scholarly journals Multiple Orbitoides d’Orbigny lineages in the Maastrichtian? Data from the Central Sakarya Basin (Turkey) and Arabian Platform successions (Southeastern Turkey and Oman)

2021 ◽  
Vol 140 (1) ◽  
Author(s):  
Ercan Özcan ◽  
Ali Osman Yücel ◽  
Rita Catanzariti ◽  
Sibel Kayğılı ◽  
Aral I. Okay ◽  
...  
Keyword(s):  
Western Europe ◽  
Species Discrimination ◽  
Evolutionary Trends ◽  
Morphometric Data ◽  
Sw Turkey ◽  
Evolutionary Features ◽  
Platform Margin ◽  
Central Turkey ◽  
Upper Maastrichtian ◽  
Arabian Platform

AbstractThe standard reconstruction of species of Orbitoides d’Orbigny into a single lineage during the late Santonian to the end of the Maastrichtian is based upon morphometric data from Western Europe. An irreversible increase in the size of the embryonic apparatus, and the formation of a greater number of epi-embryonic chamberlets (EPC) with time, is regarded as the main evolutionary trends used in species discrimination. However, data from Maastrichtian Orbitoides assemblages from Central Turkey and the Arabian Platform margin (Southeastern Turkey and Oman) are not consistent with this record. The Maastrichtian Besni Formation of the Arabian Platform margin in Southeastern Turkey yields invariably biconvex specimens, with small, tri- to quadrilocular embryons and a small number of EPC, comparable to late Campanian Orbitoides medius (d’Archiac). The upper Maastrichtian Taraklı Formation from the Sakarya Basin of Central Turkey contains two distinct, yet closely associated forms of Orbitoides, easily differentiated by both external and internal features. Flat to biconcave specimens possess a small, tri- to quadrilocular embryonic apparatus of Orbitoides medius-type and a small number of EPC, whereas biconvex specimens possess a large, predominantly bilocular embryonic apparatus, and were assigned to Orbitoides ex. interc. gruenbachensis Papp–apiculatus Schlumberger based on morphometry. The flat to biconcave specimens belong to a long overlooked species Orbitoides pamiri Meriç, originally described from the late Maastrichtian of the Tauride Mountains in SW Turkey. This species is herein interpreted to be an offshoot from the main Orbitoides lineage during the Maastrichtian, as are forms that we term Orbitoides ‘medius’, since they recall this species, yet are younger than normal occurrence with the accepted morphometrically defined lineage. The consistent correlation between the external and internal test features in O. pamiri implies that the shape of the test is not an ecophenotypic variation, but appears to be biologically controlled. We, therefore, postulate that more than one lineage of Orbitoides exists during the Maastrichtian, with a lineage that includes O. ‘medius’ and O. pamiri displaying retrograde evolutionary features.

scholarly journals The relative taxonomic value of morphological characters in the genus <i>Nummulites</i> (Foraminiferida)

1992 ◽  
Vol 11 (2) ◽  
pp. 197-209 ◽  
Author(s):  
Andrew Racey
Keyword(s):  
Morphological Character ◽  
Morphological Characters ◽  
Species Discrimination ◽  
Evolutionary Trends ◽  
Ontogenetic Effects

Abstract. The main evolutionary trends in the nummulites are briefly summarised and the value of certain morphological characters in species discrimination are summarised. The degree of interdependence of each morphological character on all other characters is assessed and the characters are weighted in order of importance. Environmental and ontogenetic effects on each character are then reviewed and the characters reweighted in order of importance.

Significance of Two New Pleistocene Plant Records from Western Europe

2000 ◽  
Vol 54 (2) ◽  
pp. 253-263 ◽  
Author(s):  
Michael H. Field ◽  
Felix Y. Velichkevich ◽  
Valerie Andrieu-Ponel ◽  
Phillipe Woltz
Keyword(s):  
Fossil Record ◽  
Western Europe ◽  
Species Level ◽  
Middle Pleistocene ◽  
Evolutionary Trends ◽  
Plant Macrofossil ◽  
Palynological Assemblages ◽  
Insight Into

The first records of extinct Caulinia goretskyi (Dorofeev) Dorofeev (synonym Najas goretskyi Dorofeev) in western Europe and of Potamogeton occidentalis M.H. Field sp. nov. were obtained from plant macrofossil analyses of Middle Pleistocene temperate stage deposits exposed at Trez Rouz, Brittany, France. Palynological assemblages recovered suggest correlation with the Holsteinian Stage. This discovery greatly expands the western limit of the paleogeographical distribution of Caulinia goretskyi. The record of Potamogeton occidentalis indicates an affinity with the eastern Asiatic flora, as the fruits resemble those of the extant Potamogeton maackianus A. Bennett. Other extinct Pleistocene species related to P. maackianus have been described, and it is possible to follow the development of this group through the Pleistocene in the European fossil record. These new finds illustrate the importance of a complete paleobotanical approach (both plant macrofossil and palynological analyses). The plant macrofossil assemblages not only provide detailed insight into local vegetation and environment, because they are often not transported long distances (in temperate areas) and can frequently be identified to species level; they can also offer the opportunity to investigate Pleistocene evolutionary trends.

scholarly journals Aptian faulting in the Haushi-Huqf (Oman) and the tectonic evolution of the southeast Arabian platform-margin

GeoArabia ◽  
2003 ◽  
Vol 8 (4) ◽  
pp. 643-662 ◽  
Author(s):  
Christian Montenat ◽  
Pascal Barrier ◽  
Henri J. Soudet
Keyword(s):  
Strike Slip ◽  
Coarse Grained ◽  
Normal Faults ◽  
Third Order ◽  
Lower Aptian ◽  
Platform Margin ◽  
Platform Carbonates ◽  
Transform Margin ◽  
Order Sequence ◽  
Arabian Platform

ABSTRACT A major upper Aptian unconformity is recorded on the eastern Arabian Platform, between the lower Aptian Qishn limestone and the Albian Nahr Umr marls. The study of this hiatus, in the western homocline of the Haushi-Huqf Uplift (Eastern Central Oman) provides new data about the evolution of the eastern Arabian Platform during middle Cretaceous times. The limestones of the Qishn formed a shoaling sequence, mainly composed of matrix-rich, coarse-grained sediment with small rudistids and algal build-ups, that led to a subemergent environment. A third-order sequence is recognized in the Qishn platform carbonates, which is partitioned into three minor sequences. The Qishn carbonate was subjected to pre-lithification normal faulting. A thick ferrugineous crust (hardground) covered the top surface of the Qishn as well as the faultscarps before they were buried under the Albian Nahr Umr marls. The faults are dominantly NW-trending, SW-facing, normal faults. The significance of the faulting remains hypothetical. The syndiagenetic NW-SE normal faults may correspond to ‘en-echelon’ faults, combined with a sinistral movement of the Haushi-Nafun Fault (HNF). The HNF acted as a left-lateral, strike-slip fault during late Cretaceous, pre-Maastrichtian times. This movement possibly began earlier, during the late Aptian. It could be related to the dynamics of the eastern Arabian margin during the Cretaceous (Masirah transform margin). There are some indications testifying to the activity of the Masirah transform fault during the early-middle Cretaceous. The margin kinematics may be responsible for the reactivation of nearby large faults affecting the platform basement (for instance the HNF). A slight sinistral reactivation of the HNF may have induced the development of the Aptian NW-trending normal faults. Moreover, the occurrence of early Cretaceous strike-slip movements in the Arabian Platform have already been envisaged, at a plate-scale, as a consequence of the South Atlantic extension. On this assumption, the Aptian fault blocks may have resulted from the development of a sinistral transtension along the HNF.

Paleogene carbonate systems at the Arabian platform margin (Oman)

2001 ◽  
Vol 28 (1) ◽  
pp. 145-148 ◽  
Author(s):  
Philippe Razin ◽  
Jean Roger ◽  
Chantal Bourdillon ◽  
Josep Serra-Kiel ◽  
Jean Philip ◽  
...  
Keyword(s):  
Platform Margin ◽  
Arabian Platform

Integration of molecular, bioacoustical and morphological data reveals two new cryptic species of Pelodytes (Anura, Pelodytidae) from the Iberian Peninsula

Zootaxa ◽  
2017 ◽  
Vol 4243 (1) ◽  
pp. 1 ◽  
Author(s):  
JESÚS DÍAZ-RODRÍGUEZ ◽  
MARCELO GEHARA ◽  
RAFAEL MÁRQUEZ ◽  
MIGUEL VENCES ◽  
HELENA GONÇALVES ◽  
...  
Keyword(s):  
Iberian Peninsula ◽  
Western Europe ◽  
Relative Size ◽  
Morphological Data ◽  
Genetic Admixture ◽  
Species Discrimination ◽  
Rrna Gene ◽  
Species Trees ◽  
Nuclear Markers ◽  
Extant Species

Parsley frogs (Pelodytes) comprise the only genus in the family Pelodytidae, an ancient anuran lineage that split from their closest relatives over 140 million years ago. Pelodytes is a Palearctic group restricted to Western Eurasia including three extant species: the eastern species P. caucasicus, endemic to the Caucasus area, and two closely related species inhabiting Western Europe: the Iberian endemic P. ibericus and the more widespread P. punctatus. Previous studies based on mitochondrial and nuclear DNA markers have revealed the existence of two additional lineages of Parsley frogs in the Iberian Peninsula, which have been flagged as candidate species. Here, we integrate novel molecular, morphological and bioacoustical data to assess the differentiation of the four western Parsley frog lineages. Species trees and Bayesian population assignment analyses based on nuclear markers confirm previous studies and concordantly delineate four parapatric lineages with narrow hybrid zones. Mitochondrial divergence is low (< 2% pairwise distances in the 16S rRNA gene), in line with previously reported low mitochondrial substitution rates in non-neobatrachian frogs. Based on concordance between mitochondrial and nuclear markers, we conclude that four species of Parsley frogs occur in Western Europe: Pelodytes punctatus, distributed from northern Italy to northeastern Spain; Pelodytes ibericus, inhabiting southern Spain and southern Portugal; Pelodytes atlanticus sp. nov., from the Portuguese Atlantic coast; and Pelodytes hespericus sp. nov., occurring in central and eastern Spain. However, bioacoustical and morphological differentiation of these species is low, with no obvious and qualitative diagnostic characters allowing full species discrimination. Differences in the relative size of metacarpal tubercles exist but this character is variable. Pelodytes ibericus and Pelodytes atlanticus are smaller than the other two species, and P. ibericus has shorter limbs and various distinctive osteological characters. Bioacoustically, the pattern by which two different note types are combined in advertisement calls separates P. hespericus from the remaining species. Despite these differences, we emphasize that the taxonomic status of all four western Parsley frogs requires additional investigation, especially the patterns of genetic admixture across contact zones. While a status of separate species best conforms to the currently available data, alternative hypotheses are also discussed. 

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