stratigraphic range
Recently Published Documents


TOTAL DOCUMENTS

171
(FIVE YEARS 26)

H-INDEX

19
(FIVE YEARS 1)

2021 ◽  
Vol 69 ◽  
pp. 215-232
Author(s):  
Kai Ingemann Schnetler ◽  
Mogens Stentoft Nielsen

The predominantly Cretaceous gastropod genus Vanikoropsis Meek, 1876 is represented in the Paleocene of Denmark and West Greenland by four species, of which three are established herein as new, viz. Vanikoropsis mortenseni n. sp., Vanikoropsis (s.l.) jakobseni n. sp. and Vanikoropsis (s.l.) bashforthi n. sp. The Danish species was found in a boulder of Kerteminde Marl (Selandian, middle Paleocene) from Gundstrup, while the species from West Greenland were found in the localities Sonja Lens and Qaarsutjægerdal on the Nuussuaq peninsula (late Danian, early Paleocene). The Danish species extends the stratigraphic range of the genus into the middle Paleocene and supports the affinities of the Kerteminde Marl fauna to the Paleocene fauna of West Greenland.


2021 ◽  
Vol 73 (3) ◽  
pp. A301220
Author(s):  
Torrey Nyborg ◽  
Alessandro Garassino ◽  
Brant Nyborg ◽  
Francisco J. Vega

A new cyclodorippid crab, Berglundus bretoni n. gen., n. sp. (Cyclodorippidae Ortmann, 1892) from the Astoria Formation (early to middle Miocene) of Washington State is herein described. It represents the fourth genus of cyclodorippids in North America, keeping the stratigraphic range and the palaeogeographic distribution of the Cyclodorippidae unchanged.


2021 ◽  
pp. 1-22
Author(s):  
Heda Agić ◽  
Anette E.S. Högström ◽  
Sören Jensen ◽  
Jan Ove R. Ebbestad ◽  
Patricia Vickers-Rich ◽  
...  

Abstract New occurrences of flask-shaped and envelope-bearing microfossils, including the predominantly Cambrian taxon Granomarginata, are reported from new localities, as well as from earlier in time (Ediacaran) than previously known. The stratigraphic range of Granomarginata extends into the Cambrian System, where it had a cosmopolitan distribution. This newly reported Ediacaran record includes areas from Norway (Baltica), Newfoundland (Avalonia) and Namibia (adjacent to the Kalahari Craton), and puts the oldest global occurrence of Granomarginata in the Indreelva Member (< 563 Ma) of the Stáhpogieddi Formation on the Digermulen Peninsula, Arctic Norway. Although Granomarginata is rare within the assemblage, these new occurrences together with previously reported occurrences from India and Poland, suggest a potentially widespread palaeogeographic distribution of Granomarginata through the middle–late Ediacaran interval. A new flask-shaped microfossil Lagoenaforma collaris gen. et sp. nov. is also reported in horizons containing Granomarginata from the Stáhpogieddi Formation in Norway and the Dabis Formation in Namibia, and flask-shaped fossils are also found in the Gibbett Hill Formation in Newfoundland. The Granomarginata–Lagoenaforma association, in addition to a low-diversity organic-walled microfossil assemblage, occurs in the strata postdating the Shuram carbon isotope excursion, and may eventually be of use in terminal Ediacaran biostratigraphy. These older occurrences of Granomarginata add to a growing record of body fossil taxa spanning the Ediacaran–Cambrian boundary.


2021 ◽  
Author(s):  
Kevin Stevens

Belemnites are common fossil coleoid cephalopods of the Mesozoic. They began to diversify in the Triassic-Early Jurassic and maintained this diversity until the early Early Cretaceous. During the mid-Cretaceous, they declined in diversity and distribution, being restricted to only the Boreal and Austral Realm since the Turonian. Here, I present the first cladistic analysis of belemnite phylogeny, spanning taxa representative of the whole diversity and stratigraphic range of the group. This analysis shows that the usually applied subdivision of all belemnites into "Belemnitina" and "Belemnopseina" is not supported. A newly identified clade, the Pseudoalveolata, is suggested here. Pseudoalveolate belemnites represent the last remaining belemnites after the Aptian. Oceanic anoxia and warming are likely the main cause of the mid- Cretaceous belemnite decline, resulting in the Aptian-Albian dominance of the warm-adapted pseudoalveolate genus Neohibolites. The rise of teleost fish diversity during the mid- Cretaceous is discussed and its relevance for belemnite evolution. Some teleosts (e.g., Enchodus) might have taken over the mesopredator niches left by belemnites during the mid- Cretaceous, being better adapted to warming seas. Belemnites were not able to recover their earlier widespread distribution and diversity and the last remaining, disjunctly distributed families, the northern Belemnitellidae and southern Dimitobelidae, became extinct at the K/Pg-boundary.


2021 ◽  
Vol 40 (2) ◽  
pp. 145-161
Author(s):  
Bridget S. Wade ◽  
Mohammed H. Aljahdali ◽  
Yahya A. Mufrreh ◽  
Abdullah M. Memesh ◽  
Salih A. AlSoubhi ◽  
...  

Abstract. The Rashrashiyah Formation of the Sirhan Basin in northern Saudi Arabia contains diverse assemblages of planktonic foraminifera. We examined the biostratigraphy, stratigraphic range and preservation of upper Eocene planktonic foraminifera. Assemblages are well-preserved and diverse, with 40 species and 11 genera. All samples are assigned to the Priabonian Globigerinatheka semiinvoluta Highest Occurrence Zone (E14), consistent with calcareous nannofossil biostratigraphy indicating Zone CNE17. Well-preserved planktonic foraminifera assemblages from the lower part of the upper Eocene are rare worldwide. Our study provides new insights into the stratigraphic ranges of many species. We find older (Zone E14) stratigraphic occurrences of several species of Globoturborotalita previously thought to have evolved in the latest Eocene (Zone E15, E16) or Oligocene; these include G. barbula, G. cancellata, G. gnaucki, G. pseudopraebulloides, and G. paracancellata. Older stratigraphic occurrences for Dentoglobigerina taci and Subbotina projecta are also found, and Globigerinatheka kugleri occurs at a younger stratigraphic level than previously proposed. Our revisions to stratigraphic ranges indicate that the late Eocene had a higher tropical–subtropical diversity of planktonic foraminifera than hitherto reported.


2021 ◽  
Vol 4 (5) ◽  
Author(s):  
WIESŁAW KRZEMIŃSKI ◽  
KATARZYNA KOPEĆ ◽  
AGNIESZKA SOSZYŃSKA-MAJ ◽  
KORNELIA SKIBIŃSKA

The family Limoniidae is the most speciose family of the infraorder Tipulomorpha, as well as one of the largest families of nematoceran Diptera. The oldest known representative of Limoniidae is Architipula youngi Krzemiński, 1992 described from the Upper Triassic of North America (ca. 208 Ma) belonging to the subfamily Architipulinae (Krzemiński, 1992). The subfamily Limoniinae (Limoniidae) stratigraphic range extends from the Lower Cretaceous Lebanese amber (Kania et al., 2014) to the present day, and is divided into two tribes, namely Antochini and Limoniini Savchenko (1985). Antochini currently comprise of the following contemporary genera: Antocha Alexander, 1924 (represented by 160 species); Elliptera Schiner, 1863 (represented by 12 species); Orimarga Osten-Sacken, 1869 (represented by 150 species) and Thaumastoptera Mik, 1866 (represented by 11 species). Representatives of this tribe currently occur on all continents except Antarctica, but individual genera are not distributed uniformly throughout the world (Oosterbroek, 2021). Although the family Limoniidae has been known since the Upper Triassic (Krzemińska & Krzemiński, 2003), the oldest representative of the tribe Antochini is only known from the beginning of the Upper Cretaceous from the Burmese amber from Kachin (Podenas & Poinar, 2009) dated to ca. 99 Ma (Shi et al., 2012).


2021 ◽  
pp. 1-55
Author(s):  
Javier Echevarría ◽  
Susana E. Damborenea ◽  
Miguel O. Manceñido

Abstract Bivalves of the Order Trigoniida were abundant and diverse in the Andean Early Jurassic shallow-marine paleoenvironments. Based on extensive collections with detailed stratigraphic information from 40 localities in central-western Argentina, we describe 20 species (4 new) belonging to 11 genera (3 new) and 5 families (Groeberellidae, Trigoniidae, Prosogyrotrigoniidae, Frenguelliellidae, and Myophorellidae). The abundant material allows the description of ontogenetic development and intraspecific variability, highlighting the likely phylogenetic significance of previously underestimated features. Within Frenguelliellidae, we show that the stratigraphic range of Frenguelliella Leanza in the region is restricted to the Sinemurian–Pliensbachian. We propose Poultoniella new genus for some late Pliensbachian–Toarcian species. Jaworskiella Leanza is limited to its type species, whereas for certain convergent forms we propose Moerickella new genus (most likely the oldest Myophorellidae). Pseudovaugonia new genus likely descended from Moerickella n. gen., rather than from the highly diverse Promyophorella Kobayashi and Tamura, and is unrelated to Vaugonia Crickmay. Frenguelliella chubutensis (Feruglio) and Promyophorella basoaltorum new species are the most frequently occurring species. Some species were probably endemic (e.g., Promyophorella? sanjuanina new species), although a few (such as Frenguelliella eopacifica new species and Poultoniella jaworskii new genus new species) had a wide paleolatitudinal range and occur throughout the Pacific coasts and terranes of the Americas, revealing a significant faunal interchange among marine basins during Hettangian–Pliensbachian times. The well-documented Argentinian Early Jurassic record shows a rapid recovery and radiation of the Trigoniida after the Triassic/Jurassic extinction. Many of the new taxa that evolved in America eventually dispersed worldwide by Toarcian and Middle Jurassic times. UUID: http://zoobank.org/82c0d95e-f147-4736-a417-ebc252911181.


2021 ◽  
pp. 1-16
Author(s):  
Juan Carlos Gutiérrez-Marco ◽  
Ladislav Marek ◽  
John M. Malinky

Abstract The record of Middle Ordovician (Oretanian, ca. Darriwilian 2) hyolithids from the Ossa Morena Zone of the Iberian Massif in southwestern Spain is increased with the recognition of Robardetlites sevillanus n. gen. n. sp., Andalucilites parvulus n. gen. n. sp., Pauxillites desolatus n. sp., Leolites malinkyi Marek and Gutiérrez-Marco n. sp., and Cavernolites sp. in that region. Andalucilites n. gen. and Robardetlites n. gen. are endemic whereas the other genera are known from coeval strata in the Barrandian region in central Europe, France, and Morocco, giving this assemblage a decidedly “Mediterranean province” character. The discovery of Pauxillites, Leolites, and Cavernolites in Iberia extends their geographic ranges to that region, and Leolites from this area extends its stratigraphic range downward, making its occurrence in Iberia the oldest known for that genus. UUID: http://zoobank.org/f5b29223-6dac-4c7e-8851-551e634da667


2021 ◽  
Vol 140 (1) ◽  
Author(s):  
Javad Sharifi ◽  
Amane Tajika ◽  
Alireza Mohammadabadi ◽  
Mohammad Hossein Tabari Abkuh

AbstractThe Aitamir Formation, situated in the Koppeh Dagh Basin in the northeast of Iran, is known for its well-exposed Albian-to-Cenomanian succession. Although geologists previously documented a number of macro- and microfossils, no nautilids had been discovered until now to our knowledge. Here, we present lower Albian and middle Cenomanian nautilids from the Koppeh Dagh Basin for the first time. This discovery is also the first record of Cretaceous nautilids from Iran. We identified the specimens as Eutrephoceras clementianum (d’Orbigny 1840), E. sublaevigatum (d’Orbigny 1850), E. bouchardianum (d’Orbigny 1840) and Eutrephoceras sp. These specimens occur in horizons situated between several ammonite-bearing levels, which allowed us to more precisely constrain age estimates for the recovered nautilid specimens. E. clementianum could not be dated precisely but likely comes from between late Aptian ammonite index Hypacanthoplites uhligi and middle Albian Hoplites (Hoplites) baylei. E. sublaevigatum occurs just above the late Albian ammonites Mariella bergeri and Semenoviceras michalskii and below the Mantelliceras mantelli Zone. At the upper part of the section, E. bouchardianum and Eutrephoceras sp. were collected from lower Albian beds, which correspond to the Mantelliceras mantelli and Mantelliceras dixonii zones. These new findings contribute to our knowledge of the geographical distribution and stratigraphic range of Albian–Cenomanian nautilid species.


2021 ◽  
Vol 21 (12) ◽  
pp. 235-263
Author(s):  
Cyril Baudouin ◽  
Gérard Delanoy ◽  
Jens Lehmann ◽  
Camille Frau ◽  
Roland Gonnet ◽  
...  
Keyword(s):  

The occurrence of the nautiloid genus Anglonautilus Spath in France was limited to the report of Anglonautilus dorsoplicatus (Wiedmann) from the Albian of Escragnolles (Alpes-Maritimes) and Anglonautilus sp. from the Aptian of Les Ferres (Alpes-Maritimes). Here we document the presence of the successive species Anglonautilus praeundulatus Lehmann et al., Anglonautilus undulatus (Sowerby) and Anglonautilus dorsoplicatus (Wiedmann) from the Cretaceous of France. The stratigraphic range of Anglonautilus Spath, hitherto unknown before Aptian times is extended downward to the Hauterivian. The Hauterivian species Nautilus begudensis Kilian & Reboul, sometimes assigned to the genus Anglonautilus Spath, is revised and re-assigned to the genus Cymatoceras Hyatt.


Sign in / Sign up

Export Citation Format

Share Document