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FIGURE 1. Generalized geographic map of the southeastern United States, with counties from which Pseudaetobatus teeth were recovered (highlighted in light gray). Specific localities indicated by black dots. 1, Whynot locality, Lauderdale County, MS; 2, site AWa-1, Washington County, AL; 3, site ABu-3, Butler County, AL; 4, site ADl-1, Dale County (type locality Pseudaetobatus belli ), AL; 5, Dry Branch localities, Aiken County, SC.

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FIGURE 2. Chronostratigraphy, lithostratigraphy, and biostratigraphy of lower-to-middle Eocene strata of eastern Mississippi and Alabama. Modified from Bybell and Gibson (1985).

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FIGURE 3. Chronostratigraphy, lithostratigraphy, and biostratigraphy of middle-to-upper Eocene strata of south-central South Carolina. Abbreviation: O’burg = Orangeburg.

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FIGURE 4. Pseudaetobatus belli sp. nov. hypodigm from the type stratum within the lower Eocene (NP 13) Tallahatta Formation, Dale County, Alabama. 1, MSC 35048, lower median tooth, oblique lingual (1.1), occlusal (1.2), basal (1.3), labial (1.4), and lingual (1.5) views. 2, MSC 35054, lower right distal-most lateral tooth, occlusal (2.1), basal (2.2), distal (2.3), mesial (2.4), and labial (2.5) views. 3, MSC 35059, upper right distal-most lateral tooth, oblique lingual (3.1), occlusal (3.2), basal (3.3), and labial (3.4) views. 4, MSC 35062, intermediate lateral tooth, occlusal (4.1) (labial at top), lingual (4.2), labial (4.3), mesial (4.4), and distal (4.5) views. 5, MSC 35058, partial upper? median tooth, occlusal view. 6, Occlusal view of hypothetical reconstruction of part of the lower dentition. This consists of specimens shown in 1 (MSC 35048), 2 (MSC 35054), 4 (MSC 35062), and Figure 5.3 (MSC 35055). 2, 4, and Figure 5.3 were reduced in size to be consistent with 1. 4 was replicated and reversed to represent the left and right tooth rows. 2 and Figure 5.3 are from the right side but were reversed to represent the left side. The resulting composite series was then replicated. Scale bars equal 1.0 cm.

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FIGURE 5. Pseudaetobatus belli sp. nov. from lower Eocene strata of Alabama and Mississippi. 1, MSC 12699.1, partial upper median tooth, baso-labial (1.1), lingual oblique (1.2), occlusal (1.3), and profile (1.4) views. 2, MSC 35078, partial lower median tooth, labial (2.1), lingual (2.2), lingual oblique (2.3), occlusal (2.4), and profile (2.5) views. 3, MSC 35055, lower right distal-most lateral tooth, basal (3.1), distal (3.2), labial (3.3), mesial (3.4), and occlusal (3.5) views. 4, MSC 35081, partial median tooth, basal (4.1), labial (4.2), lingual (4.3), lingual oblique (4.4), and profile (4.5) views. 5, MSC 35049, lower median tooth, occlusal view. 6, MSC 35071, partial lower median tooth, lingual oblique (6.1), and profile (6.2) views. 7, MSC 35050, lower median tooth, occlusal view. 8, MSC 35061, upper right distal-most lateral tooth, occlusal (8.1), and basal (8.2) views. 9, MSC 12776, upper right distal-most lateral tooth, basal (9.1), labial (9.2), lingual oblique (9.3), occlusal (9.4), distal (9.5), and mesial (9.6) views. 10 , MSC 35080, partial median tooth, lingual (10.1), lingual oblique (10.2), and occlusal (10.3) views. 11, MSC 35056, lower right distal-most lateral tooth, distal (11.1), labial (11.2), lingual (11.3), mesial (11.4), and occlusal (labial at left) (11.5) views. 12, MSC 35060, upper right distal-most lateral tooth, basal (12.1), labial (12.2), lingual oblique (12.3), occlusal (12.4), mesial (12.5), and distal (12.6) views. 13, MSC 35079, partial lower median tooth, lingual oblique (13.1), and occlusal (13.2) views. 14, MSC 35065, nearly complete lower median tooth, occlusal view. 15, MSC 35052, partial lower median tooth, occlusal view. Scale bars equal 1.0 cm.

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FIGURE 6. Pseudaetobatus undulatus sp. nov. hypodigm and other specimens from the upper Eocene Dry Branch Formation, Aiken County, South Carolina. 1, SC 2013.38.91, upper right distal-most lateral tooth (holotype), basal (1.1), distal (1.2), labial (1.3), mesial (1.4), lingual oblique (1.5), and occlusal (1.6) views. 2, SC 2001.1.4.1, upper left distal-most lateral tooth, labial (2.1), lingual (2.2), and occlusal (2.3) views. 3, SC 2013.38.93.3, lower left distal-most lateral tooth, labial (3.1), lingual (3.2), and occlusal (3.3) views. 4 , SC 2001.1.5.2, intermediate lateral tooth (paratype), basal (4.1), distal (4.2), labial (4.3), mesial (4.4), lingual oblique (4.5), and occlusal (4.6) views. 5, SC 2001.1.5.1 (paratype), lower right distal-most lateral tooth, mesial (5.1), lingual oblique (5.2), distal (5.3), labial (5.4), and occlusal (5.5) views. 6, SC 2013.38.84, lower median tooth (paratype), lingual oblique (6.1), basal (6.2), and occlusal (6.3) views. 7, SC 2013.38.90, lower median tooth, lingual oblique view. 8, SC 2013.38.86, upper median tooth (paratype), (paratype), basal (8.1), baso-labial (8.2), and occlusal (8.3) views. 9, Occlusal view of hypothetical reconstruction of part of the upper dentition. This consists of specimens shown in 1 (SC 2001.1.5.2), and 8 (SC 2013.38.86. 1 and 4 were reduced in size to be consistent with 8, and they were reversed to also represent the right tooth rows. The resulting composite series was then replicated. 10, SC 2013.38.85, upper median tooth, occlusal view. Scale bars equal 0.5 cm.

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FIGURE 7. Myliobatiform ray teeth associated with Pseudaetobatus in Alabama and South Carolina, comparative specimens of Aetobatus irregularis from Alabama, and late Eocene Rhinoptera sp. from Georgia. 1, Rhinoptera sp. (Tallahatta Formation), MSC 33915, incomplete median tooth, labial (1.1), lingual (1.2), and occlusal (1.3) views. 2, Rhinoptera sp. (Dry Branch Formation), SC 2001.1.12, lateral tooth, labial (2.1), lingual (2.2), and occlusal (2.3) views. 3, Rhinoptera sp. (Clinchfield Formation), SC 2013.44.8, lateral tooth, labial (3.1), lingual (3.2), and occlusal (3.3) views. 4, Aetomylaeus sp. (Tallahatta Formation), MSC 33931, incomplete lower median tooth, labial (4.1), lingual (4.2), and occlusal (4.3) views. 5, Aetomylaeus sp. (Dry Branch Formation), SC 2001.1, incomplete lower median tooth, labial (5.1), lingual (5.2), and occlusal (5.3) views. 6, Rhinoptera sp. (Clinchfield Formation), SC 2013.44.9, distal-most lateral tooth similar to Pseudaetobatu s sp., labial (6.1), lingual (6.2), and occlusal (6.3) views. 7-8, Aetobatus irregularis (Lisbon Formation). 7, SC 2012.47.24, incomplete lower median tooth, occlusal view. 8, SC 2012.47.26, left side of upper? median tooth, distal (8.1), labial (8.2), and occlusal (8.3) views. Scale bars equal 1.0 cm.

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cicimurriDavid J. Cicimurri
South Carolina State Museum
301 Gervais Street
Columbia, South Carolina 29201
USA
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David Cicimurri is the Curator of Natural History at the South Carolina State Museum in Columbia, USA. Dave administers the State Museum’s world-renowned holdings of paleontological, geological, and modern biological specimens from the southeastern United States, with an emphasis on South Carolina. Dave also serves as a consultant for other local museums with natural history collections and is in charge of the fossil reporting for South Carolina’s hobby diver program.

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ebersoleJun A. Ebersole
McWane Science Center
200 19th Street North
Birmingham, Alabama 35203
USA
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Jun Ebersole is the Director of Collections at McWane Science Center in Birmingham, Alabama, USA. Jun oversees the Alabama Collections Center, a collection that houses nearly 500,000 specimens and objects related to the paleontology, archaeology, and geology of Alabama. Jun is both an archaeologist and paleontologist and has conducted fieldwork in various parts of the United States as well as in East Africa. Jun also serves as an Adjunct Instructor in the Department of Anthropology at the University of Alabama at Birmingham.

 
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Two new species of Pseudaetobatus Cappetta, 1986 (Batoidei: Myliobatidae) from the southeastern United States

David J. Cicimurri and Jun A. Ebersole

Plain Language Abstract

Pseudaetobatus is a genus of eagle ray that lived during the Eocene epoch between 55 and 34 million years ago. Until recently this fossil ray was only known from the African countries of Morocco and Angola. This paper describes two new species of Pseudaetobatus that have recently been found within Eocene deposits in the USA. Pseudaetobatus belli, named for paleontologist Gorden L. Bell, Jr., was found at early Eocene sites in both Alabama and Mississippi. Pseudaetobatus undulatus, named for the undulating surface of the lateral teeth of this species, was found in late Eocene sites in South Carolina. These two new species greatly expand the known geographic range of this genus and show that this genus lived nearly throughout the entire Eocene.

Resumen en Español

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Traducción: Enrique Peñalver

Résumé en Français

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Translator: Kenny J. Travouillon

Deutsche Zusammenfassung

Taxonomie, Ökologie und biogegrafische Tendenzen von domonanten benthischen Foraminiferenaten aus einem Atlantisch-Mediterranen Ästuar (Guadiana, Südost-Portugal)

Diese Studie analysiert die Taxonomie, Ökologie und Biogeografie der Arten von benthischen Foraminiferen, die an den intertidalen Rändern des Guardiana Ästuars (Südost-Portugal, Südwest-Spanien) leben. Von den 54 Taxa, die während der Sammlungskampagnen im Sommer und Winter identifiziert wurden, sind 49 systematisch gelistet und via Rasterelektronen-mikroskopie-Fotos (REM) illustriert. Ammonia spp. waren die am meist verbreiteten kalzitischen Taxa in beiden Jahreszeiten. Morphologische Analysen und REM-Aufnahmen deuteten auf drei distinkte Morphotypen der Gattung Ammonia hin, von denen zwei sich auf der Basis von partiellen RRNA-Analysen als Ammonia aberdoveyensis herausstellten. Jadammina macrescens and Miliammina fusca waren die am meisten verbreiteten agglutinierten Taxa im Ästuar. Jadammina macrescens dominiert fast alleine die oberen Marschzonen und tritt bei hoher Dichte auf. Ammonia spp. kommen am häufigsten in der niederen Marsch und der Gezeitenzone der Unterläufe des Guadiana Ästuars vor, sind aber auch weit verbreitet im gesamten Ästuar, besonders während des Sommers wenn Umweltbedingungen die Ausbreitung begünstigen. Miliammina fusca dominiert die spärlich bewachsene niedere Marsch und Gezeitenzonen der Oberläufe wo sie mit kalzitischen Arten assoziiert ist. Wegen seiner geografischen Position teilt das Guardiana-System Merkmale mit sowohl atlantischen als auch mediterranen Ästuaren. Dies spiegelt sich in den Foraminiferen-Assemblagen wieder mit einer Dominanz von thermophilen Arten und einer ökologischen Zonierung die typisch für die mediterrane Klimazone ist.

Schlüsselwörter: benthische Foraminifera; Taxonomie; Biogeographie; ökologische Zonierung; genetische Analyse; Guadiana Ästuar

Translator: Eva Gebauer

Arabic

in progress

Translator: Ashraf M.T. Elewa