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First Discovery of Cucubalus (Caryophyllaceae) Fossil, and Its Biogeographical and Ecological ImplicationsHuang, Yong Jiang, Liu, Yu Sheng, Jacques, Frédéric M.B., Su, Tao, Xing, Yaowu, Zhou, Zhekun 05 March 2013 (has links)
A new species of Cucubalus is described based on two fossil seeds recovered from the upper Pliocene Sanying Formation in northwestern Yunnan Province, southwestern China. The seeds are characterized by a reniform to circular outline in shape, and sinuous and discontinuous rugulae made of rod-like elements radiating from the hilum region to the dorsal margin. The combination of these characteristics shows their close resemblance to the extant genus Cucubalus in the Caryophyllaceae. A morphological principal coordinates (PCO) analysis further supports the assignment to this genus. Cucubalus is a monotypic genus today, but the late Pliocene fossil seeds have been described as a new species, Cucubalus prebaccifer Huang, Liu et Zhou, sp. nov. This newly documented Cucubalus fossil, representing the first fossil record of this genus, implies that the genus has existed in northwestern Yunnan, southwestern China, at least since the late Pliocene. It provides important information on the past biodiversity and biogeography of both the genus Cucubalus and the fossil-scant family Caryophyllaceae.
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First Discovery of Cucubalus (Caryophyllaceae) Fossil, and Its Biogeographical and Ecological ImplicationsHuang, Yong Jiang, Liu, Yu Sheng, Jacques, Frédéric M.B., Su, Tao, Xing, Yaowu, Zhou, Zhekun 05 March 2013 (has links)
A new species of Cucubalus is described based on two fossil seeds recovered from the upper Pliocene Sanying Formation in northwestern Yunnan Province, southwestern China. The seeds are characterized by a reniform to circular outline in shape, and sinuous and discontinuous rugulae made of rod-like elements radiating from the hilum region to the dorsal margin. The combination of these characteristics shows their close resemblance to the extant genus Cucubalus in the Caryophyllaceae. A morphological principal coordinates (PCO) analysis further supports the assignment to this genus. Cucubalus is a monotypic genus today, but the late Pliocene fossil seeds have been described as a new species, Cucubalus prebaccifer Huang, Liu et Zhou, sp. nov. This newly documented Cucubalus fossil, representing the first fossil record of this genus, implies that the genus has existed in northwestern Yunnan, southwestern China, at least since the late Pliocene. It provides important information on the past biodiversity and biogeography of both the genus Cucubalus and the fossil-scant family Caryophyllaceae.
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A New Species of Rhodoleia (Hamamelidaceae) From the Upper Pliocene of West Yunnan, China and Comments on Phytogeography and Insect HerbivoryWu, Jingyu, Zhao, Zhenrui, Li, Qijia, Liu, Yusheng, Xie, Sanping, Ding, Suting, Sun, Bainian 01 October 2015 (has links)
In Europe, fossil fruits and seeds of Rhodoleia (Hamamelidaceae) have been described from the Upper Cretaceous to the Miocene, whereas no fossil record of Rhodoleia has been reported in Asia, where the modern species occur. Herein, 21 fossil leaves identified as Rhodoleia tengchongensis sp. nov. are described from the Upper Pliocene of Tengchong County, Yunnan Province, Southwest China. The fossils exhibit elliptic lamina with entire margins, simple brochidodromous major secondary veins, mixed percurrent intercostal tertiary veins, and looped exterior tertiaries. The leaf cuticle is characterized by pentagonal or hexagonal cells, stellate multicellular trichomes, and paracytic stomata. The combination of leaf architecture and cuticular characteristics suggests that the fossil leaves should be classified into the genus Rhodoleia. The fossil distributions indicate that the genus Rhodoleia might originate from Central Europe, and that migrated to Asia prior to the Late Pliocene. Additionally, insect damage is investigated, and different types of damage, such as hole feeding, margin feeding, surface feeding, and galling, are observed on the thirteen fossil leaves. Based on the damage frequencies for the fossil and extant leaves, the specific feeding behavior of insects on Rhodoleia trees appears to have been established as early as the Late Pliocene. The high occurrence of Rhodoleia insect herbivory may attract the insect-foraging birds, thereby increasing the probability of pollination.
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First Mio-Pliocene Salamander Fossil Assemblage From the Southern AppalachiansBoardman, Grant S., Schubert, Blaine W. 06 July 2011 (has links) (PDF)
The Gray Fossil Site (GFS) of northeastern Tennessee has yielded a diverse salamander fossil assemblage for the southern Appalachian Mio-Pliocene. This assemblage includes at least five taxa (Ambsytoma sp.; Plethodon sp., Spelerpinae, gen. et sp. indet., Desmognathus sp.; and Notophthalmus sp.) from three families (Ambystomatidae, Plethodontidae, and Salamandridae, respectively). All taxa are present in the area today and support a woodland-pond interpretation of the site. Reported specimens represent the earliest record of their families in the Appalachian Mountains (and the earliest record of Plethodontidae and Ambystomatidae east of the Mississippi River); with the Notophthalmus sp. vertebrae being the only Mio-Pliocene body fossil known for the Salamandridae in North America. The Desmognathus sp. specimens may help shed light on the evolutionary origins of the genus Desmognathus, which purportedly has its roots in this region during the Mio-Pliocene.
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A New Drynaria (Polypodiaceae) From the Upper Pliocene of Southwest ChinaSu, Tao, Jacques, Frédéric M.B., Liu, Yu Sheng (Christopher), Xiang, Jianying, Xing, Yaowu, Huang, Yongjiang, Zhou, Zhekun 01 February 2011 (has links)
A polypodiaceous fern, Drynaria callispora sp. nov., is described from the upper Pliocene Sanying Formation in western Yunnan Province, southwestern China. This species with well-preserved pinnae and in situ spores is the first convincing Drynaria fossil record. Detailed morphological investigation reveals that D. callispora is characterized by 1) pinnatifid fronds with entire-margined pinnae having straight or zigzag secondary veins; 2) finer venation showing void quadrangular areoles, but occasionally with one unbranched veinlet; 3) one row of circular sori on each side of the strong primary vein; and 4) in situ spores with verrucate exospores elliptical in polar view and bean-shaped in equatorial view. A morphological comparison shows that D. callispora is significantly different from all the fossil species previously identified as drynarioids. A phylogenetic analysis of D. callispora supports that the fossil is closely related to D. sinica Diels and D. mollis Bedd., two extant species distributing in the Himalayas. The discovery of the new fern indicates that the genus Drynaria became diversified in its modern distribution region no later than the late Pliocene and had retained a similar ecology to that of many modern drynarioid ferns ever since.
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Late Neogene Paleoclimate and Paleoenvironment Reconstructions From the Pipe Creek Sinkhole, Indiana, USAShunk, Aaron J., Driese, Steven G., Farlow, James O., Zavada, Michael S., Zobaa, Mohamed K. 15 April 2009 (has links)
The Late Neogene represents warm Earth conditions immediately prior to the development of extensive northern hemisphere glaciation, and this period in Earth history may therefore provide the best available analog for the projected outcome of continued global warming. There are few interior continental sites of Late Neogene age from the eastern half of North America and subsequently very little is known about the conditions characterizing climate. The Early Pliocene (~ 5 Ma) Pipe Creek Sinkhole (PCS) includes the sediment fill of a complex karst environment that developed in north-central Indiana, USA (Lat. 40° 27′ 25.4″, Long. 85° 47′ 37.2″). The site includes more than 3 m of high-chroma, red-colored silty-clay sediment interpreted to be terra rossa. The terra rossa δ13C values average - 20 ± 0.7‰ PDB and are interpreted to represent sediment deposited in a closed cave system under high summer temperatures and with well-drained soils. An in-situ paleosol at the top of the terra rossa represents a transition from a closed cave to an open environment that eventually flooded, thereby becoming a small pond. δ13C values from lacustrine sediments with organic matter derived dominantly from algae average - 20.6‰ and suggest the pond was stagnant and enriched with bicarbonate from the underlying limestones or via aquifers. Pond sediments include abundant vertebrate fossils, which are broadly consistent with those inhabiting an open ecosystem such as a savannah or parkland. However, the PCS pollen includes low taxonomic diversity that is dominated by pine with some hickory and flowering plants, but no grass pollen. We propose two hypotheses to explain the PCS stratigraphic record: (1) The pollen assemblage may represent a local pine dominated ecosystem associated with the pond paleoenvironment, such as a riparian community, and that the greater landscape was drier and open; (2) Alternatively, the climate may have became wetter raising the elevation of the groundwater table and initiating the formation of the pond. Then in response to the wetter conditions an early succession forest ecosystem developed.
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A New Species of Exbucklandia (Hamamelidaceae) From the Pliocene of China and Its Paleoclimatic SignificanceWu, Jingyu, Sun, Bainian, Liu, Yu Sheng, Xie, Sanping, Lin, Zhicheng 01 May 2009 (has links)
Eight fossil leaves identified as Exbucklandia tengchongensis sp. nov. (Hamamelidaceae) were collected from the Pliocene Mangbang Formation in Tengchong, Yunnan Province, Southwest China. The fossil leaves are characterized by the overall rounded lamina with entire margin, actinodromous venation, and cyclocytic stomata, which suggest the affinity within the genus Exbucklandia, particularly with E. populnea. A survey on the cuticles of the sun and shade leaves of modern E. populnea indicates that the shade leaves generally possess more pronounced undulate anticlinal cell walls and a much lower stomatal density than the sun leaves. Two morphotypes, i.e. sun vs. shade types, of the fossil leaves were therefore recognized. The distribution of the modern Exbucklandia suggests that the genus lives under a warm climate with a mean annual temperature (MAT) from 13 °C to 27 °C and a mean annual precipitation (MAP) from 800 mm to 2500 mm. Hence, E. tengchongensis might also live under a similar climatic condition in the Pliocene. Leaf margin analysis on the Tengchong flora supports this result. The little change of Neogene MAT in Southwest China is therefore supported.
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A Dental Microwear Texture Analysis of the Early Pliocene African Ursid Agriotherium africanum (Mammalia, Carnivora, Ursidae)Stynder, Deano D., DeSantis, Larisa R.G., Donohue, Shelly L., Schubert, Blaine W., Ungar, Peter S. 01 December 2019 (has links)
The craniodental morphology of the early Pliocene ursid Agriotherium africanum has been studied extensively to reveal aspects of its dietary ecology. Results suggest that this large-bodied, long-legged, short-faced African native primarily consumed vertebrate matter. While many carnivoran families exhibit a clear functional relationship between craniodental form and performance on the one hand, and dietary behavior on the other, this is not always the case with Ursidae. Because of uncertainties regarding the appropriateness of using craniodental form to investigate ursid diets, questions still linger about the dietary ecology of Ag. africanum. Here, we report on a dental microwear texture analysis of six Ag. africanum lower second molars from the South African fossil site of Langebaanweg. Results support morphological evidence that suggests a diet focused on vertebrate soft tissue and bone. Unfortunately, results cannot clarify questions about mode of acquisition.
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Geology, Alteration and Mineralization of a Silicic Volcanic Center, Glass Buttes, OregonJohnson, Michael James 01 May 1984 (has links)
Glass Buttes, a Pliocene silicic volcanic complex within the High Lava Plains province of Oregon, was erupted approximately 5.0 to 5.8 million years ago. Geologic mapping revealed that the eastern portion of the complex is underlain by rhyolitic glass domes, flows and rare pyroclastis flows. Basalt flows are interlayered with and onlap the silicic glass. Younger basalt flows, erupted from local vents, overlie silicic glass and onlapping basalts.
The eastern end of Glass Buttes is hydrothermally altered at the surface; a weak geothermal anomaly coincides with the altered areas. Alteration, localized by northwest trending normal faults, occurs primarily as opalite replacement of rhyolite glass with associated cinnabar, alunite, clay-rich vein material, hematite, and hyalite. Alteration paragenesis at the surface was defined, and physicochemical conditions during hydrothermal activity were inferred from alteration minerals and assemblages and trace element content of alteration minerals.
Alteration identified in the subsurface is interpreted to be related to an older hydrothermal system. Carbonate, pyrite, quartz, and minor smectite and chlorite occur in vugs and fractures, and partially replace subsurface basalt. Abundant fine-grained disseminated pyrite occurs in permeable units. Pyrite separates from disseminations and veins within basalt and permeable glassy units contain up to 13 ppm Au. The pyrite samples are also anomalous with respect to arsenic and antimony.
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Femoral Osteohistology in American Alligators (Alligator mississippiensis) Reveals High Variation in Growth and Facilitates Interpretation of an Early Pliocene AlligatorGunnin, Davis 01 August 2023 (has links) (PDF)
Histological analysis of long bone thin sections is commonly used to infer growth rates and ecology of extinct vertebrates, particularly within Archosauria. However, most comparative neontological studies have used small samples of captive individuals, limiting the scope of variation. To fill this gap, 44 femoral thin sections of wild Alligator mississippiensis were prepared and analyzed. Comparison of slides revealed that larger individuals from cooler climates tend to show more LAGs compared to southerly A. mississippiensis of similar size, however, there is considerable variation. This pronounced variation in wild specimens emphasizes the need to use caution when interpreting paleohistological data with little modern comparative samples. Finally, thin sections of early Pliocene Alligator sp. fossils from the Gray Fossil Site (GFS), Washington Co., Tennessee were prepared. The GFS Alligator grew more slowly than A. mississippiensis examined and may have reached reproductive maturity at smaller sizes.
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