scholarly journals Nannofossils, foraminifera and microforaminiferal linings in the Cenozoic diamictites of Cape Lamb, Vega Island, Antarctica

2014 ◽  
Vol 35 (1) ◽  
pp. 1-26 ◽  
Author(s):  
Andrea Concheyro ◽  
Andrea Caramés ◽  
Cecilia R. Amenábar ◽  
Marina Lescano
Keyword(s):  
Early Cretaceous ◽  
Late Cretaceous ◽  
First Record ◽  
Organic Layer ◽  
Sediment Sources ◽  
Lower Maastrichtian ◽  
James Ross Island ◽  
The Antarctic ◽  
Upper Maastrichtian ◽  
Upper Campanian

AbstractMicropaleontological and palynological samples from three Cenozoic diamictites at Cape Lamb, Vega Island, James Ross Basin were analysed. Fossiliferous samples yielded reworked and autochthonous assemblages of Mesozoic calcareous nanno− fossils, impoverished Cretaceous foraminifera together with Neogene species, as well as Late Cretaceous dinoflagellate cysts, pollen, spores and abundant Cenozoic micro− foraminiferal linings. The recovered nannoflora indicates Early Cretaceous (Hauteri− vian-Albian) and Late Cretaceous (Santonian-Early Campanian) ages, suggesting an in− tensive reworking of marine sediments. The presence of the Early Cretaceous species Nannoconus circularis Deres et Acheriteguy in the diamictite represents its first record for the James Ross Basin. The scarce foraminiferal fauna includes Pullenia jarvisi Cushman, which indicates reworking from lower Maastrichtian-lower Paleocene sediments, and also the Neogene autochthonous Trochammina sp. aff. T. intermedia. The in− ner−organic layer observed inside this specimen appears to be identical to microfora− miniferal linings recovered from the same sample. Palynomorphs found in the studied samples suggest erosion from the underlying Snow Hill Island and the Lopez de Bertodano Formation beds (upper Campanian-upper Maastrichtian). These recovered assemblages indicate either different periods of deposition or reworking from diverse sources during Cenozoic glaciation, originating in James Ross Island and the Antarctic Peninsula with the influence of local sediment sources.

scholarly journals First record of Epicymatoceras vaelsense (Nautilida) from the Maastrichtian white chalk of northern Denmark

2018 ◽  
Vol 66 ◽  
pp. 229-235 ◽  
Author(s):  
Oksana Malchyk ◽  
Marcin Machalski
Keyword(s):  
The Netherlands ◽  
Late Cretaceous ◽  
First Record ◽  
The Other ◽  
Northern Germany ◽  
Lower Upper ◽  
Lower Maastrichtian ◽  
C 30 ◽  
Upper Maastrichtian

The atypical Late Cretaceous nautilid Epicymatoceras vaelsense (Binkhorst van den Binkhorst, 1862) is described and illustrated on the basis of three specimens from the Maastrichtian white chalk of Denmark. One of these is probably from the lower/upper Maastrichtian boundary interval at Frejlev, while the other two originate from the uppermost Maastrichtian chalk as exposed in the Dania quarry; both localities are in Jylland, northern Denmark. These are first reports of E. vaelsense from Denmark; the species has previously been recorded from the uppermost Campanian and lower Maastrichtian of the Netherlands, Belgium, northern Germany and Poland. The presence of E. vaelsense in the topmost Maastrichtian white chalk in the Dania quarry is considered the youngest record of Epicymatoceras known to date, suggesting the persistence of the genus until the end of the Cretaceous. The diameter of the embryonic conch of the Danish E. vaelsense may be estimated at c. 30 mm, based on an individual from the Dania quarry, confirming earlier observations that the species possessed one of the largest embryonic conchs amongst Late Cretaceous nautilids.

scholarly journals Discovery of Lebambromyia in Myanmar Cretaceous Amber: Phylogenetic and Biogeographic Implications (Insecta, Diptera, Phoroidea)

Insects ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 354
Author(s):  
Davide Badano ◽  
Qingqing Zhang ◽  
Michela Fratini ◽  
Laura Maugeri ◽  
Inna Bukreeva ◽  
...  
Keyword(s):  
Early Cretaceous ◽  
Late Cretaceous ◽  
Phase Contrast ◽  
First Record ◽  
Geographic Range ◽  
X Ray ◽  
Monophyletic Lineage ◽  
Cladistic Analyses

Lebambromyia sacculifera sp. nov. is described from Late Cretaceous amber from Myanmar, integrating traditional observation techniques and X-ray phase contrast microtomography. Lebambromyia sacculifera is the second species of Lebambromyia after L. acrai Grimaldi and Cumming, described from Lebanese amber (Early Cretaceous), and the first record of this taxon from Myanmar amber, considerably extending the temporal and geographic range of this genus. The new specimen bears a previously undetected set of phylogenetically relevant characters such as a postpedicel sacculus and a prominent clypeus, which are shared with Ironomyiidae and Eumuscomorpha. Our cladistic analyses confirmed that Lebambromyia represented a distinct monophyletic lineage related to Platypezidae and Ironomyiidae, though its affinities are strongly influenced by the interpretation and coding of the enigmatic set of features characterizing these fossil flies.

scholarly journals First record of Calappoidea and Dromioidea from the Upper Cretaceous (Upper Maastrichtian) of NW Madagascar

2003 ◽  
Vol 72 (2-3) ◽  
pp. 135-136
Author(s):  
Alessandro Garassino ◽  
Giovanni Pasini
Keyword(s):  
Late Cretaceous ◽  
Upper Cretaceous ◽  
First Record ◽  
Upper Maastrichtian

The crustaceans from the marine Berivotra Formation, dated as late Cretaceous, from 50 km south of Mahajanga, Madagascar contains macrurans, brachyurans and thalassinideans. Two brachyuran families, Raninidae and Dynomenidae, were previously identified with the genera Notopocorystes, Caloxanthus, Titanocarcinus, Xanthosia, and Dromiopsis. Fragmentary material now also allows the recognition of Dromioidea, Calappoidea and Xanthoidea.

New late Cretaceous (Campanian and Maastrichtian) marine gastropods from California

2003 ◽  
Vol 77 (1) ◽  
pp. 50-63 ◽  
Author(s):  
Richard L. Squires ◽  
Louella R. Saul
Keyword(s):  
New Species ◽  
Upper Cretaceous ◽  
New Genus ◽  
Middle Eocene ◽  
First Record ◽  
Northeastern Brazil ◽  
Marine Gastropods ◽  
The Pacific ◽  
Lower Maastrichtian ◽  
Upper Campanian

Three new genera and six new species of shallow-marine gastropods are named from Upper Cretaceous strata found mainly in California. The trochidsCidarina cretaceanew species andCidarina betanew species, the ficidBulbificopsis garzanew genus and new species, and the cancellariidMataxa aridanew species are from the Maastrichtian part of the Moreno Formation of north-central California. This is the earliest record ofCidarina, whose previous chronologic range was middle Eocene to Recent.Bulbificopsisis the first record of a Cretaceous ficid from the Pacific slope of North America, andMataxawas previously known only from Upper Cretaceous strata in the southeastern United States and northeastern Brazil. The buccinidEripachya jalamanew species and the fasciolariidCalkota daileyinew genus and new species are from the lower upper Campanian Jalama Formation in southern California.Calkotais also recognized herein as occurring in upper Maastrichtian strata of North Dakota and South Dakota. The new melongenid genus,Pentzia, established forFulgur hilgardiWhite, 1889, is from Campanian strata throughout California; middle Campanian strata on Sucia Island, Washington; and upper Campanian to lower Maastrichtian strata in northern Baja California, Mexico.

Monimiaceae sensu lato, an element of Gondwanan polar forests: Evidence from the late Cretaceous-early tertiary wood flora of Antarctica

2001 ◽  
Vol 14 (2) ◽  
pp. 207 ◽  
Author(s):  
Imogen Poole ◽  
Helmut Gottwald
Keyword(s):  
Late Cretaceous ◽  
Upper Cretaceous ◽  
First Record ◽  
Southern South America ◽  
Anatomical Features ◽  
Early Tertiary ◽  
Breadth Ratio ◽  
Ecological Dominance ◽  
Perforation Plates ◽  
The Antarctic

Palaeofloristic studies of the Antarctic Peninsula region are important in furthering our understanding of (i) the radiation and rise to ecological dominance of the angiosperms in the Southern Hemisphere during the Late Cretaceous and (ii) the present day disjunct austral vegetation. Investigations of Upper Cretaceous and Early Tertiary sediments of this region yield a rich assemblage of well-preserved fossil dicotyledonous angiosperm wood which provides evidence for the existence, since the Late Cretaceous, of temperate forests similar in composition to those found in present-day southern South America, New Zealand and Australia. This paper describes two previously unrecognised morphotypes, which can be assigned to the Monimiaceae sensu lato, and represents the first record of this family in the wood flora of Antarctica. Specimens belonging to the first fossil morphotype have been assigned to Hedycaryoxylon SÜss (subfamily Monimioideae) because they exhibit anatomical features characteristic of Hedycaryoxylon and extant Hedycarya J.R.Forst. &amp; G.Forst. and Tambourissa Sonn. Characters include diffuse porosity, vessels which are mainly solitary with scalariform perforation plates, opposite to scalariform intervascular pitting, paratracheal parenchyma, septate fibres and tall (>3 mm), wide multiseriate rays with a length: breadth ratio of approximately 1: 4. Specimens belonging to the second morphotype have been assigned to Atherospermoxylon KrÄusel, erected for fossil woods of the Monimiaceae in the tribe Atherospermeae (now Atherospermataceae) in that they exhibit anatomical features similar to Atherospermoxylon and extant Daphnandra Benth., Doryphora Endl. and Laurelia novae-zelandiae A.Cunn. These characters include diffuse to semi-ring porosity, scalariform perforation plates with up to 25 bars, septate fibres, relatively short (<1 mm) rays with a length: breadth ratio of between 1: 4 and 1: 11.

scholarly journals A new southern Laramidian ankylosaurid, Akainacephalus johnsoni gen. et sp. nov., from the upper Campanian Kaiparowits Formation of southern Utah, USA

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5016 ◽  
Author(s):  
Jelle P. Wiersma ◽  
Randall B. Irmis
Keyword(s):  
Late Cretaceous ◽  
First Record ◽  
Multiple Time ◽  
New Taxon ◽  
Postcranial Skeleton ◽  
Surface Textures ◽  
Close Phylogenetic Relationship ◽  
Biogeographic Provinces ◽  
Dispersal Events ◽  
Upper Campanian

A partial ankylosaurid skeleton from the upper Campanian Kaiparowits Formation of southern Utah is recognized as a new taxon, Akainacephalus johnsoni, gen. et sp. nov. The new taxon documents the first record of an associated ankylosaurid skull and postcranial skeleton from the Kaiparowits Formation. Preserved material includes a complete skull, much of the vertebral column, including a complete tail club, a nearly complete synsacrum, several fore- and hind limb elements, and a suite of postcranial osteoderms, making Akainacephalus johnsoni the most complete ankylosaurid from the Late Cretaceous of southern Laramidia. Arrangement and morphology of cranial ornamentation in Akainacephalus johnsoni is strikingly similar to Nodocephalosaurus kirtlandensis and some Asian ankylosaurids (e.g., Saichania chulsanensis, Pinacosaurus grangeri, and Minotaurasaurus ramachandrani); the cranium is densely ornamented with symmetrically arranged and distinctly raised ossified caputegulae which are predominantly distributed across the dorsal and dorsolateral regions of the nasals, frontals, and orbitals. Cranial caputegulae display smooth surface textures with minor pitting and possess a distinct conical to pyramidal morphology which terminates in a sharp apex. Character analysis suggests a close phylogenetic relationship with N. kirtlandensis, M. ramachandrani, Tarchia teresae, and S. chulsanensis, rather than with Late Cretaceous northern Laramidian ankylosaurids (e.g., Euoplocephalus tutus, Anodontosaurus lambei, and Ankylosaurus magniventris). These new data are consistent with evidence for distinct northern and southern biogeographic provinces in Laramidia during the late Campanian. The addition of this new ankylosaurid taxon from southern Utah enhances our understanding of ankylosaurid diversity and evolutionary relationships. Potential implications for the geographical distribution of Late Cretaceous ankylosaurid dinosaurs throughout the Western Interior suggest multiple time-transgressive biogeographic dispersal events from Asia into Laramidia.

A new abelisauroid theropod from northwestern Patagonia

2006 ◽  
Vol 43 (9) ◽  
pp. 1283-1289 ◽  
Author(s):  
Rodolfo A Coria ◽  
Philip J Currie ◽  
Ariana Paulina Carabajal
Keyword(s):  
Early Cretaceous ◽  
Late Cretaceous ◽  
First Record ◽  
South American ◽  
Middle Section ◽  
Theropod Dinosaur ◽  
Channel Deposits

The Argentinean record of abelisauroid theropods begins in the Early Cretaceous (Ligabueino) and spans most of the Late Cretaceous, from Cenomanian (Ilokelesia, Xenotarsosaurus, and Ekrixinatosaurus) to Campanian–Maastrichtian (Abelisaurus, Carnotaurus, Aucasaurus, and Noasaurus). A fragmentary specimen of a theropod dinosaur was collected in 2000 from the middle section of the Lisandro Formation (Turonian?) at Cerro Bayo Mesa, Neuquén Province, Argentina. The fossil-bearing level, which is part of the Lisandro Formation that also yielded the remains of the basal ornithopod Anabisetia saldiviai, corresponds to a reddish, massive mudstone linked with fluvial channel deposits. The theropod identified as MCF-PVPH-237 is an abelisauroid theropod that increases our knowledge about the evolution of South American Abelisauroidea and is the first record of this clade from the Lisandro Formation.

Late Cretaceous palaeoenvironments and biotas: an Antarctic perspective

1992 ◽  
Vol 4 (4) ◽  
pp. 371-382 ◽  
Author(s):  
J. A. Crame
Keyword(s):  
Late Cretaceous ◽  
High Latitude ◽  
Evolutionary Significance ◽  
Source Regions ◽  
Palynological Assemblages ◽  
James Ross Island ◽  
Extinction Events ◽  
The Antarctic ◽  
Cretaceous Period ◽  
Mass Extinction Events

The Cretaceous period is often regarded as one of "greenhouse" warmth, with perhaps its acme occurring in the late Albian stage (100 Ma ago). However, it is now apparent that, even at this time, there were significant meridional temperature gradients and distinct temperate biotas in the highest latitude regions. This is particularly so in the Southern Hemisphere, where an extensive Albian fossil record from Antarctica, Australia and New Zealand has revealed the presence of austral floras and faunas. With the recent improvements in stratigraphical correlations, it has become possible to trace the later Cretaceous palaeoenvironmental record in the Antarctic Peninsula region. Unfortunately, resolution of the early Late Cretaceous (Cenomanian–Coniacian stages) is still imprecise; there are some indications of strongly differentiated palynological assemblages, but studies of both macrofaunas and palaeotemperature estimates are incomplete. By the Santonian–Campanian, high-latitude biotas are well developed in the James Ross Island region and their enhancement through the final stages of the Cretaceous can be linked to a phase of global cooling. The persistence of low diversity temperate communities in high latitude regions may be of considerable ecological and evolutionary significance. For example, there is evidence to suggest that these communities may have been more resistant to mass extinction events; they may also have been important source regions for replacement taxa that arose after such events.

Probable deinonychosaur tracks from the Upper Cretaceous Wapiti Formation (upper Campanian) of Alberta, Canada

2020 ◽  
pp. 1-14
Author(s):  
Nathan J. Enriquez ◽  
Nicolás E. Campione ◽  
Corwin Sullivan ◽  
Matthew Vavrek ◽  
Robin L. Sissons ◽  
...  
Keyword(s):  
North America ◽  
Early Cretaceous ◽  
Late Cretaceous ◽  
North American ◽  
Upper Cretaceous ◽  
Temporal Window ◽  
Track Record ◽  
Important Addition ◽  
Additional Support ◽  
Upper Campanian

Abstract Late Cretaceous tracks attributable to deinonychosaurs in North America are rare, with only one occurrence of Menglongipus from Alaska and two possible, but indeterminate, occurrences reported from Mexico. Here we describe the first probable deinonychosaur tracks from Canada: a possible trackway and one isolated track on a single horizon from the Upper Cretaceous Wapiti Formation (upper Campanian) near Grande Prairie in Alberta. The presence of a relatively short digit IV differentiates these from argued dromaeosaurid tracks, suggesting the trackmaker was more likely a troodontid. Other noted characteristics of the Wapiti specimens include a rounded heel margin, the absence of a digit II proximal pad impression, and a broad, elliptical digit III. Monodactyl tracks occur in association with the didactyl tracks, mirroring similar discoveries from the Early Cretaceous Epoch of China, providing additional support for their interpretation as deinonychosaurian traces. Although we refrain from assigning the new Wapiti specimens to any ichnotaxon because of their relatively poor undertrack preservation, this discovery is an important addition to the deinonychosaur track record; it helps to fill a poorly represented geographic and temporal window in their known distribution, and demonstrates the presence of a greater North American deinonychosaur ichnodiversity than has previously been recognized.

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