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97-581: Beipiaosaurus / ˌ b eɪ p j aʊ ˈ s ɔː r ə s / is a genus of therizinosauroid theropod dinosaurs that lived in China during the Early Cretaceous in the Yixian Formation . The first remains were found in 1996 and formally described in 1999. Before the discovery of Yutyrannus , Beipiaosaurus were among the heaviest dinosaurs known from direct evidence to be feathered. Beipiaosaurus

194-438: A pygostyle , three chevrons , an incomplete furcula and scapula , both coracoids , both forelimbs, both ilia , an incomplete pubis , an incomplete ischium , a femur , both tibiae (one incomplete), an incomplete fibula , the astragalus and calcaneum , several tarsals , metatarsals , manual and pedal unguals , and skin impressions of the primitive plumage. The pelvic girdle and caudal vertebrae were discovered during

291-427: A broad arc in either specimen, indicating that they were fairly stiff. They were probably hollow, at least at the base. In 2009 during an interview at Live Science , Xu stated: "Both are definitely not for flight, inferring the function of some structures of extinct animals would be very difficult, and in this case, we are not quite sure whether these feathers are for display or some other functions." He speculated that

388-404: A brownish colouration like those in modern reptiles which fall within the range of dark brownish colourations. Jianchangosaurus is another primitive therizinosaur taxon known from the same formation that was found with impressions of a series of filamentous and unbranched feathers in its holotype specimen. Only the distal ends of the feather impressions are visible and based on their morphology

485-465: A diverse group of insects, and fish such as Lycoptera . Most vertebrates in this formation showed a tendency to become arboreal , including many tree-dwelling birds, and climbing mammals and lizards. The flora was dominated by conifers related to modern species that are found mainly in subtropical and temperate upland forests, with the presence of ferns, cycads, and horsetails. [REDACTED] [REDACTED] Genus The composition of

582-411: A generic three-toed pes instead of four as seen in other members. The exact classification of therizinosaurs had in the past been hotly debated, since their prosauropod -like teeth and body structure indicate that they were generally herbivorous, unlike typical theropods. Beipiaosaurus , being considered to be a primitive therizinosauroid, has features which suggest that all therizinosauroids, including

679-407: 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 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

776-643: 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

873-621: 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,

970-706: A re-excavation of the fossil quarry where the first elements of the holotype were found. These rediscovered elements helped to complete the holotype specimen. A second specimen, STM 31-1 , a partial skeleton, was described by Xu et al. 2009, which preserves a significant covering of unique, elongated feathers. This specimen consisted of a complete skull, a sclerotic ring, the mandible, the atlas and axis bones, nine additional cervical vertebrae, dorsal vertebrae, seventeen cervical ribs, twelve dorsal ribs, both scapulae and coracoids, one complete humerus and proximal humerus, one complete radius and distal radius, one complete ulna and distal ulna, carpals, and some metacarpals. The rear of

1067-409: 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

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1164-505: A secondary coat of much longer, simpler feathers that rose out of the down layer. These unique feathers known as EBFFs (elongated broad filamentous feathers) were first described by Xu et al. 2009, based on specimen STM 31-1 consisting of the torso, head and neck. Xu and his team also found EBFFs in the tail of the holotype IVPP V11559, which were revealed by further preparation. Some of these were damaged during preparation though. The EBFFs differ from other feather types in that they consist of

1261-431: A single, unbranched filament. Most other primitive feathered dinosaurs have down-like feathers made up of two or more filaments branching out from a common base or along a central shaft. The EBFFs of Beipiaosaurus are also much longer than other primitive feather types, measuring about 100–150 mm (10–15 cm) long, roughly half the length of the neck. In Sinosauropteryx , the longest feathers are only about 15% of

1358-427: 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. ;

1455-417: A throwing or serving motion, in order to avoid impingement of the rotator cuff tendons. If the scapula fails to properly elevate the acromion, impingement may occur during the cocking and acceleration phase of an overhead activity. The two muscles most commonly inhibited during this first part of an overhead motion are the serratus anterior and the lower trapezius. These two muscles act as a force couple within

1552-455: 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

1649-596: 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

1746-613: Is known from three reported specimens. Numerous impressions of feather structures were preserved that allowed researchers to determine the feathering color which turned out to be brownish. They were relatively small-sized therizinosaurs, measuring 2.2 m (7.2 ft) long and weighing about 27 kg (60 lb) in contrast to the advanced and giant Segnosaurus or Therizinosaurus . The necks of Beipiaosaurus were shorter than in most therizinosaurs, whose are characterized by elongated necks adapted for high-browsing . Also, their feet configuration differs from therizinosaurids, having

1843-422: Is probable that the detached segment was never united to the rest of the bone . "In terms of comparative anatomy the human scapula represents two bones that have become fused together; the (dorsal) scapula proper and the (ventral) coracoid. The epiphyseal line across the glenoid cavity is the line of fusion. They are the counterparts of the ilium and ischium of the pelvic girdle." The following muscles attach to

1940-460: 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,

2037-474: 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

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2134-733: Is the effect on climate caused by shifts in the tilt of the Earth's axis and by the shape of the Earth's orbit, contributed to the climate fluctuations of this formation. The Yixian Formation is well known for its great diversity of well-preserved specimens and its dinosaurs, such as the tyrannosauroids Dilong and Yutyrannus , the dromaeosaurids Sinornithosaurus , oviraptorosaurs including Caudipteryx , compsognathids including Sinocalliopteryx , avialans including Confuciusornis and some non-theropod dinosaurs, such as Psittacosaurus and Dongbeititan . Other contemporaries of Beipiaosaurus included ancient shrimp, snails and slugs, as well as

2231-400: Is through the anatomical neck of the scapula. The other more common type of fracture is through the surgical neck of the scapula. The surgical neck exits medial to the coracoid process . An abnormally protruding inferior angle of the scapula is known as a winged scapula and can be caused by paralysis of the serratus anterior muscle . In this condition the sides of the scapula nearest

2328-508: The Institute of Vertebrate Paleontology and Paleoanthropology , in Beijing , China. It consists of a partial, sub-adult, skeleton that is largely disarticulated. A significant number of fossilized bones were recovered, including: cranial fragments, a mandible , teeth , three cervical vertebrae , four dorsal vertebrae , four dorsal ribs , two sacral vertebrae , twenty-five caudal vertebrae with

2425-621: 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

2522-799: 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;

2619-401: The glenoid cavity . This plate extends to form the chief part of the bone, the scapular spine growing up from its dorsal surface about the third month. Ossification starts as membranous ossification before birth. After birth, the cartilaginous components would undergo endochondral ossification . The larger part of the scapula undergoes membranous ossification. Some of the outer parts of

2716-419: 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 ,

2813-409: The paleoenvironment of the Yixian Formation involved seasonal climate fluctuations, and was warm and humid, punctuated by dry seasons, in which the environment became more arid. The average yearly temperature during the time of Beipiaosaurus was 10 °C (50 °F), with relatively cold winters for the generally warm Mesozoic era. A study by Wu et al. 2013 concluded that orbital forcing , which

2910-404: 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,

3007-626: The "surprising features in these animals". The holotype ( type specimen ) of Beipiaosaurus inexpectus , IVPP V11559 , was recovered in the Jianshangou Beds of the Yixian Formation in Liaoning Province, China . The specimen was collected in sediment deposited during the Aptian stage of the Early Cretaceous period, approximately 125 million years ago. It is housed in the collection of

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3104-567: The Therizinosauria by Hartman et al. 2019 which is largely based on the data provided by the revision of Zanno in 2010. Beipiaosaurus occupied a more derived position than Falcarius , as previously indicated by Zanno: Falcarius [REDACTED] Jianchangosaurus [REDACTED] Beipiaosaurus [REDACTED] " Chilantaisaurus " zheziangensis Enigmosaurus [REDACTED] Alxasaurus Therizinosauridae [REDACTED] In 2018, McNamara and colleagues discovered

3201-472: The arm. Xu et al. 1999 suggested that these downy feathers represent an intermediate stage between Sinosauropteryx and more advanced birds ( Avialae ). The tail was also covered in feathers between four and seven centimeters long, consisting of parallel filaments with a width of 1.5 mm (0.15 cm), without a trace of pennaceous feathers or a tail fan, as indicated by the preserved pygostyle . Unique among known theropods, Beipiaosaurus also possessed

3298-546: The axillary border, downward and backward, to meet the elevated ridge: to it is attached a fibrous septum which separates the Teres muscles from each other. Its lower third presents a broader, somewhat triangular surface, the inferior angle of the scapula , which gives origin to the Teres major , and over which the Latissimus dorsi glides; frequently the latter muscle takes origin by a few fibers from this part. The acromion forms

3395-442: 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

3492-577: The body being roughly a mirror image of the other. The name derives from the Classical Latin word for trowel or small shovel , which it was thought to resemble. In compound terms, the prefix omo- is used for the shoulder blade in medical terminology. This prefix is derived from ὦμος (ōmos), the Ancient Greek word for shoulder, and is cognate with the Latin (h)umerus , which in Latin signifies either

3589-405: The bone by its arched form, while the summit of the arch serves to support the spine and acromion . The costal surface superior of the scapula is the origin of 1st digitation for the serratus anterior origin. The back of the scapula (also called the dorsal or posterior surface) is arched from above downward, and is subdivided into two unequal parts by the spine of the scapula. The portion above

3686-401: The chest when the arm is abducted. The inferior angle is formed by the union of the medial and lateral borders of the scapula. It is thick and rough and its posterior or back surface affords attachment to the teres major and often to a few fibers of the latissimus dorsi. The anatomical plane that passes vertically through the inferior angle is named the scapular line . The lateral angle of

3783-417: The coracoid bone has fused with the scapula, to become the coracoid process. These changes are associated with the upright gait of mammals, compared with the more sprawling limb arrangement of reptiles and amphibians; the muscles formerly attached to the procoracoid are no longer required. The altered musculature is also responsible for the alteration in the shape of the rest of the scapula; the forward margin of

3880-487: The current official Latin nomenclature, Terminologia Anatomica . Shoulder blade is the colloquial name for this bone. In fish, the scapular blade is a structure attached to the upper surface of the articulation of the pectoral fin , and is accompanied by a similar coracoid plate on the lower surface. Although sturdy in cartilagenous fish , both plates are generally small in most other fish, and may be partially cartilagenous, or consist of multiple bony elements. In

3977-432: The definition by Paul Sereno of this group, Beipiaosaurus is even by definition the basal most member. Lindsay E. Zanno noted that Beipiaosaurus shares a sister-taxon relationship with Falcarius , a taxon that includes all the more derived therizinosauroids, however, it appears to be that Falcarius is more primitive than Beipiaosaurus . The cladogram below is the result of the performed phylogenetic analysis of

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4074-411: The derived therizinosaurid condition may have evolved from a three-toed therizinosauroid ancestor. The head was large relative to other therizinosaurs, with the lower jaw measuring about same length as the femur . The neck appears to be shorter compared to other therizinosaurs. In 2003 the pygostyle , consisting of the fused five last vertebrae of the tail, was described in greater detail, suggesting that

4171-491: The discovery was announced on the famous journal Nature and the type species Beipiaosaurus inexpectus named and described by Xu Xing , Tang Zhilu and Wang Xiaolin . The generic name Beipiaosaurus translates as "Beipiao lizard" after Beipiao , a city in China near the location of its discovery. Beipiaosaurus is known from a single species, B. inexpectus , the specific name , meaning "unexpected" in Latin , referring to

4268-412: The early tetrapods , these two structures respectively became the scapula and a bone referred to as the procoracoid (commonly called simply the " coracoid ", but not homologous with the mammalian structure of that name). In amphibians and reptiles (birds included), these two bones are distinct, but together form a single structure bearing many of the muscle attachments for the forelimb. In such animals,

4365-625: The feathers are considered to be EBFFs, bearing resemblance to those found along the specimens of Beipiaosaurus . These findings suggest that they might have been used for visual display and were common among early therizinosaurs. An evo-devo study published in the year 2003 defined what is a feather. It's stated that the integumentary structures of Beipiaosaurus weren't true feathers, those integumentary structures are filaments that are related to feathers. The affinities of therizinosaurs were originally obscure and often problematic, giving rise to taxonomic debate since they feature similar adaptations to

4462-589: The finer feathers served as an insulatory coat and that the larger feathers were ornamental, perhaps for social interactions such as mating or communication. Li et al. 2014 compared the color and shape of the melanosomes in 181 extant animal specimens, 13 fossil specimens (including Beipiaosaurus ) and previous data about the melanosome diversity using scanning electron microscopes . They found that color in dinosaurs seem to be slightly connected with their physiology. While some species of living reptiles (lizards or crocodiles, which are ectothermic ) have less diversity in

4559-446: 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

4656-482: The fossil dinosaur corneocytes were more densely packed with keratin and lacking lipids (fat), suggesting that Beipiaosaurus and co-analyzed taxa did not get as warm as modern birds, mainly because they were ground-dwelling animals not able to fly. In the case of the primitive birds Confuciusornis , they could not fly at all for long periods. In modern birds these structures, with the addition of fats, help to regulate body temperature during active flight. In addition,

4753-727: The fossilised remains of skin flakes from numerous feathered dinosaurs from the Jehol Biota and some bird species using scanning electron microscope on the preserved feather impressions. The analyzed fossil taxa consisted of Confuciusornis , Beipiaosaurus , Microraptor and Sinornithosaurus . For Beipiaosaurus , the specimen STM 31-1 was analyzed. By exposing the skin flakes under an electron microscope they found corneocytes , which are cells rich in keratin . In order to make comparisons with extant feathered dinosaurs, they analyzed several bird taxa such as Anas , Lonchura and Taeniopygia and found similar cell structures, but

4850-463: The fresh state; and its margins, slightly raised, give attachment to a fibrocartilaginous structure, the glenoidal labrum , which deepens the cavity. At its apex is a slight elevation, the supraglenoid tuberosity , to which the long head of the biceps brachii is attached. The anatomic neck of the scapula is the slightly constricted portion which surrounds the head and is more distinct below and behind than above and in front. The surgical neck of

4947-428: The front edge of the ischium a projection, the obturator process, has a wavy profile with a tip that is curved downwards; the "boot" at the lower end of the ischium has twice the width, measured from the front to the rear, of the lower shaft of the ischium. In 2019 Liao and Xu redescribed the holotype skull in detail, noting new unique cranial traits for Beipiaosaurus . These consisted of the large postorbital joint of

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5044-413: The frontal and its abrupt transition from the orbital edge, a long and keen anterior joint of the parietal, an elongate bottom branching of the squamosal articulation of the parietal, and the deeply external mandibular fenestra that is located towards the rear. Cau (2024) suggested that the contemporary Jianchangosaurus represents a junior synonym of Beipiaosaurus , since the diagnosis distinguishing

5141-727: 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,

5238-399: The glenohumeral joint to properly elevate the acromion process, and if a muscle imbalance exists, shoulder impingement may develop. Other conditions associated with scapular dyskenesis include thoracic outlet syndrome and the related pectoralis minor syndrome . The name scapula as synonym of shoulder blade is of Latin origin. It is commonly used in medical English and is part of

5335-416: The identified corneocytes structures seem to indicate that non-avian dinosaurs had a similar way of shedding skin to extant birds and mammals. Unlike many reptiles alive today ( lizards or snakes ) which shed their skin as a single piece or as several large pieces, Beipiaosaurus and other non-avian dinosaurs shed their skin as dandruff , like Confuciusornis , modern birds or mammals. Studies suggest that

5432-628: 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,

5529-457: 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. Scapula The scapula ( pl. : scapulae or scapulas ), also known as the shoulder blade , is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones, the scapulae are paired, with each scapula on either side of

5626-431: The lower part of the glenoid cavity, and the tip of the coracoid process frequently has a separate nucleus. These various epiphyses are joined to the bone by the 25th year. Failure of bony union between the acromion and spine sometimes occurs (see os acromiale ), the junction being effected by fibrous tissue , or by an imperfect articulation; in some cases of supposed fracture of the acromion with ligamentous union, it

5723-409: The more derived Therizinosauridae , to be coelurosaurian theropods, not sauropodomorph or ornithischian relatives as once believed. In 1996, the peasant Li Yinxian discovered a partial skeleton of a theropod dinosaur near the village of Sihetun . On the following year it was confirmed to have come from the lower beds of the Yixian Formation and represent a single individual. On May 27, 1999,

5820-403: 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

5917-428: 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

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6014-445: The neck area. Beipiaosaurus was a small therizinosaur, measuring 2.2 m (7.2 ft) in length, and before the discovery of Yutyrannus they were the largest dinosaurs known from direct evidence to be feathered. It is estimated to have weighed about 27 kg (60 lb) based on femur length. More advanced therizinosaurids have four functional toes , but the feet of Beipiaosaurus still have reduced inner toes, showing that

6111-437: The neck length. The EBFFs of Beipiaosaurus are also unusually broad, up to 3 mm (0.30 cm) wide in the holotype. The broadest feathers of Sinosauropteryx are only 0.2 mm (0.020 cm) wide, and only slightly wider in larger forms such as Dilong . Additionally, where most primitive feather types are circular in cross section, EBFFs appear to be oval-shaped. None of the preserved EBFFs were curved or bent beyond

6208-405: The original bone became the spine and acromion, from which the main shelf of the shoulder blade arises as a new structure. In dinosaurs the main bones of the pectoral girdle were the scapula (shoulder blade) and the coracoid , both of which directly articulated with the clavicle . The clavicle was present in saurischian dinosaurs but largely absent in ornithischian dinosaurs. The place on

6305-429: The original function of the pygostyle was not linked with pennaceous feathers. According to Zanno in 2010, Beipiaosaurus can be distinguished from other therizinosaur taxa based on the following characteristics, which are unique derived traits ( autapomorphies ): a low ridge is present on the front of the thighbone shaft which extends upwards from the inner condyle; the last four dorsal vertebrae are fused; from at least

6402-526: 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

6499-411: The rest of the bone about the 15th year. Between the 14th and 20th years, the remaining parts ossify in quick succession, and usually in the following order: first, in the root of the coracoid process, in the form of a broad scale; secondly, near the base of the acromion; thirdly, in the inferior angle and contiguous part of the vertebral border; fourthly, near the outer end of the acromion; fifthly, in

6596-424: The ridge is a fibrous septum, which separates the infraspinatus muscle from the Teres major and Teres minor muscles. The upper two-thirds of the surface between the ridge and the axillary border is narrow, and is crossed near its center by a groove for the scapular circumflex vessels; the Teres minor attaches here. The broad and narrow portions above alluded to are separated by an oblique line, which runs from

6693-466: 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 the French botanist Joseph Pitton de Tournefort (1656–1708) is considered "the founder of the modern concept of genera". The scientific name (or

6790-412: The scapula or glenoid angle also known as the head of the scapula is the thickest part of the scapula. It is broad and bears the glenoid fossa on its articular surface which is directed forward, laterally and slightly upwards, and articulates with the head of the humerus . The inferior angle is broader below than above and its vertical diameter is the longest. The surface is covered with cartilage in

6887-448: The scapula passes directly medial to the base of the coracoid process. There are three borders of the scapula: The scapula is ossified from 7 or more centers: one for the body, two for the coracoid process , two for the acromion , one for the vertebral border, and one for the inferior angle. Ossification of the body begins about the second month of fetal life, by an irregular quadrilateral plate of bone forming, immediately behind

6984-420: The scapula (also known as the costal or ventral surface) has a broad concavity called the subscapular fossa , to which the subscapularis muscle attaches. The medial two-thirds of the fossa have 3 longitudinal oblique ridges, and another thick ridge adjoins the lateral border; they run outward and upward. The ridges give attachment to the tendinous insertions, and the surfaces between them to the fleshy fibers, of

7081-417: The scapula are cartilaginous at birth, and would therefore undergo endochondral ossification. At birth, a large part of the scapula is osseous, but the glenoid cavity, the coracoid process, the acromion, the vertebral border and the inferior angle are cartilaginous . From the 15th to the 18th month after birth, ossification takes place in the middle of the coracoid process, which as a rule becomes joined with

7178-434: The scapula include the muscles of the rotator cuff —the subscapularis, teres minor, supraspinatus , and infraspinatus. These muscles attach to the surface of the scapula and are responsible for the internal and external rotation of the shoulder joint , along with humeral abduction. The extrinsic muscles include the biceps , triceps , and deltoid muscles and attach to the coracoid process and supraglenoid tubercle of

7275-399: The scapula is usually a relatively simple plate, lacking the projections and spine that it possesses in mammals. However, the detailed structure of these bones varies considerably in living groups. For example, in frogs, the procoracoid bones may be braced together at the animal's underside to absorb the shock of landing, while in turtles, the combined structure forms a Y-shape in order to allow

7372-410: The scapula to retain a connection to the clavicle (which is part of the shell). In birds, the procoracoids help to brace the wing against the top of the sternum . In the fossil therapsids , a third bone, the true coracoid , formed just behind the procoracoid. The resulting three-boned structure is still seen in modern monotremes , but in all other living mammals, the procoracoid has disappeared, and

7469-405: The scapula, infraglenoid tubercle of the scapula, and spine of the scapula . These muscles are responsible for several actions of the glenohumeral joint. The third group, which is mainly responsible for stabilization and rotation of the scapula, consists of the trapezius , serratus anterior , levator scapulae , and rhomboid muscles . These attach to the medial, superior, and inferior borders of

7566-548: The scapula. The head, processes, and the thickened parts of the bone contain cancellous tissue; the rest consists of a thin layer of compact tissue. The central part of the supraspinatus fossa and the upper part of the infraspinatous fossa , but especially the former, are usually so thin in humans as to be semitransparent; occasionally the bone is found wanting in this situation, and the adjacent muscles are separated only by fibrous tissue. The scapula has two surfaces, three borders, three angles, and three processes. The front of

7663-416: The scapula. The superior angle is located at the approximate level of the second thoracic vertebra . The superior angle of the scapula is thin, smooth, rounded, and inclined somewhat lateralward, and gives attachment to a few fibers of the levator scapulae muscle . The inferior angle of the scapula is the lowest part of the scapula and is covered by the latissimus dorsi muscle . It moves forwards round

7760-403: The scapula: Movements of the scapula are brought about by the scapular muscles. The scapula can perform six actions: Because of its sturdy structure and protected location, fractures of the scapula are uncommon. When they do occur, they are an indication that severe chest trauma has occurred. Scapular fractures involving the neck of the scapula have two patterns. One (rare) type of fracture

7857-408: 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 a species : see Botanical name and Specific name (zoology) . The rules for the scientific names of organisms are laid down in

7954-406: The seventh vertebra onwards the tail vertebrae are fused into a pygostyle; a prominent triangular flange extends outwards, away from the body, from the underside of the first metacarpal ; the skull is large, about as long as the thighbone; the first phalanx of the first digit has a joint surface with the claw, that is elongated in the direction of the finger tip on the outer side of its lower part; on

8051-417: The shape of melanosomes and darker color ranges, some maniraptorans, birds and mammals (which are endothermic ) have an increased diversity of melanosome shapes and more vivid colors. The examined specimen of Beipaosaurus , BMNHC PH000911, preserves feather impressions which are located in the neck area. These are filamentous/sparse in structure and the sampled melanosomes were sphere-shaped and inferred to had

8148-418: The shoulder or the upper arm bone. The scapula forms the back of the shoulder girdle . In humans, it is a flat bone , roughly triangular in shape, placed on a posterolateral aspect of the thoracic cage . The scapula is a thick, flat bone lying on the thoracic wall that provides an attachment for three groups of muscles: intrinsic, extrinsic, and stabilizing and rotating muscles. The intrinsic muscles of

8245-583: The skull of this specimen was badly crushed. Li et al. 2014 mentioned a third specimen labelled under the number BMNHC PH000911 . This specimen hails from the Sihetun locality at the Beipiao County in Liaoning Province and compromises a partial individual preserving the skull (badly crushed), most of the vertebral column, both arms and other postcrania. Traces of feather integument were extensively found around

8342-497: 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,

8439-405: The spine are positioned outward and backward. The appearance of the upper back is said to be wing-like. In addition, any condition causing weakness of the serratus anterior muscle may cause scapular "winging". The scapula plays an important role in shoulder impingement syndrome. Abnormal scapular function is called scapular dyskinesis. The scapula performs elevation of the acromion process during

8536-411: The spine is called the supraspinous fossa , and that below it the infraspinous fossa . The two fossae are connected by the spinoglenoid notch , situated lateral to the root of the spine. There is a ridge on the outer part of the back of the scapula. This runs from the lower part of the glenoid cavity, downward and backward to the vertebral border, about 2.5 cm above the inferior angle. Attached to

8633-412: 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

8730-404: The subscapularis muscle. The lateral third of the fossa is smooth and covered by the fibers of this muscle. At the upper part of the fossa is a transverse depression, where the bone appears to be bent on itself along a line at right angles to and passing through the center of the glenoid cavity , forming a considerable angle, called the subscapular angle; this gives greater strength to the body of

8827-415: The summit of the shoulder, and is a large, somewhat triangular or oblong process, flattened from behind forward, projecting at first laterally, and then curving forward and upward, so as to overhang the glenoid cavity. There are 3 angles: The superior angle of the scapula or medial angle , is covered by the trapezius muscle . This angle is formed by the junction of the superior and medial borders of

8924-466: The taxa was based on ontogenetically variable characters. As such, Jianchangosaurus would represent a less mature individual of Beipiaosaurus . The first feather impressions were found in the holotype specimen, consisting of short, slender filamentous feathers on the left arm. These impressions indicated that the body was predominately covered by downy feather-like fibers, similar to those of Sinosauropteryx , but longer, and oriented perpendicular to

9021-403: 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

9118-608: The unrelated sauropodomorphs and ornithischians . The description of Beipiaosaurus helped to assemble the definitive placement of therizinosaurs within the Theropoda , especially as maniraptorans thanks to the numerous theropod features and irrefutable feather impressions in the holotype. Beipiaosaurus was first assigned to the Therizinosauroidea , in a very primitive position by Xu et al. 1999. All subsequent phylogenetic analyses have confirmed this assignment. According to

9215-566: 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

9312-402: The vertebral border. The base of the acromion is formed by an extension from the spine; the two nuclei of the acromion unite, and then join with the extension from the spine. The upper third of the glenoid cavity is ossified from a separate center (sub coracoid), which appears between the 10th and 11th years and joins between the 16th and the 18th years. Further, an epiphysial plate appears for

9409-429: 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

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