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Daryl P. Domning - One of the best experts on this subject based on the ideXlab platform.
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Libysiren sickenbergi, gen. et sp. nov.: A New Sirenian (Mammalia, Protosirenidae) from the Middle Eocene of Libya
Journal of Vertebrate Paleontology, 2017Co-Authors: Daryl P. Domning, Geoffrey J. Heal, Silvia SorbiAbstract:ABSTRACTFossil sirenian specimens collected in 1964 by the late R. J. G. Savage's expeditions in north-central Libya are described. They come from early middle Eocene (lower Lutetian, 47.8–43.6 Ma) deposits at the locality of Bu el Haderait and represent a new genus and species, Libysiren sickenbergi. This animal is the largest known protosirenid, and the largest Eocene sirenian known to date (condylobasal length >420 mm). Its dental formula was apparently 3.1.5.3, with five premolar loci as in all other Eocene sirenians, but the teeth are mostly not preserved. Its postcranial skeleton is unknown except for the atlas, a thoracic vertebra, and rib fragments. Stable isotopes indicate a mostly seagrass diet and a habitat of fully marine salinity. The Protosirenidae presently comprise the genera Protosiren, Ashokia, and Libysiren, with their interrelationships unresolved. Together, they are most parsimoniously regarded as a paraphyletic group basal to both Trichechidae and Dugongidae. However, as more of thei...
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Morphological and systematic re-assessment of the late Oligocene “Halitherium” bellunense reveals a new crown group genus of Sirenia
Acta Palaeontologica Polonica, 2017Co-Authors: Manja Voss, Silvia Sorbi, Daryl P. DomningAbstract:“Halitherium” bellunense is exclusively known from a single individual from upper Oligocene glauconitic sandstone near Belluno, northern Italy. According to a review of its morphological basis, which consists of associated cranial elements, some vertebrae and ribs, this specimen is identified as a juvenile, because the first upper incisor (I1) and supposedly second upper molar (M2) are not fully erupted. However, its juvenile status allowed only cautious conclusions on its taxonomy and systematic affinity. The presence of a nasal process of the premaxilla with a broadened and bulbous posterior end, and a lens-shaped I1, corroborate an evolutionarily-derived status of this species that places it well within the sirenian crown group Dugonginae. Considering these new data and in order to avoid continued misuse of the inappropriate generic name of Halitherium, a new generic name, Italosiren gen. nov., and emended species diagnosis are supplied for this taxon
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SIRENIA FOSSILS FROM QOM FORMATION (BURDIGALIAN) OF THE KABUDAR AHANG AREA, NORTHWEST IRAN
Rivista Italiana Di Paleontologia E Stratigrafia, 2016Co-Authors: Nasrollah Abbassi, Daryl P. Domning, Navid Navidi Izad, Safoora ShakeriAbstract:Fossil remains of sirenians (Mammalia; Dugongidae) are reported from the late early Miocene (Burdigalian) Qom Formation near the town of Shirin Su, northwest Kabudar Ahang region, west of Tehran, Iran. The fossils consist of partial postcranial skeletons preserved mostly as natural molds in limestone. In the absence of skulls or other diagnostic elements, it is not evident which dugongid subfamily these specimens represent: Halitheriinae or Dugonginae. Both subfamilies were present in contemporaneous Western Tethys (Mediterranean) deposits, but so far only dugongines have been found in Neogene rocks of Eastern Tethys. Since the Iranian deposits are located between these two parts of the former Tethys Seaway, it will be interesting to see which group(s) the Iranian sirenians prove to represent, once their taxonomic identity has been determined through future discoveries.
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Order Proboscidea
2015Co-Authors: Caryn Self-sullivan, Daryl P. Domning, Jorge Vélez-juarbeAbstract:The order Sirenia is closely associated with a large group of hoofed mammals known as Tethytheria, which includes the extinct orders Desmostylia (hippopotamus-like marine mammals) and Embrithopoda (rhinoceros-like mammals). Sirenians probably split off from these relatives in the Palaeocene (65-54 mya) and quickly took to the water, dispersing to the New World. This outline attempts to order all the species described from the fossil record in chronological order within each of the recognized families of Prorastomidae, Protosirenidae, Dugongidae, and Trichechidae. This outline began as an exercise in preparation for my Ph. D. preliminary exams and is primarily based on decades of research and peer-reviewed literature by Dr. Daryl P. Domning, to whom I am eternally grateful. It has been recently updated with the help of Dr. Jorge Velez-Juarbe. However, this document continues to be a work-in-progress and not a peer reviewed publication
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fossil sirenia of the west atlantic and caribbean region xi callistosiren boriquensis gen et sp nov
Journal of Vertebrate Paleontology, 2015Co-Authors: Jorge Velezjuarbe, Daryl P. DomningAbstract:ABSTRACTHere we describe a new taxon of late Oligocene dugongine from the Western Atlantic and Caribbean region. Known from cranial and postcranial material, Callistosiren boriquensis, gen. et sp. nov., differs from other members of the group by displaying the following unique combination of characters: nasal process of premaxilla tapering but thickened; supraorbital process of frontal dorsoventrally thin (<2 cm) and well developed with recurved, bluntly pointed posterolateral corner; ventral rim of orbit not overhanging the lateral surface of the jugal; pterygoid fossa tall; tusks large, lozenge- or kite-shaped in cross-section, and with enamel confined to the medial side; lacrimals with thin, elongated dorsal process that is wedged between the premaxilla and frontal; and osteosclerotic but minimally pachyostotic ribs and vertebrae. A phylogenetic analysis places Callistosiren as one of the more basal members of the Dugonginae, but we note that the relationships and taxonomy of more derived members are i...
Jorge Velezjuarbe - One of the best experts on this subject based on the ideXlab platform.
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an early miocene dugongine sirenia Dugongidae from panama
Journal of Vertebrate Paleontology, 2018Co-Authors: Jorge Velezjuarbe, Aaron R. WoodAbstract:Herein, we describe a new early Miocene dugongine from marine deposits of the Culebra Cut (Gaillard Cut) of the Panama Canal. The new taxon, Culebratherium alemani, gen. et sp. nov., represents one...
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fossil sirenia of the west atlantic and caribbean region xi callistosiren boriquensis gen et sp nov
Journal of Vertebrate Paleontology, 2015Co-Authors: Jorge Velezjuarbe, Daryl P. DomningAbstract:ABSTRACTHere we describe a new taxon of late Oligocene dugongine from the Western Atlantic and Caribbean region. Known from cranial and postcranial material, Callistosiren boriquensis, gen. et sp. nov., differs from other members of the group by displaying the following unique combination of characters: nasal process of premaxilla tapering but thickened; supraorbital process of frontal dorsoventrally thin (<2 cm) and well developed with recurved, bluntly pointed posterolateral corner; ventral rim of orbit not overhanging the lateral surface of the jugal; pterygoid fossa tall; tusks large, lozenge- or kite-shaped in cross-section, and with enamel confined to the medial side; lacrimals with thin, elongated dorsal process that is wedged between the premaxilla and frontal; and osteosclerotic but minimally pachyostotic ribs and vertebrae. A phylogenetic analysis places Callistosiren as one of the more basal members of the Dugonginae, but we note that the relationships and taxonomy of more derived members are i...
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iterative evolution of sympatric seacow Dugongidae sirenia assemblages during the past 26 million years
PLOS ONE, 2012Co-Authors: Daryl P. Domning, Nicholas D. Pyenson, Jorge VelezjuarbeAbstract:Extant sirenians show allopatric distributions throughout most of their range. However, their fossil record shows evidence of multispecies communities throughout most of the past ∼26 million years, in different oceanic basins. Morphological differences among co-occurring sirenian taxa suggest that resource partitioning played a role in structuring these communities. We examined body size and ecomorphological differences (e.g., rostral deflection and tusk morphology) among sirenian assemblages from the late Oligocene of Florida, early Miocene of India and early Pliocene of Mexico; each with three species of the family Dugongidae. Although overlapping in several ecomorphological traits, each assemblage showed at least one dominant trait in which coexisting species differed. Fossil sirenian occurrences occasionally are monotypic, but the assemblages analyzed herein show iterative evolution of multispecies communities, a phenomenon unparalleled in extant sirenian ecology. As primary consumers of seagrasses, these communities likely had a strong impact on past seagrass ecology and diversity, although the sparse fossil record of seagrasses limits direct comparisons. Nonetheless, our results provide robust support for previous suggestions that some sirenians in these extinct assemblages served as keystone species, controlling the dominance of climax seagrass species, permitting more taxonomically diverse seagrass beds (and sirenian communities) than many of those observed today.
Nicholas D. Pyenson - One of the best experts on this subject based on the ideXlab platform.
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Iterative Evolution of Sympatric Seacow (Dugongidae, Sirenia) Assemblages during the Past ~26 Million Years
PloS one, 2012Co-Authors: Jorge Vélez-juarbe, Daryl P. Domning, Nicholas D. PyensonAbstract:Extant sirenians show allopatric distributions throughout most of their range. However, their fossil record shows evidence of multispecies communities throughout most of the past ∼26 million years, in different oceanic basins. Morphological differences among co-occurring sirenian taxa suggest that resource partitioning played a role in structuring these communities. We examined body size and ecomorphological differences (e.g., rostral deflection and tusk morphology) among sirenian assemblages from the late Oligocene of Florida, early Miocene of India and early Pliocene of Mexico; each with three species of the family Dugongidae. Although overlapping in several ecomorphological traits, each assemblage showed at least one dominant trait in which coexisting species differed. Fossil sirenian occurrences occasionally are monotypic, but the assemblages analyzed herein show iterative evolution of multispecies communities, a phenomenon unparalleled in extant sirenian ecology. As primary consumers of seagrasses, these communities likely had a strong impact on past seagrass ecology and diversity, although the sparse fossil record of seagrasses limits direct comparisons. Nonetheless, our results provide robust support for previous suggestions that some sirenians in these extinct assemblages served as keystone species, controlling the dominance of climax seagrass species, permitting more taxonomically diverse seagrass beds (and sirenian communities) than many of those observed today.
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iterative evolution of sympatric seacow Dugongidae sirenia assemblages during the past 26 million years
PLOS ONE, 2012Co-Authors: Daryl P. Domning, Nicholas D. Pyenson, Jorge VelezjuarbeAbstract:Extant sirenians show allopatric distributions throughout most of their range. However, their fossil record shows evidence of multispecies communities throughout most of the past ∼26 million years, in different oceanic basins. Morphological differences among co-occurring sirenian taxa suggest that resource partitioning played a role in structuring these communities. We examined body size and ecomorphological differences (e.g., rostral deflection and tusk morphology) among sirenian assemblages from the late Oligocene of Florida, early Miocene of India and early Pliocene of Mexico; each with three species of the family Dugongidae. Although overlapping in several ecomorphological traits, each assemblage showed at least one dominant trait in which coexisting species differed. Fossil sirenian occurrences occasionally are monotypic, but the assemblages analyzed herein show iterative evolution of multispecies communities, a phenomenon unparalleled in extant sirenian ecology. As primary consumers of seagrasses, these communities likely had a strong impact on past seagrass ecology and diversity, although the sparse fossil record of seagrasses limits direct comparisons. Nonetheless, our results provide robust support for previous suggestions that some sirenians in these extinct assemblages served as keystone species, controlling the dominance of climax seagrass species, permitting more taxonomically diverse seagrass beds (and sirenian communities) than many of those observed today.
Silvia Sorbi - One of the best experts on this subject based on the ideXlab platform.
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Libysiren sickenbergi, gen. et sp. nov.: A New Sirenian (Mammalia, Protosirenidae) from the Middle Eocene of Libya
Journal of Vertebrate Paleontology, 2017Co-Authors: Daryl P. Domning, Geoffrey J. Heal, Silvia SorbiAbstract:ABSTRACTFossil sirenian specimens collected in 1964 by the late R. J. G. Savage's expeditions in north-central Libya are described. They come from early middle Eocene (lower Lutetian, 47.8–43.6 Ma) deposits at the locality of Bu el Haderait and represent a new genus and species, Libysiren sickenbergi. This animal is the largest known protosirenid, and the largest Eocene sirenian known to date (condylobasal length >420 mm). Its dental formula was apparently 3.1.5.3, with five premolar loci as in all other Eocene sirenians, but the teeth are mostly not preserved. Its postcranial skeleton is unknown except for the atlas, a thoracic vertebra, and rib fragments. Stable isotopes indicate a mostly seagrass diet and a habitat of fully marine salinity. The Protosirenidae presently comprise the genera Protosiren, Ashokia, and Libysiren, with their interrelationships unresolved. Together, they are most parsimoniously regarded as a paraphyletic group basal to both Trichechidae and Dugongidae. However, as more of thei...
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Morphological and systematic re-assessment of the late Oligocene “Halitherium” bellunense reveals a new crown group genus of Sirenia
Acta Palaeontologica Polonica, 2017Co-Authors: Manja Voss, Silvia Sorbi, Daryl P. DomningAbstract:“Halitherium” bellunense is exclusively known from a single individual from upper Oligocene glauconitic sandstone near Belluno, northern Italy. According to a review of its morphological basis, which consists of associated cranial elements, some vertebrae and ribs, this specimen is identified as a juvenile, because the first upper incisor (I1) and supposedly second upper molar (M2) are not fully erupted. However, its juvenile status allowed only cautious conclusions on its taxonomy and systematic affinity. The presence of a nasal process of the premaxilla with a broadened and bulbous posterior end, and a lens-shaped I1, corroborate an evolutionarily-derived status of this species that places it well within the sirenian crown group Dugonginae. Considering these new data and in order to avoid continued misuse of the inappropriate generic name of Halitherium, a new generic name, Italosiren gen. nov., and emended species diagnosis are supplied for this taxon
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Metaxytherium subapenninum (Bruno, 1839) (Mammalia, Dugongidae), the Latest Sirenian of the Mediterranean Basin
Journal of Vertebrate Paleontology, 2012Co-Authors: Silvia Sorbi, Daryl P. Domning, Stefano Claudio Vaiani, Giovanni BianucciAbstract:ABSTRACT Metaxytherium subapenninum was a halitheriine dugongid distributed along the northwestern coasts of the Mediterranean Basin during the early and late Pliocene. It represents the latest sirenian species of the Mediterranean Basin, the latest Metaxytherium species in the world, and also the latest species belonging to the paraphyletic subfamily Halitheriinae. We review M. subapenninum in the light of new discoveries, including its stratigraphic and geographic distribution, osteology, paleoecology, and relationships. M. subapenninum represents a more derived stage of evolution in comparison with the earlier Metaxytherium species. It is characterized in particular by an increase in body size, an increase in tusk size, and a dorsal broadening of the nasal process of the premaxilla. Its variation in tusk size does not appear to represent sexual dimorphism as in the modern Dugong, but instead progressive intraspecific evolution of larger tusks as a feeding adaptation convergent on that of derived dugong...
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rytiodus heali sp nov a new sirenian mammalia dugonginae from the miocene of libya
Journal of Vertebrate Paleontology, 2011Co-Authors: Daryl P. Domning, Silvia SorbiAbstract:ABSTRACT A species of the dugongine dugongid genus Rytiodus from the Miocene (Burdigalian—Langhian; 19–14 Ma) deposits of Jabal Zaltan (= Gebel Zelten), Libya, is re-described, considered a valid species differing from Rytiodus capgrandi from the lower Miocene (Aquitanian) of the Aquitaine Basin (SW France), and named Rytiodus heali. R. heali, together with R. capgrandi and Corystosiren varguezi appear to constitute a taxon of dugongines characterized by broad, mediolaterally compressed, blade-like tusks with enamel mainly on the medial side, and a modified nasal process of the premaxilla. They are regarded as specialized seagrass feeders, using their tusks in excavation of seagrass rhizomes. Rytiodus lived sympatrically with the generalist small-tusked halitheriine dugongid genus Metaxytherium.
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the southernmost sirenian record in the eastern pacific ocean from the late miocene of chile
Comptes Rendus Palevol, 2006Co-Authors: Giovanni Bianucci, Silvia Sorbi, Mario E Suarez, Walter LandiniAbstract:A tooth of a sirenian from the Late Miocene sediments of the Bahia Inglesa Formation (Chile) is described and referred to the Dugongidae. The fossil represents the first sirenian record from Chile and the southernmost record of the Sirenia in the eastern Pacific Ocean (latitude 27° S). The Chilean record extends the already wide geographical distribution of fossil sirenians along the Eastern Pacific coast. The presence of a sirenian during the Miocene on the Chilean coast is related to a globally warmer climatic condition and a still limited northern extension of the cold Humboldt Current. To cite this article: G. Bianucci, C. R. Palevol 5 (2006).
Jorge Vélez-juarbe - One of the best experts on this subject based on the ideXlab platform.
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An early Miocene dugongine (Sirenia: Dugongidae) from Panama
2019Co-Authors: Jorge Vélez-juarbe, Aaron R. WoodAbstract:Herein, we describe a new early Miocene dugongine from marine deposits of the Culebra Cut (Gaillard Cut) of the Panama Canal. The new taxon, Culebratherium alemani, gen. et sp. nov., represents one of the few records of late Aquitanian–early Burdigalian sirenians and the oldest sirenian from Central America. A phylogenetic analysis places Culebratherium in a clade with Dioplotherium cf. D. allisoni (Miocene of Brazil), Dioplotherium allisoni (Miocene of Baja California Sur, Mexico, and California, U.S.A.), and Dioplotherium sp. (Pliocene of Yucatan, Mexico). Similar to these taxa, Culebratherium is characterized by the presence of large incisor tusks, a premaxillary symphysis without a boss, a premaxilla-frontal suture forming a butt joint, and a moderately downturned rostrum. In addition, Culebratherium exhibits prominent occipital-cervical attachment sites for enlarged neck musculature. These features taken together are interpreted as adaptations for uprooting large, deeply buried seagrass rhizomes. Other dugongines with similar, yet convergent, dental and facial adaptations are known from earlier or coeval deposits in Puerto Rico, Florida, South Carolina, California, Baja California Sur, Brazil, and India and were constituents of sympatric paleocommunities of sirenians. Only fragmentary evidence of a second smaller and unidentifiable sirenian species is known from the Culebra Formation, but future discoveries may reveal a similar sympatric paleocommunity during the early Miocene of Panama. Finally, we used the results of the phylogenetic analysis to propose the new clade Pan-Sirenia as the most inclusive group consisting of stem and crown groups and redefine the Sirenia, Dugongidae, and Dugonginae clades.
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Order Proboscidea
2015Co-Authors: Caryn Self-sullivan, Daryl P. Domning, Jorge Vélez-juarbeAbstract:The order Sirenia is closely associated with a large group of hoofed mammals known as Tethytheria, which includes the extinct orders Desmostylia (hippopotamus-like marine mammals) and Embrithopoda (rhinoceros-like mammals). Sirenians probably split off from these relatives in the Palaeocene (65-54 mya) and quickly took to the water, dispersing to the New World. This outline attempts to order all the species described from the fossil record in chronological order within each of the recognized families of Prorastomidae, Protosirenidae, Dugongidae, and Trichechidae. This outline began as an exercise in preparation for my Ph. D. preliminary exams and is primarily based on decades of research and peer-reviewed literature by Dr. Daryl P. Domning, to whom I am eternally grateful. It has been recently updated with the help of Dr. Jorge Velez-Juarbe. However, this document continues to be a work-in-progress and not a peer reviewed publication
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Iterative Evolution of Sympatric Seacow (Dugongidae, Sirenia) Assemblages during the Past ~26 Million Years
PloS one, 2012Co-Authors: Jorge Vélez-juarbe, Daryl P. Domning, Nicholas D. PyensonAbstract:Extant sirenians show allopatric distributions throughout most of their range. However, their fossil record shows evidence of multispecies communities throughout most of the past ∼26 million years, in different oceanic basins. Morphological differences among co-occurring sirenian taxa suggest that resource partitioning played a role in structuring these communities. We examined body size and ecomorphological differences (e.g., rostral deflection and tusk morphology) among sirenian assemblages from the late Oligocene of Florida, early Miocene of India and early Pliocene of Mexico; each with three species of the family Dugongidae. Although overlapping in several ecomorphological traits, each assemblage showed at least one dominant trait in which coexisting species differed. Fossil sirenian occurrences occasionally are monotypic, but the assemblages analyzed herein show iterative evolution of multispecies communities, a phenomenon unparalleled in extant sirenian ecology. As primary consumers of seagrasses, these communities likely had a strong impact on past seagrass ecology and diversity, although the sparse fossil record of seagrasses limits direct comparisons. Nonetheless, our results provide robust support for previous suggestions that some sirenians in these extinct assemblages served as keystone species, controlling the dominance of climax seagrass species, permitting more taxonomically diverse seagrass beds (and sirenian communities) than many of those observed today.
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FOSSIL Dugongidae (MAMMALIA, SIRENIA) FROM THE PARANÁ FORMATION (LATE MIOCENE) OF ENTRE RÍOS PROVINCE, ARGENTINA
Ameghiniana, 2012Co-Authors: Jorge Vélez-juarbe, Jorge Ignacio Noriega, Brenda Soledad FerreroAbstract:Abstract. Fossil sirenians are well known from the Western Atlantic and Caribbean (WAC) region. Neogene records from the Atlantic coast of South America, although scarce, seem to reflect a similar taxonomic composition to its northern contemporaries. Fossil sirenians from Argentina are known from the late Miocene Parana and Ituzaingo formations in Entre Rios Province. An upper third molar housed in the Museo de Paleontologia de la Universidad Nacional de Cordoba (CORD-PZ 4301), from the Parana Formation, was originally described and assigned to the dugongid genus Metaxytherium Christol. Subsequent workers suggested it could instead belong to the dugongid genus Dioplotherium Cope, a designation that we confirm upon examination of the material. Additionally, we describe new sirenian remains from the Parana Formation, consisting of two incomplete maxillae with teeth, belonging to one individual, deposited at the Museo de Ciencias Naturales de Parana (MASP 373). This specimen shows similarities with species o...
