The genera Lepidorbitoides and Orbitcoides: evolution and stratigraphic significance in some Anatolian basins

Date

1999-07-01

Author

ÖZCAN, ERCAN
Altıner, Sevinç

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

116
views

0
downloads

Early ontogenetic morphologic features previously recognized as evolutionary parameters in Lepidorbitoides and Orbitoides have been tested in several flysch successions of Anatolia. Increase in embryo size (Li + ii), number of epi-embryonic chambers (E) and organization of embryonal chamber arrangement from 'quadrilocular' to 'bilocular' and multilocular in Orbitoides, increase in deuteroconch size (D), in deuteroconch-protoconch ratio (D/P) and in number of adauxiliary chambers (Ad) in Lepidorbitoides have been recognized as the main evolutionary trends, thus allowing the correlation of these features with time. The different developmental stages in Lepidorbitoides, i.e. L. pembergeri, L. campaniensis, L. bisambergensis, L. minor, L. socialis, and in Orbitoides, i.e. O. media, O. megaloformis, O. gruenbachensis, O. apiculata and O. gensacicus, have been described and illustrated based on the biometry of the populations. The values observed in some horizons, however, may not reflect the true phylogenetic stage of the orbitoidal taxa, especially in the species of Orbitoides, which usually show a wide variation of evolutionary parameters in the same population. A correlation scheme of phylogenetic development in Lepidorbitoides and Orbitoides with the planktonic foraminiferal zones is proposed. Lepidorbitoides populations with highly asymmetric 'quadriserial' nepionts occurring stratigraphically below the symmetric ones in Early Maastrichtian are thought to deserve a particular taxonomic status. In Orbitoides, a new embryonal chamber morphology previously undescribed from horizontal sections has been discovered. Copyright (C) 1999 John Wiley & Sons, Ltd.

Subject Keywords

Lepidorbitoides, Orbitoides, Early ontogeny, Biometry, Biostratigraphy, Plankton-benthos correlation, Late Cretaceous, Anatolia, Turkey

URI

https://hdl.handle.net/11511/53899

Journal

GEOLOGICAL JOURNAL

Collections

Department of Geological Engineering, Article

Suggestions

OpenMETU
Core

An expanded molecular phylogeny of Plumbaginaceae, with emphasis on Limonium (sea lavenders): Taxonomic implications and biogeographic considerations Koutroumpa, Konstantina; Theodoridis, Spyros; Warren, Ben H.; Jimenez, Ares; Celep, Ferhat; Doğan, Musa; Romeiras, Maria M.; Santos-Guerra, Arnoldo; Maria Fernandez-Palacios, Jose; Caujape-Castells, Juli; Moura, Monica; de Sequeira, Miguel Menezes; Conti, Elena (Wiley, 2018-12-01) Plumbaginaceae is characterized by a history of multiple taxonomic rearrangements and lacks a broad molecular phylogenetic framework. Limonium is the most species-rich genus of the family with ca. 600 species and cosmopolitan distribution. Its center of diversity is the Mediterranean region, where ca. 70% of all Limonium species are endemic. In this study, we sample 201 Limonium species covering all described infrageneric entities and spanning its wide geographic range, along with 64 species of other Plumba...
The relationship between genetic and shape variation in endemic and endangered freshwater fish species pseudophoxinus Telli, Murat; Kence, Aykut; Department of Biology (2008) Evolutionary models addressing interaction between genetics and morphology propose that during development, morphological traits of organisms are under canalization selection resulting in constancy in morphology through evolutionary time. The hypothesis of genetic homeostasis predict that because of developmental buffering effects of heterosis, high level heterozygosity results in low level of morphological variance from the norms of canalized shape of the population. The aim of the present study is to test...
Description of an early ontogenetic evolutionary step in Lepidorbitoides Lepidorbitoides bisambergensis asymmetrica subsp n Early Maastrichtian central Turkey ÖZCAN, ERCAN; Altıner, Sevinç (2001-01-01) Lepidorbitoides bisambergensis is characterised by having a 'quadriserial' embryo without any chamberlet directly arising from the deuteroconch and is a very diagnostic and common species in Lower Maastrichtian flysch successions in Anatolia. Some populations of this species present an early ontogenetic morphologic feature which is characterised by distinctly asymmetric early chamber arrangement recognised in the horizontal sections. This asymmetry is mainly caused by the pronounced difference in the size o...
The Role of Top-Down and Bottom-Up Control for Phytoplankton in a Subtropical Shallow Eutrophic Lake: Evidence Based on Long-Term Monitoring and Modeling Mao, Zhigang; Gu, Xiaohong; Cao, Yong; Zhang, Min; Zeng, Qingfei; Chen, Huihui; Shen, Ruijie; Jeppesen, Erik (Springer Science and Business Media LLC, 2020-02-03) Lake ecosystems are exposed to a range of anthropogenic pressures, particularly eutrophication, and in some cases also stocking and/or overfishing of top-predator fish species, all factors that have implications for the food web structure and which could lead to dominance of nuisance cyanobacteria. Restoration of degraded lakes demands insight into the relative role of top-down for bottom-up regulating forces. While knowledge about these forces in temperate lakes is extensive, comparatively little is known ...
Early gene expression divergence between allopatric populations of the house mouse (Mus musculus domesticus) Bryk, Jaroslaw; Somel, Mehmet; Lorenc, Anna; Teschke, Meike (Wiley, 2013-03-01) Divergence of gene expression is known to contribute to the differentiation and separation of populations and species, although the dynamics of this process in early stages of population divergence remains unclear. We analyzed gene expression differences in three organs (brain, liver, and testis) between two natural populations of Mus musculus domesticus that have been separated for at most 3000years. We used two different microarray platforms to corroborate the results at a large scale and identified hundr...

Citation Formats

E. ÖZCAN and S. Altıner, “The genera Lepidorbitoides and Orbitcoides: evolution and stratigraphic significance in some Anatolian basins,” GEOLOGICAL JOURNAL, pp. 275–286, 1999, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/53899.