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[Ornithology • 2017] Myzomela irianawidodoae • A Colourful New Species of Myzomela Honeyeater from Rote Island in eastern Indonesia ---ScRaBBlE

Myzomela irianawidodoae Prawiradilaga, Baveja, Suparno, Ashari, Ng, Gwee, Verbelen & Rheindt, 2017  photo:   Philippe Verbelen  e-journ...

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Showing posts with label Jehol Biota. Show all posts
Showing posts with label Jehol Biota. Show all posts

Wednesday, March 20, 2019

[PaleoOrnithology • 2017] Exceptional Preservation of Soft Tissue in A New Specimen of Eoconfuciusornis and Its Biological Implications ---ScRaBBlE


Figure 1. Photograph of Eoconfuciusornis indet. STM7-144, preserved in right lateral view; scale bar equals 20 mm
Figure 5. In vivo reconstruction of a male and female pair of Eoconfuciusornis. Artwork by Michael Rothman.


Abstract
We report on an exceptional specimen of Eoconfuciusornis preserving rare soft-tissue traces of the ovary and wing. Ovarian follicles preserve a greater hierarchy than observed in Jeholornis and enantiornithines, suggesting confuciusornithiforms evolved higher rates of yolk deposition in parallel with the neornithine lineage. The preserved soft tissues of the wing indicate the presence of a propatagium and postpatagium, whereas an alular patagium is absent. Preserved remnants of the internal support network of the propatagium bear remarkable similarity to that of living birds. Soft tissue suggests the confuciusornithiform propatagium could maintain a cambered profile and generate lift. The feathers of the wing preserve remnants of their original patterning; however, this is not strongly reflected by observable differences under scanning electron microscopy (SEM). The tail plumage lacks elongate rectrices, suggesting that the earliest known confuciusornithiforms were sexually dimorphic in their plumage.

Keywords: Huajiying, Jehol Biota, Aves, Confuciusornithiformes, propatagium, feathers


Figure 1. (a) Photograph of Eoconfuciusornis indet. STM7-144, preserved in right lateral view; scale bar equals 20 mm.
Inset SEM images (all scale bars equal 2 μm); (b) left-wing coverts (sample 2_2) preserving black eumelanosomes; (c) coronal feathers (sample 2_1) preserving grey eumelanosomes; (d) dark spot of secondaries (sample A) preserving black eumelanosomes; (e) light part of secondaries (sample C) preserving grey mouldic eumelanosomes; (f) tail feathers (sample 2_3) preserving black eumelanosomes; (g) crural feathers (sample 2_4) preserving grey eumelanosomes; (h) submalar feathers (sample G) preserving phaeomelanosomes. Yellow dots indicate location of each sample. 

 

Figure 2. (a) Interpretative drawing of Eoconfuciusornis indet. STM7-144; (b) ovarian follicles; (c) remnants of the internal structure of the propatagium with underlying feathers; (d) preserved pattern in the greater coverts; (e) secondary remiges. Scale bar equals 10 mm in (a) and 5 mm in all insets. Anatomical abbreviations: al, alular metacarpal; ca, caudal vertebrae; ce, cervical vertebrae; cm, carpometacarpus; co, coracoid; cv, wing coverts; de, dentary; dv, dorsal vertebrae; f, frontal; fe, femur; g, gastralia; gc, greater coverts; hu, humerus; il, ilium; is, ischium; l, left; lc, lesser coverts; ma, major metacarpal; mc, marginal coverts; mi, minor metacarpal; mt, metatarsal; p1-3, manual phalanges; pb, pubis; pm, premaxilla; pp, postpatagium; prp, propatagium; py, pygostyle; ra, radius; ri, ribs; s, synsacrum; sc, scapula; sl, scleral ossicles; sr, secondary remiges; st, sternum; tbt, tibiotarsus; tmt, tarsometatarsus; ul, ulna; u, uncinate process. Yellow indicates preserved remnants of maturing ovarian follicles; dermal and epidermal tissue remnants are indicated in tan; remains of collagen fibres are brown. Dark grey indicates body feathers and the dorsal layer of wing coverts; light grey indicates the greater coverts and secondaries with preserved patterning. White dashed boxes represent areas enlarged in insets. 

Figure 5. In vivo reconstruction of a male and female pair of Eoconfuciusornis.
Artwork by Michael Rothman. 

Xiaoting Zheng, Jingmai K. O’Connor, Xiaoli Wang, Yanhong Pan, Yan Wang, Min Wang and Zhonghe Zhou. 2017. Exceptional Preservation of Soft Tissue in A New Specimen of Eoconfuciusornis and Its Biological Implications. National Science Review. nwx004. DOI: 10.1093/nsr/nwx004

Scientists make new discovery about bird evolution
 Summary: A team of scientists has described the most exceptionally preserved fossil bird discovered to date, in a newly published article. The new specimen from the rich Early Cretaceous Jehol Biota (approximately 131 to 120 million years old) is referred to as Eoconfuciusornis, the oldest and most primitive member of the Confuciusornithiformes, a group of early birds characterized by the first occurrence of an avian beak.


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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.

[PaleoOrnithology • 2017] Junornis houi • Flight Aerodynamics in Enantiornithines: Information from A New Chinese Early Cretaceous Bird ---ScRaBBlE


Junornis houi 
Liu, Chiappe, Serrano, Habib, Zhang and Meng, 2017

Abstract

We describe an exquisitely preserved new avian fossil (BMNHC-PH-919) from the Lower Cretaceous Yixian Formation of eastern Inner Mongolia, China. Although morphologically similar to Cathayornithidae and other small-sized enantiornithines from China’s Jehol Biota, many morphological features indicate that it represents a new species, here named Junornis houi. The new fossil displays most of its plumage including a pair of elongated, rachis-dominated tail feathers similarly present in a variety of other enantiornithines. BMNHC-PH-919 represents the first record of a Jehol enantiornithine from Inner Mongolia, thus extending the known distribution of these birds into the eastern portion of this region. Furthermore, its well-preserved skeleton and wing outline provide insight into the aerodynamic performance of enantiornithines, suggesting that these birds had evolved bounding flight—a flight mode common to passeriforms and other small living birds—as early as 125 million years ago.


 


Systematic Paleontology

Aves Linnaeus, 1758  
Pygostylia Chiappe, 2001  
Ornithothoraces Chiappe, 1995  

Enantiornithes Walker, 1981 

Junornis houi gen. et sp. nov.

Fig 1. Slab (BMNHC-PH 919a) (A) and counterslab (BMNHC-PH 919b) (B) of Junornis houi.

Holotype: A nearly complete and articulated skeleton (BMNHC-PH 919; Beijing Museum of Natural History) contained in two slabs (a, b). While the skeleton is preserved as voids of the bony elements, it is surrounded by feather impressions defining the surface of its wings and body outline (Fig 1).

Horizon and locality: Yixian Formation, Early Cretaceous (~ 126±4 mya); Liutiaogou Village, Daming Town, Ningchen County, Inner Mongolia Autonomous Region, China.

Etymology: The generic name Jun is derived from a Chinese character () meaning beautiful; ornis is Greek for bird. The species name, houi honors Dr. Hou Lianhai and his important contributions to Chinese paleornithology.

Diagnosis: A small Cathayornis-like bird distinguishable from other similar enantiornithines by the following combination of characters: rounded craniolateral corner of sternum (more angular in Cathayornis yandica and Houornis caudatus); distinct trough excavating ventral surface of mediocranial portion of sternum; triangular process at base of sternal lateral trabecula (absent in H. caudatus and E. walkeri); sternal lateral trabecula broad (much wider than in C. yandica, E. walkeri, and H. caudatus) and laterally deflected (straight in C. yandica and E. walkeri); sternal intermediate trabecula nearly level with mid-shaft of lateral trabecula (significantly shorter in C. yandica, H. caudatus and E. walkeri); sternal xiphoid process level with lateral trabeculae (trabeculae project further caudal in H. cautus and C. yandica); costal processes of last two penultimate synsacral vertebrae three times wider than same process of last synsacral vertebra; and very broad pelvis.

Conclusions
The discovery of Junornis houi, the first published record of a Jehol enantiornithine from Inner Mongolia Autonomous Region, extends the geographic distribution of these early birds into the eastern portion of this region. The well-preserved wings and overall plumage of BMNHC-PH 919 adds significant information to the poor evidence of wing shape in Enantiornithes. Multiple regressions of skeletal elements and remiges allow estimation of key aerodynamic parameters (aspect ratio and wing loading) for this new enantiornithine. The small size, low aspect ratio, and low wing loading of BMNHC-PH 919 indicate that Junornis houi and other similar enantiornithines could have used bounding as their typical flight mode, especially at high speeds. The general morphology of BMNHC-PH 919 thus supports previous interpretations indicating that most avian flight modes have very ancient origins; bounding flight might have evolved among enantiornithines more than 125 million years ago.


 Di Liu, Luis M. Chiappe, Francisco Serrano, Michael Habib, Yuguang Zhang and Qinjing Meng. 2017. Flight Aerodynamics in Enantiornithines: Information from A New Chinese Early Cretaceous Bird. PLoS ONE. 12(10): e0184637.  DOI: 10.1371/journal.pone.0184637

   

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.

[Paleontology • 2017] Zhongjianosaurus yangi • A New Tiny Dromaeosaurid Dinosaur from the Lower Cretaceous Jehol Group of western Liaoning and Niche Differentiation Among the Jehol Dromaeosaurids ---ScRaBBlE


Zhongjianosaurus yangi 
Xu & Qin, 2017 

Abstract 
The Early Cretaceous Jehol dromaeosaurids are taxonomically and morphologically diverse, and one of them, Microraptor zhaoianus, has been suggested to be among the smallest known non-avialan theropods. However, this idea is based on specimens of relatively early ontogenetic stages, and the lower limit of the mature body mass of Jehol dromaeosaurids thus remains unknown. Here we describe a new dromaeosaurid, Zhongjianosaurus yangi gen. et sp. nov., based on a specimen from the Lower Cretaceous Yixian Formation (the middle section of the Jehol Group) from Sihedang, Lingyuan County, Liaoning in Northeast China. While this new taxon is referable to the Microraptorinae, it differs from other microraptorine dromaeosaurids in numerous features, most notably the fusion of proportionally long uncinate processes to dorsal ribs, a humerus with a strongly medially offset proximal end and a large fenestra within the deltopectoral crest, an ulna slightly longer than the humerus, and an arctometatarsalian pes. Most significantly, the estimated 0.31 kg mass of the Z. yangi holotype of an adult individual confirms that some Jehol dromaeosaurids are among the smallest known non-avialan theropods. Our preliminary analysis demonstrates niche differentiation among the Jehol dromaeosaurids, a phenomenon rarely reported among Mesozoic dinosaurian faunas. 

Key words:  Lower Cretaceous, Jehol Group, Theropoda, Dromaeosauridae, small size, morphological variation, niche differentiation

 

Systematic paleontology

 Theropoda Marsh, 1881
 Tetanurae Gauthier, 1986
 Dromaeosauridae Matthew et Brown, 1922

Zhongjianosaurus yangi gen. et sp. nov.
 Etymology: The genus name and specific epithet are in honor of Yang Zhongjian (C.C. Young), who is the founder of vertebrate paleontology in China.

Locality and Horizon: Sihedang, Lingyuan County, Liaoning Province, China. Possibly Yixian Formation, Aptian, Cretaceous (Swisher et al., 2001).

Diagnosis: A tiny microraptorine theropod distinguishable from other microraptorines in the following autapomorphies: proportionally long ossified uncinate processes fused to dorsal ribs, widely arched furcula with slender and posteriorly curved clavicular rami, humeral proximal end strongly offset medially from humeral shaft, humeral internal tuberosity short, presence of large fenestra within humeral deltopectoral crest, humeral ulnar condyle hypertrophied, ulna slightly longer than humerus, ulnar olecranon process with posterior margin mediolaterally pinched, ulnar distal end bending anteriorly and strongly expanded laterally, proximal end of metacarpal II with strong ventrolateral extension, metacarpal III laterally bowed with longitudinal ventral groove, phalanx II-2 without proximodorsal lip and lacking strong dorsal arching, femoral head stout and lower than trochanteric crest, medial condyle of tibiotarsus distal end with a prominent distal extension, arctometatarsalian pes, and metatarsal II without ginglymus on distal end.

 


 Xing Xu and Zi-Chuan Qin. 2017. A New Tiny Dromaeosaurid Dinosaur from the Lower Cretaceous Jehol Group of western Liaoning and Niche Differentiation Among the Jehol Dromaeosaurids. Vertebrata PalAsiatica. In press.


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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.

[PaleoMammalogy • 2018] Ambolestes zhoui • An Early Cretaceous Eutherian from the Jehol Biota, northeastern China and the Placental–Marsupial Dichotomy ---ScRaBBlE


 Ambolestes zhoui
 Bi, Zheng, Wang, Cignetti, Yang & Wible, 2018


Abstract
Molecular estimates of the divergence of placental and marsupial mammals and their broader clades (Eutheria and Metatheria, respectively) fall primarily in the Jurassic period. Supporting these estimates, Juramaia—the oldest purported eutherian—is from the early Late Jurassic (160 million years ago) of northeastern China. Sinodelphys—the oldest purported metatherian—is from the same geographic area but is 35 million years younger, from the Jehol biota. Here we report a new Jehol eutherianAmbolestes zhoui, with a nearly complete skeleton that preserves anatomical details that are unknown from contemporaneous mammals, including the ectotympanic and hyoid apparatus. This new fossil demonstrates that Sinodelphys is a eutherian, and that postcranial differences between Sinodelphys and the Jehol eutherian Eomaia—previously thought to indicate separate invasions of a scansorial niche by eutherians and metatherians—are instead variations among the early members of the placental lineage. The oldest known metatherians are now not from eastern Asia but are 110 million years old from western North America, which produces a 50-million-year ghost lineage for Metatheria.



Class Mammalia Linnaeus, 1758
Infraclass Eutheria sensu Huxley, 1880

Order incertae sedis
Family incertae sedis

Ambolestes gen. nov.

Ambolestes zhoui sp. nov.

Etymology: Ambo (Latin), both, in reference to the mixture of features previously held to be from eutherians and metatherians; lestes (Greek), robber, a common ending for Cretaceous eutherians. The specific name zhoui is given in reference to Zhonghe Zhou, for his pioneering studies of the Jehol biota.


Shundong Bi, Xiaoting Zheng, Xiaoli Wang, Natalie E. Cignetti, Shiling Yang and John R. Wible. 2018. An Early Cretaceous Eutherian and the Placental–Marsupial Dichotomy. Nature. nature.com/articles/s41586-018-0210-3

Chinese scientists identify new mammal ancestor shine.cn/news/nation/1806146395/

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.

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