ' ) is a genus of stegosaurid dinosaur from the Late Jurassic in Lindi Region of Tanzania . The type species is K. aethiopicus , named and described by German palaeontologist Edwin Hennig in 1915. Often thought to be a " primitive " member of the Stegosauria , several recent cladistic analyses find it as more derived than many other stegosaurs, and

226-493: A nomen oblitum , and the junior name declared a nomen protectum . This rule exists primarily to prevent the confusion that would result if a well-known name, with a large accompanying body of literature, were to be replaced by a completely unfamiliar name. An example is the European land snail Petasina edentula ( Draparnaud , 1805). In 2002, researchers found that an older name Helix depilata Draparnaud, 1801 referred to

339-463: A neural arch more than twice as high as the centrum, the vertebral body, and almost completely occupied by the extremely spacious neural canal , a trait unique to Kentrosaurus. The diapophyses too were laterally elongated, creating a Y-shape in anterior view. The sacrum (part of pelvis with vertebrae) consists of 6 fused centra, the first being a loose sacrodorsal, while the rest of the centra's transverse processes (extensions of bone) are fused to

452-557: A species : see Botanical name and Specific name (zoology) . The rules for the scientific names of organisms are laid down in the nomenclature codes , which allow each species a single unique name that, for animals (including protists ), plants (also including algae and fungi ) and prokaryotes ( bacteria and archaea ), is Latin and binomial in form; this contrasts with common or vernacular names , which are non-standardized, can be non-unique, and typically also vary by country and language of usage. Except for viruses ,

565-448: A beak restricted to the jaw tips. Other researchers have interpreted these ridges as modified versions of similar structures in other ornithischians which might have supported fleshy cheeks, rather than beaks. There are two nearly complete braincases known from Kentrosaurus though they exhibit some taphonomic distortion. The frontals and parietals are flat and broad, with the latter bearing two transversely concave ventral sides with

678-401: A behaviour also found in other vertebrates. The problem posed by the ratio is that the multiple specimens studied, died in the same place, but probably not in a sudden mass-death and so do not represent a single herd or contemporary population. The results may have been distorted by a greater chance for robust animals of getting fossilised or discovered. In an earlier study by Galton in 1982, it

791-408: A bone core length of 731 millimetres. The plates have a thickened section in the middle, as if they were modified spines. The spikes and plates were likely covered by horn . Aside from a few exceptions they were not found in close association with other skeletal remains. Thus, the exact position of most osteoderms is uncertain. A pair of closely spaced spikes was found articulated with a tail tip, and

904-420: A browser of low-growing vegetation. This interpretation is supported by the absence of premaxillary teeth and their likely replacement by a horny beak or rhamphotheca . The presence of a beak extended along much of the jaws may have precluded the presence of cheeks in stegosaurs. Due to its phylogenetic position, it is unlikely that Kentrosaurus had an extensive beak like Stegosaurus and it instead probably had

1017-647: A close relative of Stegosaurus from the North American Morrison Formation within the Stegosauridae . Fossils of K. aethiopicus have been found only in the Tendaguru Formation , dated to the late Kimmeridgian and early Tithonian ages, about 152 million years ago . Hundreds of bones were unearthed by German expeditions to German East Africa between 1909 and 1912. Although no complete skeletons are known,

1130-520: A distinct Alcovasaurus : Alcovasaurus Paranthodon Tuojiangosaurus Kentrosaurus Adratiklit Dacentrurus Miragaia Jiangjunosaurus Hesperosaurus Loricatosaurus Stegosaurus Like all ornithischians , Kentrosaurus was a herbivore . The fodder was barely chewed and swallowed in large chunks. One hypothesis on stegosaurid diet holds that they were low-level browsers, eating foliage and low-growing fruit from various non-flowering plants. Kentrosaurus

1243-426: A holotype is not valid, because Hennig's selection has priority. In 2011, Heinrich Mallison clarified that all the material known to Hennig in 1915, i.e. all the bones discovered before 1912, when Hermann Heck concluded the last German excavations, are paralectotypes , and that MB.R.4800 is the correct lectotype. Kentrosaurus was a small stegosaur. It had the typical dinosaurian body bauplan , characterised by

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1356-437: A junior subjective synonym. Objective synonyms are common at the rank of genera, because for various reasons two genera may contain the same type species; these are objective synonyms. In many cases researchers established new generic names because they thought this was necessary or did not know that others had previously established another genus for the same group of species. An example is the genus Pomatia Beck, 1837, which

1469-651: A later homonym of a validly published name is a nomen illegitimum or nom. illeg. ; for a full list refer to the International Code of Nomenclature for algae, fungi, and plants and the work cited above by Hawksworth, 2010. In place of the "valid taxon" in zoology, the nearest equivalent in botany is " correct name " or "current name" which can, again, differ or change with alternative taxonomic treatments or new information that results in previously accepted genera being combined or split. Prokaryote and virus codes of nomenclature also exist which serve as

1582-428: A listing of "synonyms", a "synonymy", often contains designations that for some reason did not make it as a formal name, such as manuscript names, or even misidentifications (although it is now the usual practice to list misidentifications separately ). Although the basic principles are fairly similar, the treatment of synonyms in botanical nomenclature differs in detail and terminology from zoological nomenclature, where

1695-514: A long ilium , did not support the animal alone, and the very robust forelimbs took up 10 to 15% of the bodyweight. The center of mass was not heavily modified by the osteoderms (bony structures in skin) in Kentrosaurus or Stegosaurus , which allowed the animals to stay mobile despite their armament. The hindlimbs’ thigh muscles were very powerful, allowing Kentrosaurus to reach a tripod stance on its hindlegs and tail. Eight specimens from

1808-628: A long time and redescribed as new by a range of subsequent workers, or if a range of genera previously considered separate taxa have subsequently been consolidated into one. For example, the World Register of Marine Species presently lists 8 genus-level synonyms for the sperm whale genus Physeter Linnaeus, 1758, and 13 for the bivalve genus Pecten O.F. Müller, 1776. Within the same kingdom, one generic name can apply to one genus only. However, many names have been assigned (usually unintentionally) to two or more different genera. For example,

1921-419: A number of spikes were found apparently regularly spaced in pairs along the path of an articulated tail. Hennig and Janensch, while grouping the dermal armour elements into four distinct types, recognised an apparently continuous change of shape among them, shorter and flatter plates at the front gradually merging into longer and more pointed spikes towards the rear, suggesting an uninterrupted distribution along

2034-601: A partial humerus, but the anatomy of the humerus is very similar to that of Kentrosaurus and both date to the Late Jurassic. In a phylogenetic analysis, the Chubut stegosaurid was recovered in polytomy with Kentrosaurus as basal stegosaurids, further suggesting that they are closely related. In Hennig's 1915 description, Kentrosaurus was assigned to the family Stegosauridae due to the preservation of dermal armor and features like posterodorsally angled neural spines on

2147-409: A reference for designating currently accepted genus names as opposed to others which may be either reduced to synonymy, or, in the case of prokaryotes, relegated to a status of "names without standing in prokaryotic nomenclature". An available (zoological) or validly published (botanical) name that has been historically applied to a genus but is not regarded as the accepted (current/valid) name for

2260-413: A ridge running down the middle that divides them. The lateral surface of the frontals form part of the orbit (eye socket) and the medial side creates the anterior part of the endocranial cavity (braincase). Basioccipitals (where the skull articulated with the cervical vertebrae) form the posterior floor of the brain and the occipital condyle , which is large and spherical in Kentrosaurus . The rest of

2373-670: A small head, a long neck, short forelimbs and long hindlimbs, and a long, horizontal and muscular tail. Typical stegosaurid traits included the elongation and flatness of the head, the powerful build of the forelimbs, erect and pillar-like hindlimbs and an array of plates and spikes running along both sides of the top mid-line of the animal. Kentrosaurus aethiopicus was a relatively small stegosaur, reaching 4–4.5 m (13–15 ft) in length and 700–1,600 kg (1,500–3,500 lb) in body mass. Some specimens suggest that relatively larger individuals could have existed. These specimens are comparable to some Stegosaurus specimens in terms of

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2486-452: A small, elongated head with a beak used to bite off plant material that would be digested in a large gut. It had a, probably double, row of small plates running down its neck and back. These plates gradually merged into spikes on the hip and tail. The longest spikes were on the tail end and were used to actively defend the animal. There also was a long spike on each shoulder. The thigh bones come in two different types , suggesting that one sex

2599-440: A species is moved to a different genus, a variety is moved to a different species, etc. Synonyms also come about when the codes of nomenclature change, so that older names are no longer acceptable; for example, Erica herbacea L. has been rejected in favour of Erica carnea L. and is thus its synonym. To the general user of scientific names, in fields such as agriculture, horticulture, ecology, general science, etc.,

2712-434: A species, or simple ignorance about an earlier description, may lead a biologist to describe a newly discovered specimen as a new species. A common reason for objective synonyms at this level is the creation of a replacement name. A junior synonym can be given precedence over a senior synonym, primarily when the senior name has not been used since 1899, and the junior name is in common use. The older name may be declared to be

2825-418: A synonym is a name that was previously used as the correct scientific name (in handbooks and similar sources) but which has been displaced by another scientific name, which is now regarded as correct. Thus Oxford Dictionaries Online defines the term as "a taxonomic name which has the same application as another, especially one which has been superseded and is no longer valid". In handbooks and general texts, it

2938-481: A taxon, some of this (including species descriptions, distribution, ecology and more) may well have been published under names now regarded as outdated (i.e., synonyms) and so it is again useful to know a list of historic synonyms which may have been used for a given current (valid) taxon name. Objective synonyms refer to taxa with the same type and same rank (more or less the same taxon, although circumscription may vary, even widely). This may be species-group taxa of

3051-427: A taxon; however, the names published in suppressed works are made unavailable via the relevant Opinion dealing with the work in question. In botany, similar concepts exist but with different labels. The botanical equivalent of zoology's "available name" is a validly published name . An invalidly published name is a nomen invalidum or nom. inval. ; a rejected name is a nomen rejiciendum or nom. rej. ;

3164-455: A total of c. 520,000 published names (including synonyms) as at end 2019, increasing at some 2,500 published generic names per year. "Official" registers of taxon names at all ranks, including genera, exist for a few groups only such as viruses and prokaryotes, while for others there are compendia with no "official" standing such as Index Fungorum for fungi, Index Nominum Algarum and AlgaeBase for algae, Index Nominum Genericorum and

3277-424: A vertebra) and rounded ventral keels. The diapophyses are large and strongly angled posteriorily and parallel to each other. The spinous processes got larger towards the posterior end, while the postzygapophyses became smaller and less horizontal, giving the anterior part of the neck lots of mobility laterally. The dorsal column consists of 13 dorsal (back) vertebrae which are tall and have short centra. They have

3390-482: A very broad base. Because of bone morphology classic reconstructions placed it on the hips, at the iliac blade, while many recent reconstructions place it on the shoulder, because a similarly shaped spike is known to have existed on the shoulder in the Chinese stegosaurs Gigantspinosaurus and Huayangosaurus . Like the spikes and shields of ankylosaurs , the bony plates and spines of stegosaurians evolved from

3503-405: A wedge-shaped proximal end. The manus (hand) was small and had five toes with 2 toes bearing only a single phalange. The hindlimbs were much larger and too are similar to those of other stegosaurs. The femur (thigh bone) is the longest element in the body, with the largest known femur measuring 665 mm from the proximal to distal end. The tibia (shin bone) was wide and robust, while the fibula

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3616-427: Is a synonym. In taxonomy, synonyms are not equals, but have a different status. For any taxon with a particular circumscription , position, and rank, only one scientific name is considered to be the correct one at any given time (this correct name is to be determined by applying the relevant code of nomenclature ). A synonym cannot exist in isolation: it is always an alternative to a different scientific name. Given that

3729-612: Is discouraged by both the International Code of Zoological Nomenclature and the International Code of Nomenclature for algae, fungi, and plants , there are some five thousand such names in use in more than one kingdom. For instance, A list of generic homonyms (with their authorities), including both available (validly published) and selected unavailable names, has been compiled by the Interim Register of Marine and Nonmarine Genera (IRMNG). The type genus forms

3842-413: Is greater than, that of the thigh bone. The caudal (tail) vertebrae are 29 in number, though 27-29 are coossified for attachment to the thagomizers (tail spikes). The caudal vertebrae are unique, as they have a combination of transverse processes up to the 28th vertebra and rod-shaped processes on the posterior caudals. These posterior caudal processes have narrow bases that do not tough the plate formed by

3955-410: Is not correct for the circumscription , position, and rank of the taxon as considered in the particular botanical publication. It is always "a synonym of the correct scientific name", but which name is correct depends on the taxonomic opinion of the author. In botany the various kinds of synonyms are: In botany, although a synonym must be a formally accepted scientific name (a validly published name):

4068-434: Is preserved, with a large crown and long root. The crown notably has fewer marginal denticles and a prominent cingulum compared to Stegosaurus , Tuojiangosaurus , and Huayangosaurus . The neck was composed of 13 cervical (neck) vertebrae, the first being the atlas which was strongly fused to the occipital region of the skull and followed by the axis . The other 11 cervicals had hourglass-shaped centra (the base of

4181-460: Is somewhat arbitrary. Although all species within a genus are supposed to be "similar", there are no objective criteria for grouping species into genera. There is much debate among zoologists about whether enormous, species-rich genera should be maintained, as it is extremely difficult to come up with identification keys or even character sets that distinguish all species. Hence, many taxonomists argue in favor of breaking down large genera. For instance,

4294-474: Is the type species , and the generic name is permanently associated with the type specimen of its type species. Should the specimen turn out to be assignable to another genus, the generic name linked to it becomes a junior synonym and the remaining taxa in the former genus need to be reassessed. In zoological usage, taxonomic names, including those of genera, are classified as "available" or "unavailable". Available names are those published in accordance with

4407-411: Is useful to have synonyms mentioned as such after the current scientific name, so as to avoid confusion. For example, if the much-advertised name change should go through and the scientific name of the fruit fly were changed to Sophophora melanogaster , it would be very helpful if any mention of this name was accompanied by "(syn. Drosophila melanogaster )". Synonyms used in this way may not always meet

4520-621: The International Code of Zoological Nomenclature ; the earliest such name for any taxon (for example, a genus) should then be selected as the " valid " (i.e., current or accepted) name for the taxon in question. Consequently, there will be more available names than valid names at any point in time; which names are currently in use depending on the judgement of taxonomists in either combining taxa described under multiple names, or splitting taxa which may bring available names previously treated as synonyms back into use. "Unavailable" names in zoology comprise names that either were not published according to

4633-824: The International Plant Names Index for plants in general, and ferns through angiosperms, respectively, and Nomenclator Zoologicus and the Index to Organism Names for zoological names. Totals for both "all names" and estimates for "accepted names" as held in the Interim Register of Marine and Nonmarine Genera (IRMNG) are broken down further in the publication by Rees et al., 2020 cited above. The accepted names estimates are as follows, broken down by kingdom: The cited ranges of uncertainty arise because IRMNG lists "uncertain" names (not researched therein) in addition to known "accepted" names;

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4746-529: The Stegosauridae , which lived in the later part of the Jurassic and early Cretaceous, and which were defined by Paul Sereno as all stegosaurians more closely related to Stegosaurus than to Huayangosaurus . This group is widespread, with members across the Northern Hemisphere, Africa and possibly South America . The South American remains come from Chubut , Argentina and consist only of

4859-430: The fair weather wave base and behind siliciclastic and ooid barriers. It appeared to have had little change in salinity levels and experienced tides and storms. The coastal environments consisted of brackish coastal lakes, ponds and pools. These environments had little vegetation and were probably visited by herbivorous dinosaurs mostly during droughts. The well vegetated inlands were dominated by conifers . Overall,

4972-404: The platypus belongs to the genus Ornithorhynchus although George Shaw named it Platypus in 1799 (these two names are thus synonyms ) . However, the name Platypus had already been given to a group of ambrosia beetles by Johann Friedrich Wilhelm Herbst in 1793. A name that means two different things is a homonym . Since beetles and platypuses are both members of the kingdom Animalia,

5085-614: The pterosaur Tendaguripterus recki . Other organisms that inhabited the Tendaguru included corals , echinoderms , cephalopods , bivalves , gastropods , decapods , sharks, neopterygian fish, crocodilians and small mammals like Brancatherulum tendagurensis . Genus The composition of a genus is determined by taxonomists . The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including

5198-451: The specific name aethiopicus to denote the provenance from Africa. Soon after its description, a controversy arose over the stegosaur's name, which is very similar to the ceratopsian Centrosaurus . Under the rules of biological nomenclature, forbidding homonymy , two animals may not be given the same name. Hennig renamed his stegosaur Kentrurosaurus , "pointed-tail lizard", in 1916, while Hungarian paleontologist Franz Nopcsa renamed

5311-473: The French botanist Joseph Pitton de Tournefort (1656–1708) is considered "the founder of the modern concept of genera". The scientific name (or the scientific epithet) of a genus is also called the generic name ; in modern style guides and science, it is always capitalised. It plays a fundamental role in binomial nomenclature , the system of naming organisms , where it is combined with the scientific name of

5424-733: The German Expedition found over 1200 bones of Kentrosaurus , belonging to about fifty individuals, many of which were destroyed during the Second World War. Today, almost all remaining material is housed in the Museum für Naturkunde Berlin (roughly 350 remaining specimens), while the museum of the Institute for Geosciences of the University of Tübingen houses a composite mount, roughly 50% of it being original bones. In

5537-972: The Late Jurassic Tendaguru climate was subtropical to tropical with seasonal rains and pronounced dry periods. During the Early Cretaceous , the Tendaguru became more humid. The Tendaguru Beds are similar to the Morrison Formation of North America except in its marine interbeds. Kentrosaurus would have coexisted with fellow ornithischians like Dysalotosaurus lettowvorbecki ; the sauropods Giraffatitan brancai , Dicraeosaurus hansemanni and D. sattleri , Janenschia africana , Tendaguria tanzaniensis and Tornieria africanus ; theropods " Allosaurus " tendagurensis , "Ceratosaurus" roechlingi , "Torvosaurus" ingens, Elaphrosaurus bambergi , Veterupristisaurus milneri and Ostafrikasaurus crassiserratus ; and

5650-729: The Middle Saurian Beds dating from the upper Kimmeridgian. Some remains were found in the Upper Saurian Beds dating from the Tithonian. Since 2012, the boundary between the Kimmeridgian and Tithonian is dated at 152.1 million year ago. The Tendaguru ecosystem primarily consisted of three types of environment: shallow, lagoon-like marine environments, tidal flats and low coastal environments; and vegetated inland environments. The marine environment existed above

5763-488: The authors have inspected the original material; a . that they take on the responsibility for the act of synonymizing the taxa. The accurate use of scientific names, including synonyms, is crucial in biomedical and pharmacological research involving plants. Failure to use correct botanical nomenclature can lead to ambiguity, hinder reproducibility of results, and potentially cause errors in medicine. Best practices for publication suggest that researchers should provide

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5876-532: The back, a sacrum with five sacral vertebrae and both ilia , both femora and an ulna , and is included in the mounted skeleton at the Museum für Naturkunde in Berlin , Germany . The type locality is Kindope, Tanzania , north of Tendaguru hill. Unaware that Hennig had already defined a lectotype, Peter Galton selected two dorsal vertebrae, specimens MB.R.1930 and MB.R.1931, from the material figured in Hennig's 1915 description, as 'holotypes'. This definition of

5989-413: The back. In addition, the posterior position of the center of mass may not have been advantageous for rapid locomotion, but meant that the animal could quickly rotate around the hips by pushing sideways with the arms, keeping the tail pointed at the attacker. Kentrosaurus was nevertheless not invulnerable. A quick predator could have made it to the tail base (where the impact speed would be much lower) when

6102-442: The base for higher taxonomic ranks, such as the family name Canidae ("Canids") based on Canis . However, this does not typically ascend more than one or two levels: the order to which dogs and wolves belong is Carnivora ("Carnivores"). The numbers of either accepted, or all published genus names is not known precisely; Rees et al., 2020 estimate that approximately 310,000 accepted names (valid taxa) may exist, out of

6215-408: The base of the triceps muscle. The coracoid is sub-circular. The fore limbs were much shorter than the stocky hind limbs, which resulted in an unusual posture. The humerus (upper arm bone), like other stegosaurs, has greatly expanded proximal and distal ends that were attachment points between the coracoid and ulna - radius (forearm bones) respectively. The radius was larger than the ulna and had

6328-419: The beginning of § Zoology . The two are related, with only one word difference between their names.) For example, the scientific name of the red imported fire ant , Solenopsis invicta was published by Buren in 1972, who did not know that this species was first named Solenopsis saevissima wagneri by Santschi in 1916; as there were thousands of publications using the name invicta before anyone discovered

6441-459: The bottom side of the tail vertebrae, have the shape of an inverted T. The scapula (shoulder blade) is sub-rectangular, with a robust blade. Though it is not always perfectly preserved, the acromion ridge is slightly smaller than in Stegosaurus . The blade is relatively straight, although it curves towards the back. There is a small bump on the back of the blade, that would have served as

6554-594: The braincase is formed by the presphenoid composing the anterior end. The overall braincase morphology is very similar to those of Tuojiangosaurus , Huayangosaurus , and Stegosaurus . However, the occipital condyle is a closer distance to the basisphenoid tubera (bone at the front of the braincase) in Kentrosaurus and Huayangosaurus than in Tuojiangosaurus and some specimens of Stegosaurus . Due to dinosaurs having more molding in their braincases, endocasts of Kentrosaurus can be reconstructed using

6667-587: The caudal vertebrae. This is confirmed by modern cladistic analyses, although in 1915 Stegosauridae was a far more inclusive concept that included some taxa now classified as ankylosaurs. A consecutive narrowing down of this concept caused Kentrosaurus , until the 1980s to be seen as a typical "primitive" stegosaurian, to be placed in a more derived, higher, position in the stegosaur evolutionary tree. However, recent analyses have consistently found Kentrosaurus to be in Stegosauridae, though typically as one of

6780-421: The correct name is included among synonyms, although as first among equals it is the "senior synonym": Scientific papers may include lists of taxa, synonymizing existing taxa and (in some cases) listing references to them. The status of a synonym may be indicated by symbols, as for instance in a system proposed for use in paleontology by Rudolf Richter. In that system a v before the year would indicate that

6893-425: The correct name of a taxon depends on the taxonomic viewpoint used (resulting in a particular circumscription, position and rank) a name that is one taxonomist's synonym may be another taxonomist's correct name (and vice versa ). Synonyms may arise whenever the same taxon is described and named more than once, independently. They may also arise when existing taxa are changed, as when two taxa are joined to become one,

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7006-649: The currently accepted binomial with author citation, relevant synonyms, and the accepted family name according to the Angiosperm Phylogeny Group III classification. This practice ensures clear communication, allows proper linking of research to existing literature, and provides insight into phylogenetic relationships that may be relevant to shared chemical constituents or physiological effects. Online databases now make it easy for researchers to access correct nomenclature and synonymy information for plant species. The traditional concept of synonymy

7119-418: The dorsal parts of the sacral ribs into a solid sacral plate. The ribs also fuse to the ilium (the upper part of the pelvis) creating a fully ankylosed and solid sacrum. The ilium is notable in that the preacetabular process, front blade, of the ilium widens laterally, to the front outer side, and does not taper unlike in all other stegosaurs. Another characteristic is that the length of the ilium equals, or

7232-506: The entire body, in fifteen pairs. Because each type of osteoderm was found in mirrored left and right versions, it seems probable that all types of osteoderms were distributed in two rows along the back of the animal, a marked contrast to the better-known North American Stegosaurus , which had one row of plates on the neck, trunk and tail, and two rows of spikes on the tail tip. There is one type of spike that differs from all others in being strongly, and not only slightly, asymmetrical, and having

7345-431: The female staying still in a lordosis posture as the male maneuvers his penis into her cloaca . The shoulder spikes would have made the female unable to lie on her side during mating as is proposed for Stegosaurus . In 2013, a study by Ragna Redelstorff e.a. concluded that the bone histology of Kentrosaurus indicated that it had a higher growth rate than reported for Stegosaurus and Scutellosaurus , in view of

7458-509: The femurs (thighbones) led Holly Barden and Susannah Maidment to realize that Kentrosaurus probably showed sexual dimorphism . This dimorphism of the femurs consisted in them being either more or less robust than the other. The occurrence ratio of the robust morph to the gracile one was 2:1, and it is likely that the higher percentage of animals were females. Because of this ratio, it was considered reasonable to assume that in their society, Kentrosaurus males mated with more than one female,

7571-446: The form "author, year" in zoology, and "standard abbreviated author name" in botany. Thus in the examples above, the genus Canis would be cited in full as " Canis Linnaeus, 1758" (zoological usage), while Hibiscus , also first established by Linnaeus but in 1753, is simply " Hibiscus L." (botanical usage). Each genus should have a designated type , although in practice there is a backlog of older names without one. In zoology, this

7684-478: The fusion of the processes of the sacral vertebrae. Kentrosaurus can be distinguished from other members of the Stegosauria by a number of processes of the vertebrae, which in the tail do not run sub-parallel, as in most dinosaurs. In the front third of the tail, they point backwards, the usual direction. In the middle tail, however, they are almost vertical, and further back they are hook-shaped and point obliquely forward. The chevrons , bones pointing to below from

7797-737: The generic name (or its abbreviated form) still forms the leading portion of the scientific name, for example, Canis lupus lupus for the Eurasian wolf subspecies, or as a botanical example, Hibiscus arnottianus ssp. immaculatus . Also, as visible in the above examples, the Latinised portions of the scientific names of genera and their included species (and infraspecies, where applicable) are, by convention, written in italics . The scientific names of virus species are descriptive, not binomial in form, and may or may not incorporate an indication of their containing genus; for example,

7910-450: The genus Doryphorosaurus , "lance-bearing lizard", the same year. If a renaming had been necessary, Hennig's would have had priority. However, because the spelling is different, both Doryphorosaurus and Kentrurosaurus are unneeded replacement names; Kentrosaurus remains the valid name for the genus with Kentrurosaurus and Doryphorosaurus being its junior objective synonyms . Although no complete individuals were found, some material

8023-402: The ground; thus it could have provided additional support, though precisely because of this flexibility it is not certain whether much support was actually provided: it was not stiff enough to function as a "third leg" as had been suggested by Robert Thomas Bakker . In this pose, Kentrosaurus could have fed at heights of 3.3 m (11 ft). Differences in the proportions, not the size, of

8136-432: The idea that a newly defined genus should fulfill these three criteria to be descriptively useful: Moreover, genera should be composed of phylogenetic units of the same kind as other (analogous) genera. The term "genus" comes from Latin genus , a noun form cognate with gignere ('to bear; to give birth to'). The Swedish taxonomist Carl Linnaeus popularized its use in his 1753 Species Plantarum , but

8249-401: The junior synonym. (Incidentally, this species has since been reclassified and currently resides in the genus Bubo , as Bubo scandiacus ). One basic principle of zoological nomenclature is that the earliest correctly published (and thus available ) name, the senior synonym, by default takes precedence in naming rights and therefore, unless other restrictions interfere, must be used for

8362-633: The largest component, with 23,236 ± 5,379 accepted genus names, of which 20,845 ± 4,494 are angiosperms (superclass Angiospermae). By comparison, the 2018 annual edition of the Catalogue of Life (estimated >90% complete, for extant species in the main) contains currently 175,363 "accepted" genus names for 1,744,204 living and 59,284 extinct species, also including genus names only (no species) for some groups. The number of species in genera varies considerably among taxonomic groups. For instance, among (non-avian) reptiles , which have about 1180 genera,

8475-410: The lizard genus Anolis has been suggested to be broken down into 8 or so different genera which would bring its ~400 species to smaller, more manageable subsets. Junior objective synonym The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently. Unlike synonyms in other contexts, in taxonomy a synonym is not interchangeable with the name of which it

8588-536: The low-keeled osteoderms characteristic of basal thyreophorans. Galton (2019) interpreted plates of an armored dinosaur from the Lower Jurassic ( Sinemurian - Pliensbachian ) Lower Kota Formation of India as fossils of a member of Ankylosauria ; the author argued that this finding indicates a probable early Early Jurassic origin for both Ankylosauria and its sister group Stegosauria. The vast majority of stegosaurian dinosaurs thus far recovered belong to

8701-403: The most (>300) have only 1 species, ~360 have between 2 and 4 species, 260 have 5–10 species, ~200 have 11–50 species, and only 27 genera have more than 50 species. However, some insect genera such as the bee genera Lasioglossum and Andrena have over 1000 species each. The largest flowering plant genus, Astragalus , contains over 3,000 species. Which species are assigned to a genus

8814-454: The most basal genera in the family. Kentrosaurus has many traits not seen in other stegosaurids but seen in basal stegosaurians, such as the presence of a parascapular spine and maxillary teeth with only seven denticles at the margin. The type and sole accepted species of Kentrosaurus is Kentrosaurus aethiopicus , named by Hennig in 1915. Fragmentary fossil material from Wyoming, named Stegosaurus longispinus by Charles Gilmore in 1914,

8927-428: The name could not be used for both. Johann Friedrich Blumenbach published the replacement name Ornithorhynchus in 1800. However, a genus in one kingdom is allowed to bear a scientific name that is in use as a generic name (or the name of a taxon in another rank) in a kingdom that is governed by a different nomenclature code. Names with the same form but applying to different taxa are called "homonyms". Although this

9040-462: The olecranon process in development. The long tail of Kentrosaurus results in a position of the center of mass that is unusually far back for a quadrupedal animal. It rests just in front of the hip, a position usually seen in bipedal dinosaurs. However, the femora are straight in Kentrosaurus , as opposed to typical bipeds, indicating a straight and vertical limb position. Thus, the hindlimbs, though powered by massive thigh muscles attached to

9153-418: The original description, Hennig did not designate a holotype specimen. However, in a detailed monography on the osteology, systematic position and palaeobiology of Kentrosaurus in 1925, Hennig picked the most complete partial skeleton, today inventorised as MB.R.4800.1 through MB.R.4800.37 , as a lectotype (see syntype ). This material includes a nearly complete series of tail vertebrae, several vertebrae of

9266-409: The preserved fossils. The brain is relatively short, deep, and small, with a strong cerebral and pontine flexures and a steeply inclined posterodorsal edge when compared to those of other ornithischians. There is a small dorsal projection in the endocast where an unossified (lacking bone) region between the top of the supraoccipital (bone at the top-back of the braincase) and overlying parietal that

9379-541: The provisions of the ICZN Code, e.g., incorrect original or subsequent spellings, names published only in a thesis, and generic names published after 1930 with no type species indicated. According to "Glossary" section of the zoological Code, suppressed names (per published "Opinions" of the International Commission of Zoological Nomenclature) remain available but cannot be used as the valid name for

9492-493: The relatively rapid deposition of highly vascularised fibrolamellar bone. As Stegosaurus was larger than Kentrosaurus , this contradicts the general rule that larger dinosaurs grew quicker than smaller ones. Because the tail had at least forty caudal vertebrae, it was highly mobile. It could possibly swing at an arc of 180 degrees, covering the entire half circle behind it. Swing speeds at the tail end may have been as high as 50 km/h. Continuous rapid swings would have allowed

9605-614: The remains provided a nearly complete picture of the build of the animal. In the Tendaguru Formation, it coexisted with a variety of dinosaurs such as the carnivorous theropods Elaphrosaurus and Veterupristisaurus , giant herbivorous sauropods Giraffatitan and Tornieria , and the dryosaurid Dysalotosaurus . Kentrosaurus generally measured around 4–4.5 metres (13–15 ft) in length as an adult, and weighed about 700–1,600 kilograms (1,500–3,500 lb). It walked on all fours with straight hindlimbs. It had

9718-469: The rules of nomenclature; as for example when an older name is (re)discovered which has priority over the current name. Speaking in general, name changes for nomenclatural reasons have become less frequent over time as the rules of nomenclature allow for names to be conserved, so as to promote stability of scientific names. In zoological nomenclature, codified in the International Code of Zoological Nomenclature , synonyms are different scientific names of

9831-408: The same taxonomic rank that pertain to that same taxon . For example, a particular species could, over time, have had two or more species-rank names published for it, while the same is applicable at higher ranks such as genera, families, orders, etc. In each case, the earliest published name is called the senior synonym , while the later name is the junior synonym . In the case where two names for

9944-409: The same rank with the same type specimen , genus-group taxa of the same rank with the same type species or if their type species are themselves objective synonyms, of family-group taxa with the same type genus, etc. In the case of subjective synonyms , there is no such shared type, so the synonymy is open to taxonomic judgement, meaning that there is room for debate: one researcher might consider

10057-534: The same species, but this name had never been used after 1899 and was fixed as a nomen oblitum under this rule by Falkner et al. 2002. Such a reversal of precedence is also possible if the senior synonym was established after 1900, but only if the International Commission on Zoological Nomenclature (ICZN) approves an application. (Here the C in ICZN stands for Commission, not Code as it does at

10170-407: The same taxon have been published simultaneously, the valid name is selected accorded to the principle of the first reviser such that, for example, of the names Strix scandiaca and Strix noctua (Aves), both published by Linnaeus in the same work at the same date for the taxon now determined to be the snowy owl , the epithet scandiaca has been selected as the valid name, with noctua becoming

10283-559: The skull, mandible, and teeth have been collected and described from the Tendaguru Formation, most of them being isolated elements. Two quadrates (bones from the jaw joint) were referred to Kentrosaurus , but they instead belong to a juvenile brachiosaurid . The long and narrow skull was small in proportion to the body. It had a small antorbital fenestra , the hole between the nose and eye common to most archosaurs , including modern birds, though lost in extant crocodylians. The skull's low position suggests that Kentrosaurus may have been

10396-497: The specific name particular to the wolf. A botanical example would be Hibiscus arnottianus , a particular species of the genus Hibiscus native to Hawaii. The specific name is written in lower-case and may be followed by subspecies names in zoology or a variety of infraspecific names in botany . When the generic name is already known from context, it may be shortened to its initial letter, for example, C. lupus in place of Canis lupus . Where species are further subdivided,

10509-437: The spikes to slash open the skin of its attacker or to stab the soft tissues and break the ribs or facial bones. More directed blows would have resulted in the sides of the spikes fracturing even sturdy longbones of the legs by blunt trauma. These attacks would have crippled small and medium-sized theropods and may even have done some damage to large ones. Earlier interpretations of the defensive behaviour of Kentrosaurus included

10622-412: The standard format for a species name comprises the generic name, indicating the genus to which the species belongs, followed by the specific epithet, which (within that genus) is unique to the species. For example, the gray wolf 's scientific name is Canis lupus , with Canis ( Latin for 'dog') being the generic name shared by the wolf's close relatives and lupus (Latin for 'wolf') being

10735-493: The strict definitions of the term "synonym" in the formal rules of nomenclature which govern scientific names (see below) . Changes of scientific name have two causes: they may be taxonomic or nomenclatural. A name change may be caused by changes in the circumscription, position or rank of a taxon, representing a change in taxonomic, scientific insight (as would be the case for the fruit fly, mentioned above). A name change may be due to purely nomenclatural reasons, that is, based on

10848-446: The suggestion that the animal might have charged to the rear, to run through attackers with its spines, in the way of modern porcupines . Though Kentrosaurus likely stood with forelimbs erect like in other dinosaurs, it is hypothesised that the animal adopted a sprawling posture when defending itself. Its neck was flexible enough to allow it to keep sight of predators, as it could reach the sides of its body with its snout and look over

10961-401: The synonymy, the ICZN, in 2001, ruled that invicta would be given precedence over wagneri . To qualify as a synonym in zoology, a name must be properly published in accordance with the rules. Manuscript names and names that were mentioned without any description ( nomina nuda ) are not considered as synonyms in zoological nomenclature. In botanical nomenclature , a synonym is a name that

11074-530: The tail passed and the neck and upper-part of the body would have been unprotected by the tail swings. A successful predation of Kentrosaurus may have required group hunting. Compared to the more robust spikes of Stegosaurus , the thinner spikes of Kentrosaurus were at greater risk of bending. Kentrosaurus lived in what is now Tanzania in the Late Jurassic Tendaguru Formation . The main Kentrosaurus quarries were located in

11187-403: The taxon is termed a synonym ; some authors also include unavailable names in lists of synonyms as well as available names, such as misspellings, names previously published without fulfilling all of the requirements of the relevant nomenclatural code, and rejected or suppressed names. A particular genus name may have zero to many synonyms, the latter case generally if the genus has been known for

11300-406: The taxon. However, junior synonyms are still important to document, because if the earliest name cannot be used (for example, because the same spelling had previously been used for a name established for another taxon), then the next available junior synonym must be used for the taxon. For other purposes, if a researcher is interested in consulting or compiling all currently known information regarding

11413-673: The tooth is a typical stegosaurian tooth, small with a widened base and vertical grooves creating five ridges. The dentary has 13 preserved alveoli on the dorsomedial side and they are slightly convex in lateral and dorsal views. On the surface adjacent to the alveoli, there is a shallow groove bearing small foramina (small openings in bone) that is similar to grooves on the dentary of the Cretaceous neornithischian Hypsilophodon , with one foramina per tooth position. Stegosaurian teeth were small, triangular, and flat; wear facets show that they did grind their food. A single complete cheek tooth

11526-479: The two (or more) types to refer to one and the same taxon, another might consider them to belong to different taxa. For example, John Edward Gray published the name Antilocapra anteflexa in 1855 for a species of pronghorn , based on a pair of horns. However, it is now commonly accepted that his specimen was an unusual individual of the species Antilocapra americana published by George Ord in 1815. Ord's name thus takes precedence, with Antilocapra anteflexa being

11639-576: The values quoted are the mean of "accepted" names alone (all "uncertain" names treated as unaccepted) and "accepted + uncertain" names (all "uncertain" names treated as accepted), with the associated range of uncertainty indicating these two extremes. Within Animalia, the largest phylum is Arthropoda , with 151,697 ± 33,160 accepted genus names, of which 114,387 ± 27,654 are insects (class Insecta). Within Plantae, Tracheophyta (vascular plants) make up

11752-429: The virus species " Salmonid herpesvirus 1 ", " Salmonid herpesvirus 2 " and " Salmonid herpesvirus 3 " are all within the genus Salmonivirus ; however, the genus to which the species with the formal names " Everglades virus " and " Ross River virus " are assigned is Alphavirus . As with scientific names at other ranks, in all groups other than viruses, names of genera may be cited with their authorities, typically in

11865-515: Was capable of eating at heights of up to 1.7 m (5 ft 7 in) when on all fours. It may also have been possible for it to rear up on its hindlegs to reach vegetation higher in trees. With its centre of mass close to the hind-limbs, the animal could potentially support itself as it stood up. The hips were likely capable of allowing a vertical trunk rotation of about 60 degrees and the tail probably would either have been fully lifted, not blocking this movement or have enough curvature to rest on

11978-455: Was discovered in association, including a nearly complete tail, hip, several dorsal vertebrae and some limb elements of one individual. These form the core of a mount in the Museum für Naturkunde by Janensch. The mount was dismantled during the museum renovation in 2006/2007, and re-mounted in an improved pose by Research Casting International. Some other material, including a braincase and spine,

12091-545: Was established for a group of terrestrial snails containing as its type species the Burgundy or Roman snail Helix pomatia —since Helix pomatia was already the type species for the genus Helix Linnaeus, 1758, the genus Pomatia was an objective synonym (and useless). On the same occasion, Helix is also a synonym of Pomatia , but it is older and so it has precedence. At the species level, subjective synonyms are common because of an unexpectedly large range of variation in

12204-460: Was in 1993 classified as a North American species of Kentrosaurus , as K. longispinus . However, this action was not accepted by the paleontological community, and S. longispinus has been assigned to its own genus, Alcovasaurus , differing from Kentrosaurus in having more elongated tail spikes and the structure of the pelvis and vertebrae. Cladogram of the phylogenetic analysis of Stegosauridae conducted by Maidment et al (2019), which recovers

12317-632: Was larger and more stout than the other. The first fossils of Kentrosaurus were discovered by the German Tendaguru Expedition in 1909, recognised as belonging to a stegosaur by expedition leader Werner Janensch on 24 July 1910, and described by German palaeontologist Edwin Hennig in 1915. The name Kentrosaurus was coined by Hennig and comes from the Greek kentron / κέντρον , meaning "sharp point" or "prickle", and sauros / σαῦρος meaning "lizard", Hennig added

12430-406: Was likely covered in cartilage . This characteristic is seen in other ornithischians. Because of the prominent flexures, many of the aspects of the brain can only be interpreted by the present structures. In the mandible (lower jaw), only an incomplete right dentary is known from Kentrosaurus . The deep dentary is almost identical in shape to that of Stegosaurus , albeit much smaller. Similarly,

12543-431: Was skinny and thin without a greatly expanded distal end. The pes (foot) terminated in 3 toes, all of which had hoof-like unguals (claws). Typically for a stegosaur, Kentrosaurus had extensive osteoderm (bony structures in the skin) covering, including small plates (probably located on the neck and anterior trunk), and spikes of various shapes. The spikes of Kentrosaurus are very elongated, with one specimen having

12656-424: Was suggested that individual difference in the sacral rib count of both Kentrosaurus and Dacentrurus might be an indication of dimorphism: females would have had an extra pair of sacral ribs, having also the first sacral vertebra connected to the ilium, in addition to the subsequent four sacrals. As the plates and spikes would have been obstacles during copulation, it is possible that pairs mated back-to-back with

12769-553: Was thought to have been misplaced or destroyed during World War II . However, all the supposedly lost cranial material was later found in a drawer of a basement cupboard. From 1909 onwards, Kentrosaurus remains were uncovered in four quarries in the Mittlere Saurierschichten (Middle Saurian Beds) and one quarry in the Obere Saurierschichten (Upper Saurian Beds). During four field seasons,

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