A Primitive Therian Mammal from the Upper Cretaceous of Alberta

1972 ◽  
Vol 9 (11) ◽  
pp. 1479-1494 ◽  
Author(s):  
Richard C. Fox

The discovery of tribosphenic molars of primitive construction in the Upper Milk River Formation (early Campanian), Alberta, documents the occurrence of a relict middle Late Cretaceous mammalian species that shows closest dental resemblance to Lower Cretaceous therians of metatherian–eutherian grade now classified as Theria, incertae sedis. The molar crowns of This new species have a wide stylar shelf, small, low protocone, distal trigonid crest, and lack conules and a shelf-like preparaconule crista mesial to the paracone; these and other coronal features indicate a more primitive level of molar evolution than known for Cretaceous Metatheria or Eutheria. Although too late in time to be ancestral to Cretaceous higher Theria, the new Milk River species may clarify aspects of their origin.

1997 ◽  
Vol 71 (2) ◽  
pp. 287-298 ◽  
Author(s):  
Richard L. Squires ◽  
Louella R. Saul

The Cretaceous and early Cenozoic species of the shallow-marine, warm-water bivalve Plicatula from California (United States) and Baja California (Mexico) are reviewed, and three new species are named. All of these species are representatives of Plicatula and not of the closely related taxon Harpax, which is associated with high-latitude and cool-water regions. The earliestknown Cretaceous species of Plicatula from the study area is P. variata Gabb, 1864, from Lower Cretaceous (Hauterivian Stage) strata in northern California, and our studies show it to be conspecific with Plicatula onoensis Anderson, 1958.Plicatula allisoni new species is from Lower Cretaceous (Albian Stage) strata in Baja California, Mexico. Plicatula modjeskaensis new species is from Upper Cretaceous (Turonian Stage) strata in the Santa Ana Mountains, southern California. A possible new species from the same strata is also mentioned. A poorly preserved specimen of Plicatula? sp. is known from Upper Cretaceous (upper Campanian to lower Maastrichtian) strata in northern California.The only Paleocene species of Plicatula from the study area is P. ostreiformis Stanton, 1896, from lower Paleocene strata of Lake County, northern California, and our studies show it to be conspecific with Ostrea buwaldana Dickerson, 1914. The only previously described Eocene species of Plicatula from the study area is P. juncalensis Squires, 1987, from lower middle Eocene (“Capay Stage”) strata of Los Angeles County, southern California. Plicatula surensis new species is from middle lower Eocene (“Capay Stage”) strata in Baja California Sur, Mexico. In addition, there is a Plicatula? sp. from Eocene strata of Baja California Sur, Mexico.Although Plicatula is of uncommon occurrence north of Baja California, its thermophilic trait makes it useful in recognizing periods of warm climate.


Zootaxa ◽  
2019 ◽  
Vol 4567 (3) ◽  
pp. 546 ◽  
Author(s):  
DALE E. GREENWALT ◽  
VLADIMIR A. BLAGODEROV

The dipteran family Bolitophilidae, with the single extant genus Bolitophila, is a small family of mycophagous flies. In marked contrast to related families such as Sciaridae and Mycetophilidae, the family has a poor fossil record with no definite species assigned to the genus. In addition, the position of the extinct Cretaceous subfamily Mangasinae Kovalev, 1986 (described in Bolitophillidae) has been controversial and it has been suggested that species in this clade may belong to other sciaroid families. This situation is made worse by misplacement of the type specimen. We herein describe two new species of Bolitophila, Bolitophila warreni sp. nov. from the 46-million-year-old Kishenehn Formation in Montana, USA and Bolitophila rohdendorfi sp. nov. from Baltic amber. Bolitophila pulveris Lewis, 1969 is reassigned to Sciaroidea incertae sedis. The subfamily Mangasinae is reviewed and its position within the Bolitophilidae confirmed. Two new species of Mangas, M. kovalevi sp. nov. and M. brevisubcosta sp. nov., both from the Lower Cretaceous of Khasurty in Western Transbaikalia, are described. 


1994 ◽  
Vol 68 (6) ◽  
pp. 1321-1335 ◽  
Author(s):  
T. Markham Puckett

This paper describes new species of Ostracoda from Late Cretaceous (late Santonian) oyster reefs of the Eutaw Formation of eastern Alabama. The reefs are composed almost exclusively of Ostrea cretacea Morton, with rarer occurrences of the oysters Exogyra upatoiensis Stephenson and Lopha ucheensis (Stephenson) and the bivalve Anomia preolmstedi Stephenson. Total thickness of the reefs is about 30 m, and the reefs are a major topographic feature across most of Macon and Russell Counties, Alabama, a distance of about 60 km. The reefs are interpreted to have been backbarrier sediments deposited under brackish conditions.Eight species of ostracodes are identified, including five new species described herein. The fauna is typically well preserved, and includes males, females, and juveniles. New species include Haplocytheridea? eutawensis, Antibythocypris dimorphicus, A. nephotrema, Brachycythere asymmetrica, and Eocytheropteron mutafoveata. Also discussed and illustrated are Cytherella tuberculifera Alexander, Haplocytheridea renfroensis renfroensis Crane, and Fissocarinocythere gapensis (Alexander).


1997 ◽  
Vol 71 (4) ◽  
pp. 615-620 ◽  
Author(s):  
Francisco J. Vega ◽  
Rodney M. Feldmann ◽  
Adriana C. Ocampo ◽  
Kevin O. Pope

A new species of carcineretid crab, Carcineretesplanetarius, is described from the Upper Cretaceous (lower Maastrichtian) Barton Creek Dolomite at Albion Island, Belize. The age is based on the stratigraphic range of associated nerineid gastropods and correlation with nannoplankton, benthic foraminifera, and the other known congeneric species of crab found in Jamaica. Confirmation of this age aids in constraining the timing of ejecta deposits of the Chicxulub impact found at the top of Barton Creek Dolomite exposed on Albion Island. Paleoenvironmental and paleoecological analyses suggest that these crabs were swimmers in lagoonal settings, capable of burrowing a few centimeters into the mud for protection.


Zootaxa ◽  
2019 ◽  
Vol 4603 (2) ◽  
pp. 341 ◽  
Author(s):  
DMITRY S. KOPYLOV

Four new genera and five new species of anaxyelids are described from the Cretaceous of Asia: Mangus magnus gen. et sp. nov. from the Aptian of Mongolia (Bon-Tsagan), Urosyntexis undosa sp. nov., Parasyntexis khasurtensis gen. et sp. nov., both from the Early Cretaceous of Transbaikalia (Khasurty), Dolichosyntexis transbaikalicus gen. et sp. nov. from the Hauterivian–Barremian of Transbaikalia (Baissa), and Curiosyntexis magadanicus gen. et sp. nov. from the mid-Upper Cretaceous of NE Siberia (Obeshchayushchiy). Early Cretaceous is the time of the highest diversity of Anaxyelidae. In this epoch these sawflies are represented with all four subfamilies comprising the group. In Late Cretaceous anaxyelid diversity and abundance rapidly decrease and they are represented with the only subfamily Syntexinae. The anaxyelid collection of Palaeontological Institute (Moscow), the most representative collection of fossil anaxyelids in the world, has been completely revised, identified and described. The list of identifications is provided.


1980 ◽  
Vol 17 (11) ◽  
pp. 1489-1498 ◽  
Author(s):  
Richard C. Fox

A new therian mammal of primitive tribosphenic grade is described from the Upper Milk River Formation (Upper Cretaceous) of Alberta, Canada, and its relationships to other primitive tribosphenic therians are discussed. The new therian and its presumed nearest relatives form the basis of a new family within the Order Aegialodontia. A revised classification of the Infraclass Tribotheria is presented.


1971 ◽  
Vol 8 (8) ◽  
pp. 916-938 ◽  
Author(s):  
Richard C. Fox

Mammalian teeth collected from the early Campanian Upper Milk River Formation, southernmost Alberta, document a hitherto unknown evolutionary radiation of Late Cretaceous ptilodontoid and taeniolabidoid multituberculates. New species of the ectypodontids Mesodma and Cimexomys, the ptilodontid Cimolodon, and the cimolomyid Meniscoessus are defined, and teeth possibly pertaining to a second species of Mesodma and two species of Cimolomys are described. A new genus and species with uncertain relationships to known multituberculate families, is tentatively classified in the Taeniolabidoidea. Among North American Late Cretaceous multituberculates, at least Mesodma, Cimexomys, Cimolodon, Cimolomys, and Meniscoessus are seen to be evolutionarily conservative during early Campanian to late Maestrichtian times. The effects of sampling error on relative taxonomic diversity at horizons in the North American Upper Cretaceous are discussed.


2021 ◽  
pp. 83-94
Author(s):  
FELIX SCHLAGINTWEIT

An assemblage of agglutinated conical foraminifera including Lepinoconus chiocchinii Cruz-Abad et al., Calveziconus lecalvezae Caus & Cornella, Paleodictyoconus sp., and Paracoskinolina klokovaensis n. sp. are described from the upper lower-middle Campanian of Klokova Mountain of the Gavrovo-Tripolitza Zone, SW continental Greece. With the presence of one rafter in the marginal zone, the new species P. klokovaensis compares to the Lower Cretaceous species Paracoskinolina arcuata (Arnaud-Vanneau) that is distinguished by its cylindroconical test morphology and much larger size. The assemblage occurs in inner platform carbonates associated with other foraminifers such as dicyclinids, and Accordiella conica Farinacci. Representatives of the genus Paracoskinolina were so far only reliably reported from the Upper Berriasian–Albian interval. This new record suggests that the genus either survived the larger benthic foraminifera extinction event associated with the Cenomanian – Turonian boundary anoxic event, or may be an example of an Elvis taxon or homoplasy.


1992 ◽  
Vol 32 (1) ◽  
pp. 231 ◽  
Author(s):  
A.M.G. Moore ◽  
J.B. Willcox ◽  
N.F. Exon ◽  
G.W. O'Brien

The continental margin of western Tasmania is underlain by the southern Otway Basin and the Sorell Basin. The latter lies mainly under the continental slope, but it includes four sub-basins (the King Island, Sandy Cape, Strahan and Port Davey sub-basins) underlying the continental shelf. In general, these depocentres are interpreted to have formed at the 'relieving bends' of a major left-lateral strike-slip fault system, associated with 'southern margin' extension and breakup (seafloor spreading). The sedimentary fill could have commenced in the Jurassic; however, the southernmost sub-basins (Strahan and Port Davey) may be Late Cretaceous and Paleocene, respectively.Maximum sediment thickness is about 4300 m in the southern Otway Basin, 3600 m in the King Island Sub-basin, 5100 m in the Sandy Cape Basin, 6500 m in the Strahan Sub-basin, and 3000 m in the Port Davey Sub-basin. Megasequences in the shelf basins are similar to those in the Otway Basin, and are generally separated by unconformities. There are Lower Cretaceous non-marine conglomerates, sandstones and mudstones, which probably include the undated red beds recovered in two wells, and Upper Cretaceous shallow marine to non-marine conglomerates, sandstones and mudstones. The Cainozoic sequence often commences with a basal conglomerate, and includes Paleocene to Lower Eocene shallow marine sandstones, mudstones and marl, Eocene shallow marine limestones, marls and sandstones, and Oligocene and younger shallow marine marls and limestones.The presence of active source rocks has been demonstrated by the occurrence of free oil near TD in the Cape Sorell-1 well (Strahan Sub-basin), and thermogenic gas from surficial sediments recovered from the upper continental slope and the Sandy Cape Sub-basin. Geohistory maturation modelling of wells and source rock 'kitchens' has shown that the best locations for liquid hydrocarbon entrapment in the southern Otway Basin are in structural positions marginward of the Prawn-1 well location. In such positions, basal Lower Cretaceous source rocks could charge overlying Pretty Hill Sandstone reservoirs. In the King Island Sub-Basin, the sediments encountered by the Clam-1 well are thermally immature, though hydrocarbons generated from within mature Lower Cretaceous rocks in adjacent depocentres could charge traps, providing that suitable migration pathways are present. Whilst no wells have been drilled in the Sandy Cape Sub-basin, basal Cretaceous potential source rocks are considered to have entered the oil window in the early Late Cretaceous, and are now capable of generating gas/condensate. Upper Cretaceous rocks appear to have entered the oil window in the Paleocene. In the Strahan Sub-Basin, mature Cretaceous sediments in the depocentres are available to traps, though considerable migration distances would be required.It is concluded that the west Tasmania margin, which has five strike-slip related depocentres and the potential to have generated and entrapped hydrocarbons, is worthy of further consideration by the exploration industry. The more prospective areas are the southern Otway Basin, and the Sandy Cape and Strahan sub-basins of the Sorell Basin.


2012 ◽  
Vol 86 (1) ◽  
pp. 126-128
Author(s):  
Rodney M. Feldmann ◽  
Jeffrey D. Stilwell

Recognition of a fossil previously identified as a “large Cretaceous beetle” as a glypheid lobster permits the definition of a new species, Glyphea wiffenae. The specimen was collected from the richly fossiliferous, Upper Cretaceous Maungataniwa Sandstone in eastern North Island, New Zealand. Several other fossil decapods with high southern latitude affinities have been described previously from the unit, supporting the placement of the Zealandia region within the Weddellian Biotic Province. This is only the fourth glypheid known from New Zealand and the first Cretaceous occurrence of the genus in the country.


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