Stratigraphic and taxonomic significance of Tusoteuthis longa Logan (Coleoidea, Teuthida) from the Pembina Member, Pierre Shale (Campanian), of Manitoba

1987 ◽  
Vol 61 (4) ◽  
pp. 727-737 ◽  
Author(s):  
Elizabeth L. Nicholls ◽  
Henry Isaak
Keyword(s):  
Upper Cretaceous ◽  
Taxonomic Significance ◽  
Niobrara Formation ◽  
Pierre Shale ◽  
The Family

The fossilized gladii of six squid from the Pembina Member of the Pierre Shale (Upper Cretaceous, Campanian) of southern Manitoba are referred to Tusoteuthis longa Logan, 1898, a species previously reported only from the Niobrara Formation of Kansas. The characters used to identify the genus are reviewed and it is referred to the family Kelaenidae. Documentation of these specimens extends the range of both the genus and the family to the Campanian of Canada.

scholarly journals Comments on the Pteranodontidae (Pterosauria, Pterodactyloidea) with the description of two new species

2010 ◽  
Vol 82 (4) ◽  
pp. 1063-1084 ◽  
Author(s):  
Alexander W.A. Kellner
Keyword(s):  
New Species ◽  
Sexual Dimorphism ◽  
Individual Variation ◽  
Upper Cretaceous ◽  
Sexually Dimorphic ◽  
Niobrara Formation ◽  
Morphological Variations ◽  
Posterior Process ◽  
Pierre Shale ◽  
Two New Species

Considered one of the best known flying reptiles, Pteranodon has been subject to several reviews in the last century. Found exclusively in the Upper Cretaceous Niobrara Formation and Pierre Shale Group 11 species have been attributed to this genus (excluding the ones presently regarded as representing Nyctosaurus). While reviewers agree that this number is inflated, there is disagreement on how many species can be identified. The last review recognized only two species (Pteranodon longiceps and Pteranodon sternbergi) both being sexually dimorphic. Based on several cranial features, some specimens previously referred to the genus Pteranodon are re-evaluated leading to the recognition of the following species, two of which new that are described here: Pteranodon longiceps, Geosternbergia sternbergi, Geosternbergia maiseyi sp. nov., and Dawndraco kanzai gen. et sp. nov. They differ mainly by features such as the direction and extension of the frontal crest, the angle and extension of the posterior process of the premaxillae, the shape and extension of the lower temporal fenestra and the length and proportion of the rostrum. The procedures to recognize a pterosaur species are also discussed here, and must take into account primarily morphology, in conjunction with stratigraphic and geographic data. Although well aware that changes in morphology not always reflect taxonomy, the lack of stratigraphic data and the limited number of specimens that can be confidently assigned to one species hampers our understanding on the morphological variations as a function of ontogeny, individual variation and sexual dimorphism. Although the present study has not eliminated the possibility to recognize such differences, caution is needed before models are generalized for pterosaurs.

Cassiavellia galtarae, new species, new genus: a new Permian bivalve and its significance for pterioidean systematics

2010 ◽  
Vol 84 (6) ◽  
pp. 1152-1176 ◽  
Author(s):  
Ilya Tëmkin ◽  
John Pojeta
Keyword(s):  
New Species ◽  
New Genus ◽  
Larval Shell ◽  
Upper Permian ◽  
Taxonomic Significance ◽  
New Genus And Species ◽  
The Family ◽  
Dental Ontogeny

An exceptionally well-preserved silicified bivalve from the Upper Permian of Texas is described and assigned to a new genus and species,Cassiavellia galtarae, placed in the family Bakevelliidae. The species represents one of the earliest and best characterized unequivocal occurrences of the multivincular ligament in the superfamily Pterioidea. The silicified material provides a wealth of information on the morphology of inadequately known Paleozoic pterioideans, including hitherto undescribed aspects of the larval shell, auricular sulcus, muscle scars, and dental ontogeny. The discovery of the condyle-fossa complex on the anteroventral shell margin, a feature previously undescibed in Bivalvia, raises the question of the homology and taxonomic significance of the problematic subumbonal ridge-like structures in Pterioidea. In life,C. galtaraewas probably an epifaunal right-pleurothetic bivalve, byssally attached to hard or raised flexible substrata. In addition toC. galtarae, another new species,C. nadkevnae, is placed inCassiavellia.

I.—Description of the Cretaceous Saw-Fish Sclerorhynchus Atavus

1892 ◽  
Vol 9 (12) ◽  
pp. 529-534 ◽  
Author(s):  
Arthur Smith Woodward
Keyword(s):  
Upper Cretaceous ◽  
British Museum ◽  
Systematic Position ◽  
Complex Nature ◽  
The Family

In the “Catalogue of Fossil Fishes in the British Museum“ (pt. i. 1889, p. 76, pl. iii. fig. 1), the imperfect rostrum of a Selachian fish from the Upper Cretaceous of Mount Lebanon was described under the new generic and specific name of Sclerorhynchm atavus. Presenting some resemblances to the rostrum both of the typical saw-fish (Prislis) and of PristiopJtorus, hesitation was expressed in determining the systematic position of the genus to which the fossil pertained; but from the apparently complex nature of the rostral cartilages and the absence of extended prepalatines, it was deemed advisable to place the fish provisionally in the family of Pristidæ.

Fruit developmental biology and endosperm rumination in Elaeocarpus ruminatus (Elaeocarpaceae), and its taxonomic significance

2018 ◽  
Author(s):  
Janet N. Gagul ◽  
David Y. P. Tng ◽  
Darren M. Crayn
Keyword(s):  
Developmental Biology ◽  
Adaptive Significance ◽  
Evolutionary Significance ◽  
Phylogenetic Distribution ◽  
Taxonomic Significance ◽  
The Family ◽  
Developmental Phases ◽  
Trees And Shrubs ◽  
Insight Into ◽  
Gaining Insight

The genus Elaeocarpus is the largest genus in the family Elaeocarpaceae, comprising more than 350 species of trees and shrubs with a mainly Indo-Pacific distribution. Approximately 28 species in the genus, including nine species from Australia, are known to possess ruminate endosperm. To provide a basis for understanding fruit development and endosperm rumination in the genus and, therefore, its taxonomic and evolutionary significance, we studied the fruit anatomy of Elaeocarpus ruminatus F.Muell. at different developmental phases (petal-fall to maturity). We found lignin in pericarp and ovary wall tissues in the earliest stages of development. In contrast, endosperm rumination occurs only after fruits have fully expanded, and becomes more pronounced as fruits ripen. Its phylogenetic distribution suggests that ruminate endosperm is a derived, albeit homoplasious character in Elaeocarpus. Comparative studies on related species will be instructive in determining the utility of ruminate endosperm for informing infra-generic taxonomy of the genus, and gaining insight into its adaptive significance.

Parataxonomic classification of ornithoid eggshell fragments from the Oldman Formation (Judith River Group; Upper Cretaceous), southern Alberta

1996 ◽  
Vol 33 (12) ◽  
pp. 1655-1667 ◽  
Author(s):  
Darla K. Zelenitsky ◽  
L. V. Hills ◽  
Philip J. Currie
Keyword(s):  
Late Cretaceous ◽  
Shell Thickness ◽  
Upper Cretaceous ◽  
Theropod Dinosaur ◽  
Surface Sculpture ◽  
External Zone ◽  
Theropod Dinosaurs ◽  
Southern Alberta ◽  
The Family

Examination of a large number of eggshell fragments collected from the Oldman Formation of southern Alberta reveals a greater ootaxonomic diversity than is known from complete eggs or clutches. Three new oogenera and oospecies of the ornithoid-ratite morphotype and one of the ornithoid-prismatic morphotype are established, based on the eggshell fragments. Porituberoolithus warnerensis oogen. et oosp. nov. and Continuoolithus canadensis oogen. et oosp. nov. have a microstructure similar to that of elongatoolithid eggs of theropod dinosaurs. Tristraguloolithus cracioides oogen. et oosp. nov. and Dispersituberoolithus exilis oogen. et oosp. nov. possess an external zone and thus have a microstructure like modern avian eggshell. Tristraguloolithus has a shell thickness, microstructure, and surface sculpture similar to those of recent bird eggshell of the family Cracidae (order Galliformes). Dispersituberoolithus exhibits the primitive or normal eggshell condition of some recent neognathous avian taxa. The ootaxa described indicate a diversity of both avian and theropod dinosaur egg layers within Devil's Coulee and Knight's Ranch, southern Alberta, during the Late Cretaceous.

The first record of spiral coprolites from the Dinosaur Park Formation (Judith River Group, Upper Cretaceous) southern Alberta, Canada

1995 ◽  
Vol 69 (6) ◽  
pp. 1191-1194 ◽  
Author(s):  
Clive E. Coy
Keyword(s):  
North America ◽  
Upper Cretaceous ◽  
First Record ◽  
Niobrara Formation ◽  
Southern Alberta ◽  
Dinosaur Park Formation

Spiral coprolites from the Upper Cretaceous of North America are poorly known. Enterospirae (fossilized intestines) reported from the Upper Cretaceous Niobrara Formation of western Kansas (Stewart, 1978) were disputed by McAllister (1985), who felt they represented spiral coprolites similar to those described from the Permian by Neumayer (1904). Previously described coprolites from the Upper Cretaceous of Alberta are small, unstructured, ellipsoidal forms thought to derive from a crocodilian or terrestrial, carnivorous reptile of necrophagic or piscivorous habits (Waldman, 1970; Waldman and Hopkins, 1970).

The Cretaceous and Paleocene pleurotomariid (Gastropoda: Vetigastropoda) fauna of Seymour Island, Antarctica

2009 ◽  
Vol 83 (5) ◽  
pp. 750-766 ◽  
Author(s):  
M. G. Harasewych ◽  
Anton Oleinik ◽  
William Zinsmeister
Keyword(s):  
Species Richness ◽  
New Zealand ◽  
South America ◽  
Late Cretaceous ◽  
Upper Cretaceous ◽  
Southern India ◽  
New Combination ◽  
The Family ◽  
The Status ◽  
Seymour Island

Leptomaria antipodensis and Leptomaria hickmanae are described from the Upper Cretaceous [Maastrichtian] Lopez de Bertodano Formation, Seymour Island, and represent the first Mesozoic records of the family Pleurotomariidae from Antarctica. Leptomaria stillwelli, L. seymourensis, Conotomaria sobralensis and C. bayeri, from the Paleocene [Danian], Sobral Formation, Seymour Island, are described as new. Leptomaria larseniana (Wilckens, 1911) new combination, also from the Sobral Formation, is redescribed based on better-preserved material. The limited diversity of the pleurotomariid fauna of Seymour Island is more similar to that of the Late Cretaceous faunas of Australia and New Zealand in terms of the number of genera and species, than to the older, more diverse faunas of South America, southern India, or northwestern Madagascar, supporting the status of the Weddelian Province as a distinct biogeographic unit. The increase in the species richness of this fauna during the Danian may be due to the final fragmentation of Gondwana during this period.

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