scholarly journals Report on the Discovery of Fossil Mares with Preserved Uteroplacenta from the Eocene of Germany

2017 ◽  
Vol 73 (1-2) ◽  
pp. 67-75
Author(s):  
Jens Lorenz Franzen
Keyword(s):  
Middle Eocene ◽  
The Other ◽  
Late Mesozoic ◽  
Eifel Mountains

I report on the discoveries of three pregnant mares from the middle Eocene of Germany that contain remains of fetuses still wrapped in the fossilized uteroplacenta. These are the first and up to now only discoveries of this kind. One specimen comes from the Eckfeld Maar (Eifel Mountains). It is 44 million years of age. The other two were discovered at Grube Messel and are 48 million years old. These are the oldest fossil uteroplacentae known so far. Their morphology corresponds to recent homologues. Presumably, the uteroplacenta developed as part of the propagation system of mammals during the Palaeocene, perhaps already during the late Mesozoic.

Is predation intensity reduced with increasing depth? Evidence from the west Atlantic stalked crinoidEndoxocrinus parrae(Gervais) and implications for the Mesozoic marine revolution

Paleobiology ◽  
1996 ◽  
Vol 22 (3) ◽  
pp. 339-351 ◽  
Author(s):  
Tatsuo Oji
Keyword(s):  
Shallow Water ◽  
The Other ◽  
The West ◽  
Bathymetric Range ◽  
Late Mesozoic ◽  
Predation Intensity ◽  
Stalked Crinoids ◽  
The Caribbean ◽  
Mesozoic Marine Revolution ◽  
Sublethal Predation

The number of regenerated arms was counted on specimens of two distinct phenotypes of the stalked crinoidEndoxocrinus parrae(Gervais) from a wide bathymetric range in the Caribbean (178-723 m). In one phenotype, the sample was divided into two groups, one from shallower (< 500 m) depths, the other from deeper (≥ 500 m); in the other phenotype the group divided at 550 m. In both phenotypes, the frequency of regenerated arms is significantly higher in specimens from shallower water than in those from deeper water. If the regenerated arms inEndoxocrinus parraewere the result of sublethal predation, as previously suggested, then predation intensity is higher in shallow water than deep water. These results are consistent with the idea of the late Mesozoic marine revolution—that there has been stronger predation on various invertebrates in shallow-water environments since the late Mesozoic. The stalked crinoids may have been unable to cope with increased predation in shelf environments, and they migrated to offshore environments.

scholarly journals New or previously unrecorded avian taxa from the Middle Eocene of Messel (Hessen, Germany)

Fossil Record ◽  
2000 ◽  
Vol 3 (1) ◽  
pp. 207-219 ◽  
Author(s):  
G. Mayr
Keyword(s):  
Middle Eocene ◽  
The Other ◽  
New Taxon ◽  
New Information ◽  
Wenn Sich

Three new or from this site previously unrecorded birds are described from the Middle Eocene of Messel (Hessen, Germany). <i>Serudaptus pohli</i> n. gen. n. sp. is a new taxon of the Pseudasturidae and is distinguished from the other species of this family by its short and stout tarsometatarsus and the long and strong claws. An isolated foot of a gruiform bird is assigned to <i>Idiornis</i> cf. <i>itardiensis</i> (Idiornithidae) and would, if this assignment can be confirmed, demonstrate the existence of this species for a period of 23 million years. The proportions of the toes suggest that <i>Idiornis</i> cf. <i>itardiensis</i> was less cursorial than its next recent relatives, the Cariamidae. In addition thereto, an exceptionally well preserved skeleton of a sandcoleid bird (Coliiformes: Sandcoleidae) gives new information on the osteology and feathering of sandcoleid birds. The specimen resembles the genera <i>Eoglaucidium</i> and <i>Anneavis</i> but it has not been possible to assign it to one of these two genera with certainty. <br><br> Drei neue oder von dieser Fundstelle bisher nicht nachgewiesene Vögel werden aus dem Mittel-Eozän von Messel (Hessen, Deutschland) beschrieben. <i>Serudaptus pohli</i> n. gen. n. sp. ist ein neues Taxon der Pseudasturidae und unterscheidet sich von den anderen Arten dieser Familie durch den kurzen und gedrungenen Tarsometatarsus und die langen, kräftigen Krallen. Der isolierte Fuß eines gruiformen Vogels wird <i>Idiornis</i> cf. <i>itardiensis</i> (Idiornithidae) zugeordnet und würde, wenn sich diese Zuordnung bestätigt, die Existenz dieser Art über einen Zeitraum von 23 Millionen Jahren zeigen. Die Zehenproportionen legen nahe, dass <i>Idiornis</i> cf. <i>itardiensis</i> weniger an eine laufende Lebensweise angepasst war als seine nächsten rezenten Verwandten, die Cariamidae. Darüber hinaus zeigt ein außergewöhnlich gut erhaltenes Skelett eines Vertreters der Sandcoleidae bisher unbekannte Einzelheiten der Osteologie und Befiederung dieser Familie. Das Exemplar ähnelt den Gattungen <i>Eoglaucidium</i> und <i>Anneavis</i>, konnte jedoch keiner der beiden Gattungen mit Sicherheit zugeordnet werden. <br><br> doi:<a href="http://dx.doi.org/10.1002/mmng.20000030110" target="_blank">10.1002/mmng.20000030110</a>

A new hoverfly genus and species from the middle Eocene Baltic amber (Diptera: Syrphidae)

2020 ◽  
Vol 3 (1) ◽  
pp. 068-075
Author(s):  
VALÉRIE NGÔ-MULLER ◽  
ANDRÉ NEL
Keyword(s):  
Late Cretaceous ◽  
Fossil Record ◽  
New Genus ◽  
Middle Eocene ◽  
The Other ◽  
Baltic Amber ◽  
New Genus And Species ◽  
Stem Lineage ◽  
Syrphid Flies ◽  
The Baltic

Syrphid flies are an important clade of pollinators, and predators on several insect groups. The oldest record of its stem lineage is late Cretaceous, but this family really diversified during the Eocene-Oligocene, with a rather sparse fossil record. Here we describe from the Baltic amber the new genus and species Eoxanthandrus garroustei gen. et sp. nov., the first fossil representative of the Syrphinae ‘group’ Bacchini and Melanostomini. Its closest extant relatives prey on caterpillars, while the other Syrphinae generally prey on Hemiptera. This specialized biology possibly dates back to the middle Eocene.

Waidelotinae, a new subfamily of Pyrochroidae (Coleoptera: Tenebrionoidea) from Baltic amber of the Sambian peninsula and the interpretation of Sambian amber stratigraphy, age and location

Zootaxa ◽  
2019 ◽  
Vol 4664 (2) ◽  
pp. 261-273 ◽  
Author(s):  
ANDRIS BUKEJS ◽  
VITALII I. ALEKSEEV ◽  
DARREN A. POLLOCK
Keyword(s):  
Middle Eocene ◽  
The Other ◽  
Baltic Amber ◽  
Central European ◽  
Basal Half

Waidelotus hoffeinsorum gen. et sp. nov. is described from Eocene Baltic amber and assigned to Waidelotinae subfam. nov. within family Pyrochroidae (Coleoptera). The new subfamily differs from the other subfamilies by the following combination of features: penultimate tarsomere of all tarsi deeply bilobed, antepenultimate tarsomere of each pro- and mesothoracic tarsus slightly bilobed, antepenultimate tarsomere of metathoracic tarsi slightly widened apically; pronotum laterally margined in basal half; eyes emarginate; pretarsal claws appendiculate; prosternal intercoxal process incompletely separating prothoracic coxae; pronotum with fine posterior submarginal groove; head without distinct constriction behind eyes; posterior pronotal pits absent; and elytral pubescence homogenous. It is the only authentic species of Pyrochroidae (Coleoptera) from Baltic amber, pending final placement of Palaeopyrochroa crowsoni Abdullah, 1965. Additionally, the available data on stratigraphy of amber-bearing strata on the Sambian peninsula, and the age and location of Eocene amberiferous forests are discussed. A middle Eocene (mostly Bartonian) age is interpreted for the extinct Central European resin-producing forests resulting in the Sambian amber deposits. 

III.—Eocene Echinoids from Sokoto

1904 ◽  
Vol 1 (7) ◽  
pp. 292-304 ◽  
Author(s):  
F. A. Bather
Keyword(s):  
Solid Rock ◽  
Middle Eocene ◽  
British Museum ◽  
The Other ◽  
The Matrix ◽  
Rock Specimens

It is fortunate that Captain Lelean not merely discovered these fossils at Garadimi in Sokoto, but that he had enough sense of their importance to spend some time and trouble in their collection, and that now he has generously presented them to the British Museum. The collection includes four echinoid tests, five natural casts of Mollusca, and a few rock-specimens containing Operculina and other Foraminifera. The Mollusca, so far as their state of preservation admits, have been determined by Mr. R. Bullen Newton as: 3 Lucina cf. gigantea Deshayes, 1 Voluta cf. cithara Lamarck, and 1 undetermined Gastropod. The Echinoidea were partly covered by an impure limestone closely adherent to the test. The portions not so covered were in many places considerably worn, and the calcite was split by cracks, probably due to alternations of temperature, and rendering it very difficult to follow the course of the sutures. The appearance of these and the other specimens shows clearly that they have been lying on the surface of the ground for some time, and, in fact, Captain Lelean informs me that they were not picked out of the solid rock, but from the talus at the foot of the cliff. The notable variations in the matrix of the different specimens are thus accounted for. None the less it will be seen in the sequel that all the specimens are consistent with the ascription of a Middle Eocene age to the mass of limestone from which they were derived. Of the four echinoids, two have been determined as belonging to the genus Plesiolampas and two to the genus Hemiaster.

scholarly journals A new Late Eocene primate from the Krabi Basin (Thailand) and the diversity of Palaeogene anthropoids in southeast Asia

2013 ◽  
Vol 280 (1771) ◽  
pp. 20132268 ◽  
Author(s):  
Yaowalak Chaimanee ◽  
Olivier Chavasseau ◽  
Vincent Lazzari ◽  
Adélaïde Euriat ◽  
Jean-Jacques Jaeger
Keyword(s):  
Phylogenetic Relationships ◽  
Evolutionary History ◽  
Middle Eocene ◽  
Late Eocene ◽  
The Other ◽  
Crown Group ◽  
Phylogenetic Relations ◽  
Stem Group ◽  
Morphological Adaptations ◽  
Anthropoid Primates

According to the most recent discoveries from the Middle Eocene of Myanmar and China, anthropoid primates originated in Asia rather than in Africa, as was previously considered. But the Asian Palaeogene anthropoid community remains poorly known and inadequately sampled, being represented only from China, Myanmar, Pakistan and Thailand. Asian Eocene anthropoids can be divided into two distinct groups, the stem group eosimiiforms and the possible crown group amphipithecids, but the phylogenetic relationships between these two groups are not well understood. Therefore, it is critical to understand their evolutionary history and relationships by finding additional fossil taxa. Here, we describe a new small-sized fossil anthropoid primate from the Late Eocene Krabi locality in Thailand, Krabia minuta , which shares several derived characters with the amphipithecids. It displays several unique dental characters, such as extreme bunodonty and reduced trigon surface area, that have never been observed in other Eocene Asian anthropoids. These features indicate that morphological adaptations were more diversified among amphipithecids than was previously expected, and raises the problem of the phylogenetic relations between the crown anthropoids and their stem group eosimiiforms, on one side, and the modern anthropoids, on the other side.

scholarly journals Fossil mammals from the central Chilean Andes: a new interval in the South American land mammal succession, and implications for Eocene-Oligocene boundary events and Andean tectonics

1992 ◽  
Vol 6 ◽  
pp. 318-318 ◽  
Author(s):  
A.R. Wyss ◽  
J.J. Flynn ◽  
C.C. Swisher ◽  
R. Charrier ◽  
M.A. Norell
Keyword(s):  
Late Cretaceous ◽  
Middle Eocene ◽  
South American ◽  
Mammalian Fauna ◽  
Late Mesozoic ◽  
The Andes ◽  
Early Tertiary ◽  
Tectonic Rotation ◽  
Land Mammal ◽  
Mammal Faunas

Biostratigraphically significant samples have been collected from six localities in post-Neocomian terrestrial deposits of the central Andean Main Range (34° 50 S latitude), Chile. Localities are distributed over an area of 13 km by 5 km, and span more than 2500 m of section.Two eastern localities occurring lowest in the sequence yield a diverse suite of more than 20 taxa indicative of a new biochronologic interval between the Mustersan (?middle Eocene) and Deseadan (?late Oligocene-early Miocene) South American Land Mammal Ages (LMA); speculatively it also is older than the enigmatic Divisideran “LMA”. Noteworthy occurrences include the first South American appearance of rodents, argyrolagoid marsupials, and interatheriine interathere and advanced notohippid Notoungulata, as well as the last appearance of polydolopid marsupials, and notopithicine and notostylopid Notoungulata. Four K-Ar and Ar40-Ar39 analyses on a flow and tuff which directly underlie one locality yield ages between 35.6 ± 0.9 and 37.56 ± 0.14 Ma; the fossiliferous unit itself has produced four Ar40-Ar39 dates between 31.7 ± 0.3 and 31.37 ± 0.08 Ma in one locality. Therefore, the new biochronologic interval appears to be earliest Oligocene in age, and is the oldest sequence representing Simpson's “Second Faunal Stratum”. The “Tinguiririca” assemblage is the oldest South American mammalian fauna dominated by herbivores (in a diversity of taxa) with high-crowned or evergrowing teeth, documenting major changes caused by interaction between a major phase of tectonic uplift in the central Andes and global climatic changes near the Eocene-Oligocene boundary.We recently recovered about one dozen skulls and jaws from several sites some 10 km west of, and 2500 m stratigraphically above, these lowest localities. The fauna from these new western sites appears advanced over the localities to the east, and probably is younger than about 20 Ma, based on stratigraphy and Ar40-Ar39 dates from units overlying the eastern localities. The new faunas should help resolve controversy concerning the younger limit of the Deseadan LMA.Discovery of the mammal faunas has profoundly altered understanding of central Andean geology: 1) we identified an unconformity between Jurassic marine/late Cretaceous clastic units and volcaniclastic mid-Tertiary deposits, indicating that a dramatic episode of volcanism previously attributed to the late Mesozoic is in fact 30 m.y. younger; 2) consequently, the late Cretaceous/early Tertiary is characterized by non-deposition or erosion, rather than by volcanic deposition as had been hypothesized earlier; and 3) our paleomagnetic results also indicate previously unrecognized, but significant post-Miocene clockwise tectonic rotation (up to 20°) of units in this part of the Andes.

scholarly journals The lignite of tracey

1910 ◽  
Vol 82 (560) ◽  
pp. 650-650
Keyword(s):  
Middle Eocene ◽  
The Other ◽  
Geological Survey ◽  
Isle Of Wight ◽  
Geological Record ◽  
Lower Miocene ◽  
Upper Miocene ◽  
Upper Oligocene

In 1863, Heer and Pengelly published in the ‘Phil. Trans.’ an account of these lignite-beds and their flora. Heer classed the lignite as Lower Miocene, considering it equivalent to the Aquitanian of Prance and to the Hamstead Beds of the Isle of Wight. These latter are now referred to the Middle Oligocene, and many of the other deposits called Lower Miocene in Heer’s day are now classed as Upper Oligocene. A statement by Mr. Starkie Gardner, that Heer’s Bovey plants are the same as those found in the Bournemouth Beds (Middle Eocene), has caused the Bovey Beds to be classed as Eocene in recent text-books and on recent maps of the Geological Survey, leaving a great gap in the geological record in Britain. Every division, from Upper Oligocene to Upper Miocene, was supposed to be missing.

Correlation of plume morphologies on joint surfaces with their fracture mechanic implications

2008 ◽  
Vol 145 (5) ◽  
pp. 733-744 ◽  
Author(s):  
D. BAHAT ◽  
A. RABINOVITCH ◽  
V. FRID
Keyword(s):  
New York ◽  
Middle Eocene ◽  
The Other ◽  
Lower Eocene ◽  
Beer Sheva ◽  
Appalachian Plateau ◽  
Joint Surfaces ◽  
End Members ◽  
Fracture Velocity ◽  
Slow Propagation

AbstractThe fractography and conditions of propagation of joints that cut Devonian siltstones in the Appalachian Plateau, New York, and Eocene chalks from the Beer Sheva Syncline, Israel, are investigated. The joints cutting the siltstones are marked by S-type and C-type plumes, and the joints cutting the Lower Eocene and Middle Eocene chalks are marked by coarse and delicate plumes, respectively. The four plume types propagated under sub-critical (slow propagation) conditions. On the semi-quantitative fracture velocity (v) versus the tensile stress intensity (KI) curves, the S and C plume types fall in the KI=0.073–0.79 MPa m1/2 and v=2×10−4–10−2 m/s and KI=0.073–0.79 MPa m1/2 and v=10−6–10−4 m/s ranges respectively. The coarse and delicate plumes fall in the KI=0.03–0.17 MPa m1/2 and v=10−6–4×10−5 m/s and KI=0.03–0.17 MPa m1/2 and v=10−4–5×10−3 m/s ranges, respectively. Generally, slow plumes are relatively short, show periodicity, and typically exhibit superposition of arrest marks. On the other hand, faster plumes are longer and continuous, occur particularly in thinner layers, and show no superposition of arrest marks. There is a clear distinction between two en échelon segmentation end-members in the joint fringe, the ‘discontinuous breakdown type’ and the ‘continuous breakdown type’. There are also ‘transitional’ variations between the end-members. Only curved ‘discontinuous breakdown type’ boundaries of en échelon fringes can be equated with mirror boundaries.

scholarly journals Sedimentary Basin Reconstruction and Tectonic Development of Paleocene-Eocene Succession, Southern Iraq, by Geohistory Analysis

2021 ◽  
pp. 1213-1225
Author(s):  
Mahdi Ali Menshed ◽  
Aiad Ali Hussien Al-Zaidy
Keyword(s):  
Middle Eocene ◽  
Late Eocene ◽  
Oil Field ◽  
Transitional Period ◽  
The Other ◽  
Arabian Plate ◽  
The West ◽  
Tectonic Lineament ◽  
Western Side ◽  
Tectonic Boundary

The Paleocene-Early Eocene sequence is represented by Aliji and Umm Er Radhuma formations, while the Middle-Late Eocene sequence is represented by Jaddala and Dammam formations. The Rus Formation has been described and its basin was analyzed separately because it was deposited during the regression period (Middle Eocene), which is a transitional period between these two cycles.   This study includes analysis of the geohistory of this succession,  interpretation of the changes of the accumulation, and calculation of subsidence rates. The results were compared with the space available to explain the basin development. The study site included the boreholes of Garraf-84 and 92, Halfaya-1, Nasirya-13 and 40, and Noor-5 at the Mesopotamian Block, in addition to the  Ratawi-8, Tuba-15, Rumaila-217, Zubair-45, and West Qurna-60 at the Basra Block.      The Aliji basin was characterized by the decrease in accommodation values to the northeast direction and the increase in all the other parts of the study area. A comparison of the setting of this basin with the Umm Er Radhuma basin gives a clear evidence of the tectonic impact coming from the northeast. During the Middle Eocene stage, we notice that the basin was affected by comprehensive uplifting processes. This led to the generation of a very shallow basin (Rus basin) with the exposure of the northern part of the basin during the regression stage.      The Middle-Late Eocene basin is represented by a transgression stage with high subsidence, where the sea level had been raised and covered the northeastern and eastern parts of the studied area by deep sea deposits (Jaddala Formation). While the other parts of the study area were characterized by shallow sediments of Dammam Formation. This period ended with a clear tectonic uplift occurring in the northeastern parts and decreasing towards the southwest. This confirms the reactivation of the tectonic action from the northeast, represented by the continental collision. All these sources of evidence indicate that the study area is divided into a northern part and a southern part. Both of these parts are separated by a major tectonic lineament extending from the West Qurna oil field to the Nasiriya oil field, which confirms the presence of the tectonic boundary between the Mesopotamian block and the Basra block. In addition, there exists a secondary tectonic boundary that divides the Mesopotamian block into two parts, the first is to the east and the other is to the west. The results showed that the eastern side was most affected by the collision of the Iranian Plate with the Arabian Plate, which led to its uplift, while the western side was less affected by this tectonics evidence.

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