Osteology, paleohistology and phylogenetic relationships of Pellegrinisaurus powelli (Dinosauria: Sauropoda) from the Upper Cretaceous of Argentinean Patagonia

2021 ◽  
pp. 104957
Author(s):  
Ignacio Cerda ◽  
Virginia Laura Zurriaguz ◽  
José Luis Carballido ◽  
Romina González ◽  
Leonardo Salgado
Keyword(s):  
Phylogenetic Relationships ◽  
Upper Cretaceous ◽  
Argentinean Patagonia

Aldebarania arenitea, a new genus and species of Astropectinidae (Asteroidea; Echinodermata) from the Maastrichtian (Upper Cretaceous) Peedee Formation of North Carolina

1995 ◽  
Vol 69 (2) ◽  
pp. 376-380 ◽  
Author(s):  
Daniel B. Blake ◽  
Keith Sturgeon
Keyword(s):  
North Carolina ◽  
Shallow Water ◽  
Phylogenetic Relationships ◽  
Upper Cretaceous ◽  
New Genus ◽  
Water Environment ◽  
New Genus And Species ◽  
Marine Fauna ◽  
Shallow Water Environment

Aldebarania arenitea (Astropectinidae; Asteroidea; Echinodermata) is described from the Rocky Point Member of the Maastrichtian (Upper Cretaceous) Peedee Formation of North Carolina. A turbulent, shallow-water environment is suggested by sedimentary features, a diverse marine fauna, and the morphology of Aldebarania. Aldebarania appears to be a partial ecological equivalent of living Astropecten and Luidia; however, phylogenetic relationships within the Astropectinidae are unstudied and the origin of similarities is unknown.

Description and phylogenetic relationships of a large-bodied sphagesaurid notosuchian from the Upper Cretaceous Adamantina Formation, Bauru Group, São Paulo, southeastern Brazil

2020 ◽  
Vol 106 ◽  
pp. 104259
Author(s):  
Galuber Oliveira Cunha ◽  
Rodrigo Miloni Santucci ◽  
Marco Brandalise de Andrade ◽  
Carlos Eduardo Maia de Oliveira
Keyword(s):  
Phylogenetic Relationships ◽  
Upper Cretaceous ◽  
Sao Paulo ◽  
Southeastern Brazil ◽  
São Paulo ◽  
Bauru Group

Jagtia kunradensis, a new genus and species of clawed lobster (Decapoda: Nephropidae) from the Upper Cretaceous (Upper Maastrichtian) Maastricht Formation, The Netherlands

2000 ◽  
Vol 74 (2) ◽  
pp. 224-229 ◽  
Author(s):  
Dale Tshudy ◽  
Ulf Sorhannus
Keyword(s):  
The Netherlands ◽  
Deep Water ◽  
Phylogenetic Relationships ◽  
Upper Cretaceous ◽  
New Genus ◽  
New Genus And Species ◽  
Type Area ◽  
Fossil Form ◽  
Upper Maastrichtian

A new genus and species of clawed lobster, Jagtia kunradensis, is described from the Upper Cretaceous (Upper Maastrichtian) Kunrade Limestone facies of the Maastricht Formation, The Netherlands. Three nephropid lobster genera and at least three species (Oncopareia bredai Bosquet, 1854, sensu Tshudy, 1993, Oncopareia sp. Tshudy, 1993, Hoploparia beyrichi Schlüter, 1862, and Jagtia kunradensis) have now been collected from limestones of the Maastrichtian type area (southeastern Netherlands and northeastern Belgium). Cladistic methods were employed in re-evaluating the phylogenetic relationships of the nephropid lobsters, including Jagtia. These analyses indicate that Jagtia is part of a clade that includes the recent Thymops and Thymopsis. The new genus is the first fossil form to be closely allied with these deep-water genera.

Sineoamphisbaena hexatabularis, an amphisbaenian (Diapsida: Squamata) from the Upper Cretaceous redbeds at Bayan Mandahu (Inner Mongolia, People's Republic of China), and comments on the phylogenetic relationships of the Amphisbaenia

1996 ◽  
Vol 33 (4) ◽  
pp. 541-577 ◽  
Author(s):  
Xiao-Chun Wu ◽  
Donald B. Brinkman ◽  
Anthony P. Russell
Keyword(s):  
Central Asia ◽  
Phylogenetic Relationships ◽  
Inner Mongolia ◽  
Upper Cretaceous ◽  
Phylogenetic Analyses ◽  
Temporal Region ◽  
People's Republic Of China ◽  
Way Of Life ◽  
Lacustrine Environment ◽  
Republic Of China

Sineoamphisbaena hexatabularis Wu et al., 1993 is the earliest known amphisbaenian represented by well-preserved cranial and postcranial material. It reveals a mosaic of generalized lizard-like features and amphisbaenian characters. Most distinctive of the latter are features of cranial consolidation adaptive for a fossorial way of life. Phylogenetic analyses strongly confirm the monophyly of the Amphisbaenia inclusive of S. hexatabularis. The Amphisbaenia is diagnosed by a suite of apomorphic characters. The available evidence suggests a probable Amphisbaenia–Macrocephalosauridae relationship within the Scincomorpha. This is supported primarily by the unique modifications of the palate and temporal region of the skull. It is argued here that the Amphisbaenia evolved in Central Asia during the Cretaceous, in response to the transition from a perennial lacustrine environment to a dry, semiarid eolian environment. The relatively primitive morphology indicates that S. hexatabularis was not permanently subterranean. The further derived modifications of later forms are associated with tunneling in an environment of more compact soils.

scholarly journals Sea lettuce systematics: lumping or splitting?

2018 ◽  
Author(s):  
Manuela Bernardes Batista ◽  
Regina L. Cunha ◽  
Rita Castilho ◽  
Paulo Antunes Horta
Keyword(s):  
Phylogenetic Relationships ◽  
Upper Cretaceous ◽  
Phylogenetic Analyses ◽  
Brazilian Coast ◽  
Nominal Species ◽  
Bayesian Analyses ◽  
The Pacific ◽  
Phylogenetic Framework ◽  
Flow Through ◽  
Daunting Challenge

AbstractPhylogenetic relationships within sea lettuce species belonging to the genus Ulva is a daunting challenge given the scarcity of diagnostic morphological features and the pervasive phenotypic plasticity. With more than 100 species described on a morphological basis, an accurate evaluation of its diversity is still missing. Here we analysed 277 chloroplast-encoded gene sequences (43 from this study), representing 35 nominal species of Ulva from the Pacific, Indian Ocean, and Atlantic (with a particular emphasis on the Brazilian coast) in an attempt to solve the complex phylogenetic relationships within this widespread genus. Maximum likelihood, Bayesian analyses and species delimitation tests support the existence of 22 evolutionary significant units (ESUs), lumping the currently recognized number of species. All individuals sampled throughout an extensive area of the Brazilian coast were included within two distinct ESUs. Most of the clades retrieved in the phylogenetic analyses do not correspond to a single nominal species. Geographic range evolution indicated that the ancestor of Ulva had a distribution restricted to the temperate North Pacific. The dating analysis estimated its origin during the Upper Cretaceous at 75.8 million years (myr) ago but most of the cladogenetic events within the genus occurred in the last ten myr. Pervasive human-mediated gene flow through ballast water and widespread morphologic plasticity are the most likely explanations for the difficulty in establishing a reliable phylogenetic framework for this conspicuous, widespred and many times abundant green algae morphotype.

Revised morphology of Pycnonemosaurus nevesi Kellner & Campos, 2002 (Theropoda: Abelisauridae) and its phylogenetic relationships

Zootaxa ◽  
2017 ◽  
Vol 4276 (1) ◽  
pp. 1 ◽  
Author(s):  
RAFAEL DELCOURT
Keyword(s):  
Phylogenetic Analysis ◽  
Phylogenetic Relationships ◽  
Upper Cretaceous ◽  
Transverse Process ◽  
Lateral Malleolus ◽  
Caudal Vertebrae ◽  
Initial Description ◽  
Cretaceous Period ◽  
Skeletal Immaturity ◽  
Bauru Group

Abelisaurid theropods were most abundant in the Gondwana during the Cretaceous Period. Pycnonemosaurus nevesi Kellner & Campos, 2002 was the first abelisaurid dinosaur described from the Bauru Group (Brazil, Upper Cretaceous). Nevertheless, its initial description was based on the comparison of a restricted number of remains with other abelisaurids. In this paper, I present a new description of the morphology of Pycnonemosaurus nevesi, including three new caudal transverse processes and a discussion of several new characteristics based on perspectives derived from recently described abelisauroids. Pycnonemosaurus nevesi differs from other abelisaurids based on the following features: a pubis with a small rounded foot and a ventrally-bowed anterior distal end; posterior caudal vertebrae with a hook-shaped transverse process that has an anterodistal expansion that is short and bowed; a strong and massive tibia with a well-developed lateral malleolus that is ventrally expanded. The unfused sutures represent signs of skeletal immaturity, but the specific ontogenetic stage is still uncertain. The current phylogenetic analysis suggests strongly relationship within Pycnonemosaurus and the most-derived abelisaurids (e.g Carnotaurus and Aucasaurus). 

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