scholarly journals EVIDENCE FOR GONDWANAN ORIGINS FOR SASSAFRAS (LAURACEAE)? LATE CRETACEOUS FOSSIL WOOD OF ANTARCTICA

IAWA Journal ◽  
2000 ◽  
Vol 21 (4) ◽  
pp. 463-475 ◽  
Author(s):  
Imogen Poole ◽  
Hans G. Richter ◽  
Jane E. Francis
Keyword(s):  
New Species ◽  
North America ◽  
East Asia ◽  
Late Cretaceous ◽  
Fossil Wood ◽  
New Taxon ◽  
Parent Plant ◽  
The Past ◽  
Vessel Elements ◽  
Perforation Plates

Sassafrasoxylon gottwaldii sp. nov. is a new taxon for fossil wood with a suite of features diagnostic of Sassafras Nees & Eberm. of the Lauraceae. The fossil wood described is from Late Cretaceous (Santonian- Maastrichtian) sediments of the northern Antarctica Peninsula region. This new species of Sassafrasoxylon Brezinová et Süss resembles the species of extant Sassafras in being distinctly ring-porous, having vessel elements with simple perforation plates and very occasional scalariform plates with relatively few bars in the narrowest latewood vessels, alternate intervascular pitting, marginal (initial) parenchyma bands and paratracheal vasicentric parenchyma in the latewood, multiseriate rays and oil and /or mucilage cells. The fossils were found as isolated pieces of wood and therefore it is not certain whether the parent plant was Sassafras-like in all characters. Consequently the fossils have been placed in an organ genus rather than in extant Sassafras. This is the oldest record of an organ with features closest to extant Sassafras and may suggest that Sassafras first appeared in Gondwana and later radiated into the Northern Hemisphere. The distribution of extant Sassafras in North America and East Asia may represent a relict of a geographically more widespread taxon in the past.

A New Late Cretaceous (Coniacian-Maastrichtian) Javelinoxylon Wood From Chihuahua, Mexico

IAWA Journal ◽  
2011 ◽  
Vol 32 (4) ◽  
pp. 521-530 ◽  
Author(s):  
Emilio Estrada-Ruiz ◽  
Hugo I. Martínez-Cabrera
Keyword(s):  
Late Cretaceous ◽  
Fossil Record ◽  
Upper Cretaceous ◽  
Fossil Wood ◽  
The State ◽  
Northern Mexico ◽  
Vessel Elements ◽  
Ray Parenchyma ◽  
Perforation Plates ◽  
San Carlos

We describe a new fossil wood from the San Carlos Formation (Coniacian- Maastrichtian) in Chihuahua, northern Mexico. This Malvaceae s.l. wood is diffuse porous, vessels are solitary and in radial multiples, simple perforation plates, small alternate intervessel pits, vessel-ray parenchyma pits that are rounded with reduced borders, septate and nonseptate fibers, homocellular and heterocellular rays, and storied rays and vessel elements. These features support its inclusion within the genus Javelinoxylon, Malvaceae s.l., which occurs in other Upper Cretaceous localities in northern Mexico (Olmos Formation) and Texas (Aguja and Javelina Formations). This San Carlos fossil wood is the earliest occurrence of storied structure in the fossil record and the earliest angiosperm record for the State of Chihuahua, Mexico.

scholarly journals A new Late Cretaceous iguanomorph from North America and the origin of New World Pleurodonta (Squamata, Iguania)

2017 ◽  
Vol 284 (1847) ◽  
pp. 20161902 ◽  
Author(s):  
David G. DeMar ◽  
Jack L. Conrad ◽  
Jason J. Head ◽  
David J. Varricchio ◽  
Gregory P. Wilson
Keyword(s):  
North America ◽  
Late Cretaceous ◽  
Fossil Record ◽  
New World ◽  
Cladistic Analysis ◽  
Arid Environment ◽  
New Taxon ◽  
Low Latitude ◽  
Anatomical Features ◽  
Parietal Foramen

Iguanomorpha (stem + crown Iguania) is a diverse squamate clade with members that predominate many modern American lizard ecosystems. However, the temporal and palaeobiogeographic origins of its constituent crown clades (e.g. Pleurodonta (basilisks, iguanas, and their relatives)) are poorly constrained, mainly due to a meagre Mesozoic-age fossil record. Here, we report on two nearly complete skeletons from the Late Cretaceous (Campanian) of North America that represent a new and relatively large-bodied and possibly herbivorous iguanomorph that inhabited a semi-arid environment. The new taxon exhibits a mosaic of anatomical features traditionally used in diagnosing Iguania and non-iguanian squamates (i.e. Scleroglossa; e.g. parietal foramen at the frontoparietal suture, astragalocalcaneal notch in the tibia, respectively). Our cladistic analysis of Squamata revealed a phylogenetic link between Campanian-age North American and East Asian stem iguanomorphs (i.e. the new taxon + Temujiniidae). These results and our evaluation of the squamate fossil record suggest that crown pleurodontans were restricted to the low-latitude Neotropics prior to their early Palaeogene first appearances in the mid-latitudes of North America.

scholarly journals A new species of troodontid theropod (Dinosauria: Maniraptora) from the Horseshoe Canyon Formation (Maastrichtian) of Alberta, Canada

2017 ◽  
Vol 54 (8) ◽  
pp. 813-826 ◽  
Author(s):  
David C. Evans ◽  
Thomas M. Cullen ◽  
Derek W. Larson ◽  
Adam Rego
Keyword(s):  
New Species ◽  
North America ◽  
Alpha Diversity ◽  
Width Ratio ◽  
New Taxon ◽  
Lateral Region ◽  
Morphometric Analyses ◽  
Dinosaur Park Formation ◽  
Horseshoe Canyon Formation ◽  
A New Species

Troodontid material from the Maastrichtian of North America is extremely rare, beyond isolated teeth from microvertebrate sites. Here we describe troodontid frontals from the early Maastrichtian Horseshoe Canyon Formation (Horsethief Member). The most complete specimen, TMP 1993.105.0001, is notably foreshortened and robust when compared with numerous specimens referred to Troodon from the Dinosaur Park Formation, and exhibits several characteristics that distinguish it from other Late Cretaceous troodontids. Morphometric analyses reinforce shape differences between TMP 1993.105.0001 and other North American troodontids, and show that proportional differences are independent of size. We therefore erect a new taxon, Albertavenator curriei gen. et sp. nov., which is diagnosed by the following autapomorphies: (1) primary supraciliary foramen is truncated anteriorly by the lacrimal contact; (2) superficial (ectocranial) surface of the frontal proportionally shorter than all known troodontids, with a length to width ratio under 1.3; and (3) frontoparietal contact in which an enlarged lappet of the frontal extends medially to extensively overlap the lateral region of the anteromedial process of the parietal. Interestingly, tooth and jaw morphology from the single relatively complete dentary recovered from the Horseshoe Canyon cannot be distinguished from dentaries and teeth from the Dinosaur Park Formation. If the dentary and teeth from the Horsethief Member of the Horseshoe Canyon Formation prove to belong to A. curriei, extensive overlap in tooth morphology between the Dinosaur Park and Horseshoe Canyon formations reinforces the notion that tooth morphotypes do not exhibit strong correspondence to species alpha diversity, and may encompass multiple closely related taxa.

Cretaceous Woods from the Farafra Oasis, Egypt

IAWA Journal ◽  
2006 ◽  
Vol 27 (2) ◽  
pp. 137-143 ◽  
Author(s):  
Marwah M. Kamal El-Din ◽  
E.A Wheeler ◽  
J.A. Bartlett
Keyword(s):  
North America ◽  
Late Cretaceous ◽  
The Other ◽  
Axial Parenchyma ◽  
Perforation Plates

There are fewer than 200 angiosperm wood records for the whole of the Cretaceous; the majority are from North America, Europe, and Asia. This paper describes two petrified woods from the Late Cretaceous Hefhuf Formation, Farafra Oasis, Egypt, a locality near the Campanian equator. Affinities of these two wood types cannot be determined with certainty. One wood has characteristics seen in the Lauraceae, Moraceae, and Anacardiaceae; the other wood has exclusively uniseriate homocellular rays, scalariform perforation plates, rare axial parenchyma, and alternate-opposite intervessel pitting.

scholarly journals The youngest South American rhynchocephalian, a survivor of the K/Pg extinction

2014 ◽  
Vol 281 (1792) ◽  
pp. 20140811 ◽  
Author(s):  
Sebastián Apesteguía ◽  
Raúl O. Gómez ◽  
Guillermo W. Rougier
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
New Zealand ◽  
South America ◽  
Late Cretaceous ◽  
South American ◽  
New Taxon ◽  
Northern Patagonia ◽  
Extinction Event ◽  
New Form

Rhynchocephalian lepidosaurs, though once widespread worldwide, are represented today only by the tuatara ( Sphenodon ) of New Zealand. After their apparent early Cretaceous extinction in Laurasia, they survived in southern continents. In South America, they are represented by different lineages of Late Cretaceous eupropalinal forms until their disappearance by the Cretaceous/Palaeogene (K/Pg) boundary. We describe here the only unambiguous Palaeogene rhynchocephalian from South America; this new taxon is a younger species of the otherwise Late Cretaceous genus Kawasphenodon . Phylogenetic analysis confirms the allocation of the genus to the clade Opisthodontia. The new form from the Palaeogene of Central Patagonia is much smaller than Kawasphenodon expectatus from the Late Cretaceous of Northern Patagonia. The new species shows that at least one group of rhynchocephalians not related to the extant Sphenodon survived in South America beyond the K/Pg extinction event. Furthermore, it adds to other trans-K/Pg ectotherm tetrapod taxa, suggesting that the end-Cretaceous extinction affected Patagonia more benignly than the Laurasian landmasses.

Species composition of the Late Cretaceous eutherian mammal Paranyctoides Fox

2013 ◽  
Vol 50 (7) ◽  
pp. 693-700 ◽  
Author(s):  
Marisol Montellano-Ballesteros ◽  
Richard C. Fox ◽  
Craig S. Scott
Keyword(s):  
North America ◽  
Species Composition ◽  
Central Asia ◽  
Late Cretaceous ◽  
Geographic Range ◽  
Eutherian Mammal ◽  
The Past ◽  
Central Asian ◽  
Dinosaur Park Formation ◽  
Eutherian Evolution

Although the known record of Mesozoic eutherian mammals has been significantly enriched in recent years, early eutherian evolution is still not well understood. Among the more controversial of Mesozoic eutherians is Paranyctoides Fox, which was described in 1979 from the Judithian Dinosaur Park Formation, Alberta, Canada. It is a rare taxon and therefore has been identified in only a few other North American Late Cretaceous local faunas since. Within the past decade, dental and gnathic remains discovered in Central Asia have also been referred to Paranyctoides, thereby expanding the geographic range of the genus substantially and making it the only Late Cretaceous eutherian ostensibly occurring in both continents. As a result of our detailed study of Paranyctoides, however, we find that the Central Asian species lack the diagnostic characters of Paranyctoides and must be referred to other taxa. We conclude that this genus was limited to North America, ranging from Aquilan to Lancian time, and accordingly we recognize as valid only the following species: Paranyctoides sternbergi (Judithian, Alberta), P. maleficus (Aquilan, Alberta), Paranyctoides Wahweap sp. A and sp. B (Judithian, Utah), Paranyctoides Kaiparowits sp. A and sp. B (Judithian, Utah). Another purported species of Paranyctoides, P. megakeros, from the Lancian of Wyoming, is a junior synonym of Alostera saskatchewanensis.

REVISION OF THE NEW WORLD CHRYSOLAMPINAE (HYMENOPTERA: CHALCIDOIDEA)

1986 ◽  
Vol 118 (9) ◽  
pp. 913-940 ◽  
Author(s):  
D. Christopher Darling
Keyword(s):  
New Species ◽  
North America ◽  
Late Cretaceous ◽  
New World ◽  
World Species ◽  
European Species ◽  
Extant Species ◽  
Three New Species ◽  
First Time ◽  
Climatic Information

AbstractThe taxonomy and biology of New World species of Chrysolampinae are reviewed with diagnoses given for the subfamily, genera, and species. A key to the species of Chrysolampus and a summary of geographic distribution and information on host and floral associations are presented. Three new species are described from North America (Chrysolampus improcerus, C. luridus and C. elegans); Chrysolampus lycti Crawford is transferred to Perilampus and synonymized with the European species P. micans Dalman. The genus Chrysomalla is recorded in the New World for the first time based on the new species Chrysomalla hesperis. An explanation of the historical biogeography of the genera is proposed that is consistent with Late Cretaceous and Tertiary geological, botanical, and climatic information. It is suggested that the extant species are descendents of elements of a widely distributed arid biota.

Late Santonian megaspore floras from the Gulf Coastal Plain (Georgia, USA)

2011 ◽  
Vol 85 (1) ◽  
pp. 1-21 ◽  
Author(s):  
Richard Lupia
Keyword(s):  
New Species ◽  
North America ◽  
Late Cretaceous ◽  
Coastal Plain ◽  
Eastern North America ◽  
Gulf Coastal Plain ◽  
Two New Species ◽  
Western Interior Basin ◽  
Heterosporous Ferns

Fossil megaspore floras from the Late Cretaceous of North America have been studied extensively, but primarily from the Western Interior Basin. Two new megaspore floras are described from eastern North America along the Gulf Coastal Plain. Cumulatively, 10 genera and 16 species of megaspores are recognized from Allon, Georgia and along Upatoi Creek, Georgia (both late Santonian in age, ~84 Ma). Megaspores identified have affinities to both heterosporous lycopsids, e.g., Erlansonisporites, Minerisporites, and Paxillitriletes, and to heterosporous ferns, e.g., Ariadnaesporites, and Molaspora. Lycopsid megaspores are more diverse than fern megaspores in the Allon and the Upatoi Creek floras. Two new species—Erlansonisporites confundus n. sp. and Erlansonisporites potens n. sp.—are proposed.

scholarly journals A new species of troodontid theropod (Dinosauria: Maniraptora) from the Horseshoe Canyon Formation (Maastrichtian) of Alberta, Canada

2018 ◽  
Author(s):  
David Evans ◽  
Thomas Cullen ◽  
Derek Larson ◽  
Adam Rego
Keyword(s):  
New Species ◽  
North America ◽  
Alpha Diversity ◽  
Width Ratio ◽  
New Taxon ◽  
Lateral Region ◽  
Morphometric Analyses ◽  
Dinosaur Park Formation ◽  
Horseshoe Canyon Formation ◽  
A New Species

Troodontid material from the Maastrichtian of North America is extremely rare, beyond isolated teeth from microvertebrate sites. Here we describe troodontid frontals from the early Maastrichtian Horseshoe Canyon Formation (Horsethief Member). The most complete specimen, TMP 1993.105.0001, is notably foreshortened and robust when compared with numerous specimens referred to Troodon from the Dinosaur Park Formation, and exhibits several characteristics that distinguish it from other Late Cretaceous troodontids. Morphometric analyses reinforce shape differences between TMP 1993.105.0001 and other North American troodontids, and show that proportional differences are independent of size. We therefore erect a new taxon, Albertavenator curriei gen. et sp. nov., which is diagnosed by the following autapomorphies: (1) primary supraciliary foramen is truncated anteriorly by the lacrimal contact; (2) superficial (ectocranial) surface of the frontal proportionally shorter than all known troodontids, with a length to width ratio under 1.3; and (3) frontoparietal contact in which an enlarged lappet of the frontal extends medially to extensively overlap the lateral region of the anteromedial process of the parietal. Interestingly, tooth and jaw morphology from the single relatively complete dentary recovered from the Horseshoe Canyon cannot be distinguished from dentaries and teeth from the Dinosaur Park Formation. If the dentary and teeth from the Horsethief Member of the Horseshoe Canyon Formation prove to belong to A. curriei, extensive overlap in tooth morphology between the Dinosaur Park and Horseshoe Canyon formations reinforces the notion that tooth morphotypes do not exhibit strong correspondence to species alpha diversity, and may encompass multiple closely related taxa.

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