scholarly journals A gigantic bird from the Upper Cretaceous of Central Asia

2011 ◽  
Vol 8 (1) ◽  
pp. 97-100 ◽  
Author(s):  
Darren Naish ◽  
Gareth Dyke ◽  
Andrea Cau ◽  
François Escuillié ◽  
Pascal Godefroit
Keyword(s):  
Phylogenetic Analysis ◽  
Body Size ◽  
Central Asia ◽  
Late Cretaceous ◽  
Upper Cretaceous ◽  
Large Body ◽  
New Taxon ◽  
Ecological Diversity ◽  
Large Body Size ◽  
Fossil Bird

We describe an enormous Late Cretaceous fossil bird from Kazakhstan, known from a pair of edentulous mandibular rami (greater than 275 mm long), which adds significantly to our knowledge of Mesozoic avian morphological and ecological diversity. A suite of autapomorphies lead us to recognize the specimen as a new taxon. Phylogenetic analysis resolves this giant bird deep within Aves as a basal member of Ornithuromorpha. This Kazakh fossil demonstrates that large body size evolved at least once outside modern birds (Neornithes) and reveals hitherto unexpected trophic diversity within Cretaceous Aves.

scholarly journals Systematics of the Rubidgeinae (Therapsida: Gorgonopsia)

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1608 ◽  
Author(s):  
Christian F. Kammerer
Keyword(s):  
South Africa ◽  
Phylogenetic Analysis ◽  
Body Size ◽  
Endemic Species ◽  
Large Body ◽  
Strong Support ◽  
Late Permian ◽  
Large Body Size ◽  
Karoo Basin ◽  
Assemblage Zone

The subfamily Rubidgeinae, containing the largest known African gorgonopsians, is thoroughly revised. Rubidgeinae is diagnosed by the absence of a blade-like parasphenoid rostrum and reduction or absence of the preparietal. Seven rubidgeine species from the Karoo Basin of South Africa are recognized as valid:Aelurognathus tigriceps,Clelandina rubidgei,Dinogorgon rubidgei,Leontosaurus vanderhorsti,Rubidgea atrox,Smilesaurus ferox, andSycosaurus laticeps. Rubidgeines are also present in other African basins:A. tigricepsandS. laticepsoccur in the Upper Madumabisa Mudstone Formation of Zambia, andD. rubidgei,R. atrox, and the endemic speciesRuhuhucerberus haughtonicomb. nov. andSycosaurus nowakicomb. nov. occur in the Usili Formation of Tanzania.Aelurognathus nyasaensisfrom the Chiweta Beds of Malawi also represents a rubidgeine, but of uncertain generic referral pending further preparation. No rubidgeine material is known outside of Africa: the purported Russian rubidgeineLeogorgon klimovensisis not clearly referable to this group and may not be diagnosable. Phylogenetic analysis of rubidgeines reveals strong support for a clade (Rubidgeini) of advanced rubidgeines includingClelandina,Dinogorgon,Leontosaurus, andRubidgea. Support forSmilesaurusas a rubidgeine is weak; it may, as previous authors have suggested, represent an independent evolution of large body size from anArctops-like ancestor. Temporally, rubidgeines are restricted to the Late Permian, first appearing in theTropidostomaAssemblage Zone and reaching highest diversity in theCistecephalusandDaptocephalusassemblage zones of the Beaufort Group.

Late Cretaceous octobrachiate coleoid lower jaws from the north Pacific regions

2008 ◽  
Vol 82 (2) ◽  
pp. 398-408 ◽  
Author(s):  
Kazushige Tanabe ◽  
Pat Trask ◽  
Rick Ross ◽  
Yoshinori Hikida
Keyword(s):  
Late Cretaceous ◽  
North Pacific ◽  
Upper Cretaceous ◽  
Large Body ◽  
Three Dimensional ◽  
New Genera ◽  
Large Body Size ◽  
Diagnostic Features ◽  
The North ◽  
The North Pacific

Eight well-preserved cephalopod jaw fossils were discovered from the Upper Cretaceous (Santonian and Campanian) deposits of Vancouver Island, Canada, and Hokkaido, Japan. They occur individually in calcareous concretions and retain their three-dimensional architecture. Seven of them consist of a widely open outer lamella and a posteriorly projected inner lamella with a pointed rostrum. Both lamellae are made of fluorapatite, which may represent diagenetically altered chitin, and lack a calcareous element. Based on these diagnostic features, the seven jaw fossils are identified as lower jaws of the Coleoidea. Comparison with the lower jaws of modern coleoids allows us to distinguish the following new genera and species among them;Nanaimoteuthis jeletzkyiof the Order Vampyromorphida, andPaleocirroteuthis haggartiandP. pacificaof the Order Cirroctopodida. The lower jaws of these new taxa are clearly distinguished by having a much less projected inner lamella from those of modern and extinct species of the Superorder Decabrachia and the Order Octopodida. The maximum lengths of their outer lamellae (35.0-67.1 mm) are much larger than those of most modern vampyromorph and cirroctopodid species, indicating the large body size and weight of their owners. One of the other three lower jaws examined, characterized by a posteriorly extended outer lamella, may be assigned to the Octopodida. This study clearly demonstrates that large octobrachiate coleoids existed in the Late Cretaceous North Pacific.

scholarly journals The most complete enantiornithine from North America and a phylogenetic analysis of the Avisauridae

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5910 ◽  
Author(s):  
Jessie Atterholt ◽  
J. Howard Hutchison ◽  
Jingmai K. O’Connor
Keyword(s):  
North America ◽  
Late Cretaceous ◽  
New Genus ◽  
Large Body ◽  
Cladistic Analysis ◽  
South American ◽  
New Taxon ◽  
Large Body Size ◽  
First Time ◽  
North And South

The most complete known North American enantiornithine was collected in 1992 but never formally described. The so-called “Kaiparowits avisaurid” remains one of the most exceptional Late Cretaceous enantiornithine fossils. We recognize this specimen as a new taxon, Mirarce eatoni (gen. et sp. nov.), and provide a complete anatomical description. We maintain that the specimen is referable to the Avisauridae, a clade previously only known in North America from isolated tarsometatarsi. Information from this specimen helps to clarify evolutionary trends within the Enantiornithes. Its large body size supports previously observed trends toward larger body mass in the Late Cretaceous. However, trends toward increased fusion of compound elements across the clade as a whole are weak compared to the Ornithuromorpha. The new specimen reveals for the first time the presence of remige papillae in the enantiornithines, indicating this feature was evolved in parallel to dromaeosaurids and derived ornithuromorphs. Although morphology of the pygostyle and (to a lesser degree) the coracoid and manus appear to remain fairly static during the 65 million years plus of enantiornithine evolution, by the end of the Mesozoic at least some enantiornithine birds had evolved several features convergent with the Neornithes including a deeply keeled sternum, a narrow furcula with a short hypocleidium, and ulnar quill knobs—all features that indicate refinement of the flight apparatus and increased aerial abilities. We conduct the first cladistic analysis to include all purported avisuarid enantiornithines, recovering an Avisauridae consisting of a dichotomy between North and South American taxa. Based on morphological observations and supported by cladistic analysis, we demonstrate Avisaurus to be paraphyletic and erect a new genus for “A. gloriae,” Gettyia gen. nov.

A new species of the subgenus Scheloribates (Topobates) (Acari: Oribatida: Scheloribatidae) from Panama

2020 ◽  
Vol 29 (2) ◽  
pp. 278-283
Author(s):  
S.G. Ermilov
Keyword(s):  
New Species ◽  
Body Size ◽  
Leaf Litter ◽  
Related Species ◽  
Large Body ◽  
Oribatid Mite ◽  
Neotropical Region ◽  
Large Body Size ◽  
First Time ◽  
A New Species

The oribatid mite subgenus Scheloribates (Topobates) Grandjean, 1958, is recorded from the Neotropical region for the first time. A new species of this subgenus is described from the leaf litter collected in Cayo Agua Island, Panama. Scheloribates (Topobates) panamaensis sp. nov. differs from its related species by the very large body size and presence of a strong ventrodistal process on the leg femora II–IV.

scholarly journals Atmospheric Hypoxia Limits Selection for Large Body Size in Insects

PLoS ONE ◽  
2009 ◽  
Vol 4 (1) ◽  
pp. e3876 ◽  
Author(s):  
C. Jaco Klok ◽  
Jon F. Harrison
Keyword(s):  
Body Size ◽  
Large Body ◽  
Large Body Size ◽  
Selection For
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