The operculum of Otostoma Retzii (Nilsson, 1827) (Gastropoda, Neritidae; Late Cretaceous) and its phylogenetic significance

2008 ◽  
Vol 82 (1) ◽  
pp. 201-205
Author(s):  
John W. M. Jagt ◽  
Steffen Kiel

The Neritimorph gastropod genus Otostoma d'Archiac, 1859 (p. 871), with its hemispherical shell and typical axial ribs and lamellae, is a characteristic fossil in (sub)tropical, nearshore deposits of the late Early and Late Cretaceous ages (Saul and Squires, 1997; Kiel, 2002; Kiel et al., 2002; Bandel and Kiel, 2003). The genus survived Cretaceous/Paleogene boundary perturbations and appears to have become extinct during the Middle Eocene (Glibert, 1973; Saul and Squires, 1997). Its placement in the Neritimorpha Golikov and Starobogatov, 1975 is clear from its typical hemispherical shell and D-shaped inner lip with a row of denticles. Long considered linked to Recent Nerita Linnaeus, 1758 (see Wenz, 1938-1944; Kase, 1984; Squires and Saul, 1993; Bandel and Kiel, 2003), assignment of Otostoma to the Neritoidea Rafinesque, 1815 has recently been corroborated by documentation of dissolved internal walls in Otostoma divaricatum (d'Orbigny, 1842) from the Campanian (Upper Cretaceous) of northeast Spain (Bandel and Kiel, 2003). However, axial (collabral) ornament as seen in Otostoma is unknown in modern neritids, which usually are either smooth or spirally sculptured. Here we describe the operculum of Otostoma retzii (Nilsson, 1827) for the first time; it closely resembles that of Nerita and many species of Neritina Lamarck, 1816, yet differs significantly from those of other neritimorph clades, including Neritopsidae Gray, 1847 and Neritiliidae Schepman, 1908.

2012 ◽  
Vol 62 (1) ◽  
pp. 63-89 ◽  
Author(s):  
Emad Nagm ◽  
Markus Wilmsen

ABSTRACT Nagm, E. and Wilmsen, M. 2012. Late Cenomanian-Turonian (Cretaceous) ammonites from Wadi Qena, central Eastern Desert, Egypt: taxonomy, biostratigraphy and palaeobiogeographic implications. Acta Geologica Polonica, 62 (1), 63-89. Warszawa. In Egypt, marine Upper Cenomanian-Turonian strata are well exposed in the Eastern Desert. The southernmost outcrops are located in the central part of Wadi Qena, where the lower Upper Cretaceous is represented by the fossiliferous Galala and Umm Omeiyid formations. From these strata, numerous ammonites have been collected bed-by-bed and 13 taxa have been identified, which are systematically described herein. Four of them (Euomphalocerascostatum, Vascoceras globosum globosum, Thomasites gongilensis and Pseudotissotia nigeriensis) are recorded from Egypt for the first time. The ammonite ranges are used for a biostratigraphic zonation of the lower Upper Cretaceous succession in the northern and central part of Wadi Qena: the Upper Cenomanian-Lower Turonian has been subdivided into five biozones (including a new upper Lower Turonian biozone based on the occurrence of Pseudotissotia nigeriensis), and one biozone has been recognized in the Upper Turonian. Palaeobiogeographically, the ammonite assemblage has a Tethyan character. During the Early Turonian, influences of the Vascoceratid Province were predominant with strong affinities to typical Nigerian faunas. This shows the significance of faunal exchange between Egypt and Central and West Africa via the Trans-Saharan Seaway. Compared to contemporaneous ammonoid faunas from the northern part of the Eastern Desert, Boreal influences are much less obvious in Wadi Qena. Thus, the present study greatly enhances the knowledge of the Late Cretaceous palaeobiogeography and biostratigraphy of Egypt and adjacent areas.


2020 ◽  
pp. 1-10
Author(s):  
Jonathas S. Bittencourt ◽  
Pedro L. C. R. Vieira ◽  
Raphael M. Horta ◽  
André G. Vasconcelos ◽  
Natália C. A. Brandão ◽  
...  

We report new data on the geology and the fossil record of the Sanfranciscana Basin in sites to the north of the traditionally explored localities within Minas Gerais. The strata in the new explored area are formed by distinct lithologies, encompassing pelitic rocks with caliche levels and metric bodies of cross-bedded sandstone towards the top, similar to the fluviolacustrine beds of the Areado Group in the southern portions of the basin. Also similar to other regions of the São Francisco Craton, the deposits of the Sanfranciscana Basin studied herein lie discordantly to the rocks of the Bambuí Basin. We preliminarily report neopterygian fish scales, little informative archosaurian bones and an association of the ostracods Ilyocypris- Fossocytheridea. This ostracod association is registered for the first time in the Cretaceous of the Sanfranciscana Basin. The ostracods have been collected from the lacustrine, vertebrate-bearing rocks cropping out in Lagoa dos Patos and Coração de Jesus. The cytherideid Fossocytheridea assigns a minimal Aptian age to its bearing rocks. Its association with Ilyocypris was also reported in Upper Cretaceous oligohaline paleoenvironments in Brazil and Argentina, indicating similar depositional conditions to the strata reported in this paper. The putative affinities of the specimens of the Sanfranciscana Basin with F. ventrotuberculata, and their association with Ilyocypris, raise the hypothesis of a younger age for some levels of that basin in northern Minas Gerais, perhaps ranging into the Late Cretaceous. Keywords: Ostracoda, Archosauria, Areado Group, Cretaceous, Gondwana


2010 ◽  
Vol 84 (5) ◽  
pp. 895-917 ◽  
Author(s):  
Richard L. Squires

The Late Cretaceous to late Paleocene record of glycymeridid bivalves in the region extending from the Alaska Peninsula, southward to Baja California, Mexico is studied in detail for the first time. Glycymeris pacifica (Anderson, 1902), of late Cenomanian to late Turonian age, is the earliest known glycymeridid in the study area. Very locally, it is found with the middle to late Turonian Glycymeris yoloensis n. sp. The latter apparently represents some intermediate state between genus Glycymeris da Costa, 1778 and genus Glycymerita Finlay and Marwick, 1937. In the study area, Glycymerita is represented by Glycymerita veatchii (Gabb, 1864), middle to late Turonian to late Campanian; Glycymerita banosensis (Anderson, 1958) new combination, late Campanian to latest Maastrichtian; Glycymerita aleuta n. sp., known only from Alaska and of early Maastrichtian age; and Glycymerita major (Stanton, 1896) new combination, Selandian to Thanetian. All the studied species lived in warm-temperate, shallow-marine waters and were shallow burrowers in fine-grained siliciclastic sediments. Variability in morphology is common in sizeable populations of the various species, especially Glycymerita veatchii, which increased nearly fivefold in size during its 19.5 million-year-long range and culminated in shells up to 84 mm in length.


2006 ◽  
Vol 177 (5) ◽  
pp. 249-266 ◽  
Author(s):  
Grigor Heba ◽  
Gilbert Prichonnet

Abstract Two sections, respectively in the Kruje-Dajt and Makareshi massifs of the Kruja Zone carbonate platform (located in the Apulian passive margin of Albania), and representing a period which extends from the Late Cretaceous to the Eocene, have been studied from several points of view : biostratigraphy, lithology and sequence stratigraphy. The proposed biozonation for the Late Cretaceous which has been established with benthic foraminifera (CsB4, CsB5, CsB6 and CsB7) improves substantially the stratigraphy for this period in this region. Eleven different facies (F1 to F11) characterise the Upper Cretaceous-Paleocene-Eocene carbonate sediments, and are distinguished for the first time. Fourteen sequences in the Kruje-Dajt massif and seven sequences in the Makareshi massif are recognized, using sedimentological criteria and clearly distinguished according to an established model for calcareous facies of this platform. Intense early dolomitization (sebkha type) is generally superimposed to the facies. The two sections represent a mostly homogeneous environment, evolving from the infra to supratidal environments. However, small variations of subenvironments are observed and linked to local and temporary variations of the platform. They are attributed to frequent eustatic fluctuations, and in two cases at least to instabilities of the platform which had cause emergencies and temporal discontinuities at the end of Cretaceous and early Eocene times (ca 20 and 5 m.y.).


Author(s):  
Nathalie BARDET ◽  
Delphine DESMARES ◽  
Raquel SÁNCHEZ-PELLICER ◽  
Silvia GARDIN

Briefly mentioned in 1915 by the palaeontologist Répelin, the mosasaurid Liodon asiaticum Répelin, 1915 was found by a missionary to Africa, Father Ruffier, in Late Cretaceous strata near Jerusalem (without further details on the exact provenance). This material was never described in detail, figured, or revised and was recently rediscovered in the collections of the Muséum d’histoire naturelle of Marseille (Provence, southern France). Here we describe and figure for the first time this material, which now includes more specimens than the original lot mentioned by Répelin, and we propose new systematic assignments for the identified specimens. First of all we demonstrate that the five original vertebrae briefly described by Répelin represent a composite assemblage and are not diagnostic at the specific level. Thus Liodon asiaticum should be considered a nomem dubium. The most complete and diagnostic specimen belongs to a Mosasaurini (Mosasaurinae) incertae sedis, close to Mosasaurus Conybeare, 1822 and Plotosaurus Camp, 1951, as shown by the unique configuration of its frontal-parietal-postorbitofrontal complex. The two other specimens are identified as indeterminate Mosasaurinae. The study of several groups of microfossils (calcareous nannofossils, planktonic foraminifera and palynomorphs) found in the white chalk preserved with most of the bones constrains the age of these mosasaurid remains to the lower part of the middle Campanian (C. plummerae (Gandolfi, 1955) / G. rosetta (Carsey, 1926) and CC18 / UC14-15a Zones). This corresponds to the local Mishash Formation that crops out extensively East of Jerusalem (Mount of Olives and surroundings). Father Ruffier probably collected these bones in one of the outcrops of this formation, possibly not very far from where he worked and lived (Saint-Anne Community in Jerusalem). These chalky levels, common in the Middle East, represent a shallow and rather open marine environment, possibly near-shore.


2005 ◽  
Vol 52 ◽  
pp. 141-158
Author(s):  
Stephen R. Packer ◽  
Malcolm B. Hart

A moderately diverse fauna of Late Cretaceous Radiolaria are described for the first time from the Arnager Limestone and Bavnodde Greensand formations exposed on the island of Bornholm (Denmark). Our preliminary investigation suggests that the fauna from the Arnager Limestone Formation is relatively abundant and is assigned to the Orbiculiforma vacaensis Subzone (Alievium praegallowayi Zone) of Coniacian age. Relatively poor recovery from the Bavnodde Greensand Formation precludes assignment to the zonation scheme of Pessagno, although, the radiolarian taxa present indicate that the formation can be no younger than Santonian. The ages given for both formations by the radiolarian faunas compare favourably with published macrofossil and microfossil data. The radiolarian faunas described are of moderate abundance and diversity when compared to contemporaneous faunas described elsewhere, particularly the Tethyan area. Maximum radiolarian abundance and diversity is reached in the middle of the Arnager Limestone Formation equating to a level of maximum water depth from the foraminiferal data. A decline in radiolarian recovery is recognised into the Bavnodde Greensand Formation and is associated with a reduction in relative water depth to inner and (?)middle shelf conditions, as indicated by foraminiferal data.


Author(s):  
I.A. Starodubtseva ◽  
◽  
A.B. Herman ◽  

he paper is devoted to research of the famous paleobotanist and stratigrapher A.N. Kryshtofovich in the Far East. Here he has been formed as a geologist, palaeobotanist and stratigrapher. His discovery of the Late Cretaceous flora in Sakhalin Island and elaboration of the Upper Cretaceous stratigraphy was a sinificant contribution to the world science. His geological researches in the Sakhalin Island provided a base of the further investigation of the continental Upper Cretaceous in the region. In the Far East, A.N. Kryshtofovich collaborated with the famous Far Eastern geologist E.E. Anert. Their correspondence is published here for the first time.


2019 ◽  
Vol 59 (6) ◽  
pp. 1074-1085
Author(s):  
E. A. Sokolova

The article analyzes own data on the species composition of shells of planktonic foraminifera from the Upper Cretaceous sediments of the Indian Oceans, as well as from the sections of the offshore seas of Australia. The species of planktonic foraminifera are grouped and arranged in a climatic series. An analysis of the change in the systematic composition of foraminifers made it possible to distinguish periods of extreme and intermediate climatic states in the Late Cretaceous.


Zootaxa ◽  
2019 ◽  
Vol 4674 (4) ◽  
pp. 482-490 ◽  
Author(s):  
HONGYU LI ◽  
BO WANG ◽  
XINGYUE LIU

The male of Cretaconiopteryx grandis Liu & Lu, 2017, which is the only representative species of the extinct dustywing subfamily Cretaconiopteryginae, is described for the first time from the Upper Cretaceous Burmese amber. The male genitalia, well preserved in the examined specimen, show a number of plesiomorphic characters, which support the sister group relationship between Coniopterygidae and the rest of extant lacewing families. 


Sign in / Sign up

Export Citation Format

Share Document