Content uploaded by Vertebrata Palasiatica
Author content
All content in this area was uploaded by Vertebrata Palasiatica on Mar 03, 2015
Content may be subject to copyright.
A new genus and species of caudipterid dinosaur from the Lower Cretaceous Jiufotang Formation of western Liaoning, China
Abstract
A new oviraptorosaur, Similicaudipteryx yixianensis gen. et sp. nov. is described from the Jiufotang Formation (120 Ma) of the Jehol Group in western Liaoning, China, which is referred to the Caudipteridae based on a dagger-like pygostyle and the shape of the ilium that are most similar to those of Caudipteryx. It differs from other oviraptorosaurids in that the ratio of pubis to ilium length is 1.46 and the presence of two large and deep hypapophyses on dorsal vertebrae. The known caudipterids have previously been found only from the Jianshangou Member of the Yixian Formation (125 Ma) of the Sihetun area in Liaoning Province. S. yixianensis represents the first caudipterid dinosaur from the Jiufotang Formation. The new discovery provides more information for the discussion of the evolution of oviraptorids during the Early Cretaceous and adds to the dinosaur assemblage of the Jehol Biota.
... In Protarchaeopteryx, metatarsal I is located at the middle shaft of metatarsal II, whereas in Caudipteryx zoui the bone is at about a quarter of the way up the posteromedial corner of metatarsal II (Ji et al., 1998). In Similicaudipteryx and Xingtianosaurus, metatarsal I is located at about one third of the way up the distal end of metatarsal II (He et al., 2008;Qiu et al., 2019). The middle shafts of the three largest metatarsals are straight and tightly appressed. ...
A new small-bodied theropod dinosaur, Migmanychion laiyang gen. et sp. nov., is erected based on appendicular skeletal material from the Lower Cretaceous of the Pigeon Hill locality, Inner Mongolia, China. This theropod shows a peculiar combination of features in the hand, in part shared with therizinosauroids, oviraptorosaurs and with the enigmatic Fukuivenator paradoxus from Japan. Phylogenetic analysis supports the closest affinity of Migmanychion with Fukuivenator, yet alternative placements among Oviraptorosauria or among the non-avialan paravians result suboptimal descriptions of the character distribution. Although this new taxon is confidently referred to Maniraptora, this result is based uniquely on derived features of the hand: only additional material could substantiate its precise placement among the bird-like theropods. Fragmentary appendicular material from the same locality cannot be unambiguously referred to Migmanychion. One specimen, including associated partial pelvis and hindlimbs, is tentatively referred to a paravian maniraptoran.
... Iz ovog perioda postoje nalazi i dinosaura sa perjem koji nisu avijalni poput: Concavenator corcovatus (Carcharodontosauridae) opisan na osnovu skeletnih ostataka pronađenih u Španiji, a koji je ţivio prije oko 130 miliona godina (Ortega et al., 2010); Dilong paradoxus opisanog na osnovu ostataka iz Kine koji je ţivio prije oko 125 miliona godina (Xu et al., 2004), kao i Yutyrannus huali (Xu et al., 2012); Beipiaosaurus inexpectus koji je ţivio prije 124,6 miliona godina, a pronađen je na teritoriji Kine (Xu et al., 1999); Sinocalliopteryx gigas (porodica Compsognathidae) pronađen u Kini koji je ţivio također prije 124,6 miliona godina (Ji et al, 2007); Sinornithosaurus millenii (porodica Dromaeosauridae) koji je ţivio prije 124,5 miliona godina, a opisan je na osnovu ostataka sakupljenih u Kini (Xu et al., 1999); Microraptor zhaoianus i M. hanqingi (Xu et al., 2000;Gong et al., 2012) iz iste porodice koji su ţivjeli prije 120 miliona godina, opisani su na osnovu nalaza iz Kine; Similicaudipteryx yixianensis (Caudipteridae) opisan na osnovu ostataka pronađenih u Kini, ţivjeli su prije između 120-112 miliona godina (He et al., 2008), poznat je po najstarijem obliku karlice nalik pigostilu (Paul, 2010). ...
... In oviraptorosaurians, the manus is well preserved in Caudipteryx spp. while the manus of Similicaudipteryx yixianensis (He et al. 2008) and Xingtianosaurus ganqi (Qiu et al. 2019) are incompletely preserved. In Caudipteryx spp. ...
A well-preserved paravian manus was described from the Jehol Biota of western Liaoning, China. This specimen was inferred as an early-diverging troodontid and reveals new morphological details of the troodontid clade, such as both ends of phalanx II-1 and phalanx II-2 asymmetrical, phalanx II-1 and phalanx III-3 twisted medially, the ventral side of the distal end of phalanx II-2 flat, and the proximal articular surface of phalanx III-1 non-trochoid. The range of motion of this manus was examined based on the CT data of the bones, showing that the range of flexion of this troodontid manus is relatively large while the range of extension is relatively limited, which is consistent with the tendency of the decrease in the manual extension capabilities from early-diverging theropods to maniraptoriforms.
... Fused posteriormost caudals Fused posteriormost caudals is generally known as a shared trait in avialan pygostylians. On the other hand, such feature is also known in the ornithomimosaur Deinocheirus (Lee et al., 2014), therizinosaur Beipiaosaurus (Xu et al., 2003), and oviraptorosaurs Nomingia (Barsbold et al., 2000b), Similicaudipteryx (He et al., 2008), Citipati and Conchoraptor (Persons et al., 2014), as well as the non-pygostylian avialan FIGURE 59. Relationship between olfactory ratio and body mass for selected dinosaurs. Bold and dashed lines represent independent contrast least-squares regression and 95% CI, respectively. ...
A bizarre coelurosaurian theropod Fukuivenator paradoxus is known only from the holotype specimen preserving majority of the skeleton from the Kitadani Dinosaur Quarry of the Lower Cretaceous Kitadani Formation, Tetori Group, Fukui, Japan. With aids of computed tomography techniques, a re-examination of the holotype specimen reveals additional features of Fukuivenator which was unobservable in the original description, such as the presence of parietals and a quadrate, and the fusion of the posteriormost caudal vertebrae. The thorough description in this study results in the emendation of diagnosis including the retraction of the large promaxillary fenestra subequal in size to maxillary fenestra, and the addition of the large maxillary fenestra expanded well dorsally above the suprantral strut. Expansion of morphological information elaborates the phylogenetic dataset, resulting in locating Fukuivenator as an unambiguous member of Maniraptora at the basalmost position of Therizinosauria. This phylogenetic position of Fukuivenator is supported by several therizinosaurian synapomorphies such as the subotic recess on the braincase, 11 cervical vertebrae some of which having two pneumatic foramina, and distal articular condyles on the anterior surface of the humerus. Among numerous diagnostic features, eight characters shared with some non-maniraptoran coelurosaurs and five shared with different clades within Maniraptora, highlighting the notably mosaic condition of Fukuivenator proposed in the original description. The combination of characters for herbivorous and carnivorous diets suggests the omnivory of Fukuivenator, projecting the dietary shift in the earliest evolutionary stage of Therizinosauria. Also, the large olfactory ratio revealed by the revised brain endocast highlights the unusually high olfactory acuity further developed than the plesiomorphic condition, implying that the acute sense of smell might be a characteristic of therizinosaurian theropods.
... Caenagnathids, in contrast, tend to have reduced dorsal and ventral prominences compared to other oviraptorosaurs, although the prominences remain larger than in other theropods. In Chirostenotes pergracilis (TMP 1979.020.0001), the dorsal prominence is enlarged compared to other caenagnathids (Fig. 3E, F; Currie and Russell 1988; Funston 2020), but not to the degree seen in some oviraptorids (e.g., Citipati osmolskae), and in the basal oviraptorosaurs Caudipteryx dongi (Zhou and Wang 2000) and Similicaudipteryx (He et al. 2008). These large prominences in Chirostenotes pergracilis augment the appearance of the constricted "neck" of metatarsal I (Fig. 3E, F). ...
A well-preserved left theropod metatarsal I from the Campanian Mesaverde Formation of Wyoming is described and identified as belonging to a caenagnathid, representing the first occurrence of this clade from the formation. The specimen is unique in being relatively small, but featuring a suite of characters (triangular shaft, relatively minimal constriction between the shaft and the distal condyle, spherical distal condyle) that are seen in larger-bodied caenagnathids such as Anzu wyliei and “Macrophalangia canadensis”. This suggests that the previously-observed differences in metatarsal I morphology between small and large caenagnathids are not solely the result of allometry, but may represent phylogenetically informative variation. This new specimen lends some support to the hypothesis that “Macrophalangia canadensis” does not repre- sent a large Chirostenotes pergracilis. Furthermore, the specimen is important in establishing the presence of caenagnathids within the Mesaverde Formation fauna, in which theropods are rare.
... The origin of birds has been a theme of considerable scientific debate . [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] Currently it is nearly universally accepted that Aves belongs to the derived clade of theropod dinosaurs, the Maniraptora . 18,19 The oviraptorosaur Caudipteryx is a member of this clade and the basal-most maniraptoran with pennaceous feathers . ...
This study seeks to better quantify the parameters that drove the evolution of flight from non-volant winged dinosaurs to modern birds. In order to explore this issue, we used fossil data to model the feathered forelimbs of Caudipteryx, the most basal non-volant maniraptoran dinosaur with elongated pennaceous feathers that could be described as forming proto-wings. In order to quantify the limiting flight factors, we created three hypothetical wing profiles for Caudipteryx with incrementally larger wingspans. We compared them with what revealed through fossils in wing morphology. These four models were analyzed under varying air speed, wing beat amplitude, and wing beat frequency to determine lift, thrust potential, and metabolic requirements. We tested these models using theoretical equations in order to mathematically describe the evolutionary changes observed during the evolution of modern birds from a winged terrestrial theropod like Caudipteryx. Caudipteryx could not fly, but this research indicates that with a large enough wing span, Caudipteryx-like animal could have flown. The results of these analyses mathematically confirm that during the evolution of energetically efficient powered flight in derived maniraptorans, body weight had to decrease and wing area/wing profile needed to increase together with the flapping angle and surface area for the attachment of the flight muscles. This study quantifies the morphological changes that we observe in the pennaraptoran fossil record in the overall decrease in body size in paravians, the increased wing surface area in Archaeopteryx relative to Caudipteryx, and changes observed in the morphology of the thoracic girdle, namely, the orientation of the glenoid and the enlargement of the sternum.
... These diets appear to be linked to forelimb and digit reduction and elongation in each of these genera (figure 6; electronic supplementary material, figure S9), although the sample is small. Interestingly, other caudipterids in which the forelimb is not reduced appear to lack a gastric mill [3,108,109], although this could be the result of taphonomy or other factors. Also, the skulls of derived oviraptorosaurs show numerous correlates of herbivory [8,10,106,110], so retention of a plesiomorphic forelimb seemingly well suited to prey capture does not necessarily reflect strict carnivory. ...
Late Cretaceous trends in Asian dinosaur diversity are poorly understood, but recent discoveries have documented a radiation of oviraptorosaur theropods in China and Mongolia. However, little work has addressed the factors that facilitated this diversification. A new oviraptorid from the Late Cretaceous of Mongolia sheds light on the evolution of the forelimb, which appears to have played a role in the radiation of oviraptorosaurs. Surprisingly, the reduced arm has only two functional digits, highlighting a previously unrecognized occurrence of digit loss in theropods. Phylogenetic analysis shows that the onset of this reduction coincides with the radiation of heyuannine oviraptorids, following dispersal from southern China into the Gobi region. This suggests expansion into a new niche in the Gobi region, which relied less on the elongate, grasping forelimbs inherited by oviraptorosaurs. Variation in forelimb length and manus morphology provides another example of niche partitioning in oviraptorosaurs, which may have made possible their incredible diversity in the latest Cretaceous of Asia.
Important transformations of the pectoral girdle are related to the appearance of flight capabilities in the Dinosauria. Previous studies on this topic focused mainly on paravians yet recent data suggests flight evolved in dinosaurs several times, including at least once among non-avialan paravians. Thus, to fully explore the evolution of flight-related avian shoulder girdle characteristics, it is necessary to compare morphology more broadly. Here, we present information from pennaraptoran specimens preserving pectoral girdle elements, including all purportedly volant taxa, and extensively compare aspects of the shoulder joint. The results show that many pectoral girdle modifications appear during the evolution from basal pennaraptorans to paravians, including changes in the orientation of the coracoid body and the location of the articulation between the furcula and scapula. These modifications suggest a change in forelimb range of motion preceded the origin of flight in paravians. During the evolution of early avialans, additional flight adaptive transformations occur, such as the separation of the scapula and coracoid and reduction of the articular surface between these two bones, reduction in the angle between these two elements, and elongation of the coracoid. The diversity of coracoid morphologies and types of articulations joining the scapula-coracoid suggest that each early avialan lineage evolved these features in parallel as they independently evolved more refined flight capabilities. In early ornithothoracines, the orientation of the glenoid fossa and location of the acrocoracoid approaches the condition in extant birds, suggesting a greater range of motion in the flight stroke, which may represent the acquisition of improved powered flight capabilities, such as ground take-off. The formation of a new articulation between the coracoid and furcula in the Ornithuromorpha is the last step in the formation of an osseous triosseal canal, which may indicate the complete acquisition of the modern flight apparatus. These morphological transitions equipped birds with a greater range of motion, increased and more efficient muscular output and while at the same time transmitting the increased pressure being generated by ever more powerful flapping movements in such a way as to protect the organs. The driving factors and functional adaptations of many of these transitional morphologies are as yet unclear although ontogenetic transitions in forelimb function observed in extant birds provide an excellent framework through which we can explore the behavior of Mesozoic pennaraptorans.
U višegodišnjim zoološkim istraživanjima Bosne i Hercegovine autori, a
posebno kustos ornitolog Dražen Kotrošan, su sakupili i značajan broj podataka o
biodiverzitetu ptica.
Spoznate činjenice, uz konstatacije o brojnim taksonomskim i nomenklaturnim
promjenama date skupine u nizu publiciranih radova dovele su i do specifične
obaveze zvanične aktuelizacije spomenutih podataka, osobito nakon zaključka Vijeća
Odsjeka za biologiju Prirodno-matematičkog fakulteta Univerziteta u Sarajevu da
prof. dr. Suvad Lelo bude odgovorni nastavnik na nastavnom predmetu
(Bio)Sistematika hordata od akademske 2012/2013. godine (na prijedlog
dotadašnjeg odgovornog nastavnika prof. dr. Rifat Škrijelj na čemu mu se i ovom
prilikom javno zahvaljujemo).
Kao zaduženi nastavnik za interpretaciju aktuelne biosistematike ptica dr. Lelo
je oformio ekipu, autore ove knjige, koja je priredila rukopis (skriptu predavanja iz
ornitologije) da bi obezbijedili studenskoj populaciji adekvatan prijegled podataka o
bosanskohercegovačkoj i svjetskoj ornitofauni. Neophodno je istaći da je ovo prva
ornitološka knjiga pripremljena u cilju edukacije studenata biologije od osnivanja
Prirodno-matematičkog fakulteta Univerziteta u Sarajevu, a koja je proistekla od
bosanskohercegovačkih autora. Do sada, skoro pola vijeka, generacije studenata
biologije na Prirodno-matematičkom fakultetu u Sarajevu kao osnovnu literaturu iz
oblasti sistematike kičmenjaka koristile knjigu prof. dr. Aleksandra Aleksopula
„Zoologija kičmenjaka: morfologija, evolucija, ekologija, privredni značaj i sistematika
kičmenjaka“ objavljene 1963. godine u Beogradu.
Na kraju, ovu knjigu posvećujemo najznačajnijem poznavaocu
bosanskohercegovačke ornitofaune, negdašnjem kustosu Zemaljskog muzeja Bosne
i Hercegovine u Sarajevu – Otmaru Reizeru (O. Reiser: 1861.-1936.). O. Rajzer je
kao kustos ornitolog radio od 1887. do 1914. godine pri čemu je utemeljio
bosanskohercegovačku ornitologiju.
An unabated surge of new and important discoveries continues to transform knowledge of pen-naraptoran biology and evolution amassed over the last 150+ years. This chapter summarizes progress made thus far in sampling the pennaraptoran fossil record of the Mesozoic and Paleocene and proposes priority areas of attention moving forward. Oviraptorosaurians are bizarre, nonparavian pennaraptorans first discovered in North America and Mongolia within Late Cretaceous rocks in the early 20th century. We now know that oviraptorosaurians also occupied the Early Cretaceous and their unquestionable fossil record is currently limited to Laurasia. Early Cretaceous material from China preserves feathers and other soft tissues and ingested remains including gastroliths and other stomach contents, while brooding specimens and age-structured, single-species accumulations from China and Mongolia provide spectacular behavioral insights. Less specialized early oviraptorosaurians like Incisivosaurus and Microvenator remain rare, and ancestral forms expected in the Late Jurassic are yet to be discovered, although some authors have suggested Epidexipteryx and possibly other scansoriopterygids may represent early-diverging oviraptorosaurians. Long-armed scansoriopterygids from the Middle-Late Jurassic of Laurasia are either early-diverging oviraptorosaurians or paravians, and some have considered them to be early-diverging avialans. Known from five (or possibly six) feathered specimens from China, only two mature individuals exist, representing these taxa. These taxa, Yi and Ambopteryx, preserve stylopod-supported wing membranes that are the only known alternative to the feathered, muscular wings that had been exclusively associated with dinosaurian flight. Thus, scansoriopterygid specimens-particularly those preserving soft tissue-remain a key priority for future specimen collection. Dromaeosaurids and troodontids were first discovered in North America and Mongolia in Late Cretaceous rocks. More recent discoveries show that these animals originated in the Late Jurassic, were strikingly feathered, lived across diverse climes and environments, and at least in the case of dromaeosaurids, attained a global distribution and the potential for aerial locomotion at small size.
ResearchGate has not been able to resolve any references for this publication.