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Ren Hirayama - One of the best experts on this subject based on the ideXlab platform.

  • Puppigerus camperi (Testudines: Cryptodira: Cheloniidae) from the Ypresian (Early Eocene) of Ouled Abdoun basin, Morocco
    Bulletin de la Société Géologique de France, 2012
    Co-Authors: Haiyan Tong, Ren Hirayama, Jérôme Tabouelle
    Abstract:

    A well preserved skull of Puppigerus camperi (Testudines: Cryptodira: Cheloniidae) is reported from the Ypresian (Early Eocene) phosphate deposits of the Ouled Abdoun basin, Morocco. This discovery adds an additional element to the rich turtle assemblages hitherto known in the Ouled Abdoun basin, suggesting further close relationships with the Paleogene sea turtle fauna from northwestern Europe.

  • A new species of Argillochelys (Testudines: Cryptodira: Cheloniidae) from the Ouled Abdoun phosphate basin, Morocco
    Bulletin de la Société Géologique de France, 2008
    Co-Authors: Haiyan Tong, Ren Hirayama
    Abstract:

    EnglishA new species of Argillochelys (Testudines: Cryptodira: Cheloniidae), A. africana n. sp. is described on the basis of three skulls and a lower jaw from the Lower Tertiary beds of the Ouled Abdoun phosphate basin, Morocco. It differs from A. cuneiceps, A. antiqua and A. athersuchi essentially in the frontal well retracted from the orbital margin, with a broad prefrontal/postorbital contact, a more developed secondary palate, and the anterior part of the lower jaw more dorsoventrally flattened, with a wider triturating surface and a longer symphysis, without lingual ridge. This is the first record of Argillochelys from Africa. francaisUne nouvelle espece d'Argillochelys (Testudines, Cryptodira, Cheloniidae), A. africana n. sp., est decrite a partir de trois crânes et une mandibule provenant du Paleogene du bassin phosphate des Ouled Abdoun au Maroc. Elle differe d'A. cuneiceps, A. antiqua et A. athersuchi essentiellement par le frontal bien exclu du bord de l'orbite, un long contact prefrontal/postorbitaire, un palais secondaire plus developpe ; la partie anterieure de la mandibule plus aplatie dorsoventralement, avec une surface triturante plus large et une symphyse plus longue, sans crete linguale. C'est le premier Argillochelys decouvert en Afrique.

  • Turtle remains (Testudines, Chelonioidea) from the Middle Turonian of northwest Germany
    Netherlands Journal of Geosciences, 2003
    Co-Authors: C. Diedrich, Ren Hirayama
    Abstract:

    Turtle remains ascribed to the family Cheloniidae (Testudines, Cryptodira, Chelonioidea), collected from the lamarcki zone (Middle Turonian) at Wullen (NW Germany) are described. The material consists of a right humerus, a scapula, a complete costalia, and costalia fragments of a single individual with the humerus indicating a primitive cheloniid of the ‘toxochelyid grade’. The present material, as well as previously recorded chelonioid humeri from the Cenomanian and Turonian of Germany illustrate a progressive diversification of chelonioids during the early Late Cretaceous.

  • Osteopygis (Testudines: Cheloniidae) from the Lower Tertiary of the Ouled Abdoun phosphate basin, Morocco
    Palaeontology, 2003
    Co-Authors: Ren Hirayama, Haiyan Tong
    Abstract:

    Osteopygis emarginatus Cope 1868 is described from the Lower Tertiary of the Ouled Abdoun phosphate basin, Morocco, on the basis of skulls and lower jaws. Osteopygis is a cosmopolitan turtle that had a wide geographical distribution during the Late Cretaceous and Paleocene. Osteopygis emarginatus is a very conservative species which crossed the Cretaceous/Tertiary boundary without major changes.

  • Distribution and Diversity of Cretaceous Chelonioids
    Ancient Marine Reptiles, 1997
    Co-Authors: Ren Hirayama
    Abstract:

    Publisher Summary This chapter discusses distribution and diversity of Cretaceous chelonioids. The Cretaceous Chelonioidea, which includes at least 22 valid genera, is divided into the three monophyletic families—Cheloniidae, Protostegidae, and Dermochelyidae. The cheloniids are well diversified and abundant in the Late Cretaceous of North America and Western Europe, whereas they are absent from the Japanese Cretaceous. The Protostegidae and Dermochelyidae are considered to be more closely related to each other than either is to the cheloniids. They possess a very elongated coracoid, a pelvic girdle with a huge lateral process of the pubis, and a very long plastron. The skull of protostegids may be modified to feed on hard-shelled animals, judging from the extensive contact between pterygoid and quadrate, and the strong processus trochlearis oticum as seen in the living batagurid Malayemys, which is a typical molluscivorous freshwater turtle. The protostegids were cosmopolitan as were the dominant chelonioids from the Aptian to the Turonian; however, they drastically declined and became extinct during the Maastrichtian. The Mesozoic dermochelyids were dominant only in the Late Cretaceous of Japan. It has been suggested that most Mesozoic sea turtles are endemic, and, cosmopolitan chelonioid species are quite rare.

Max Rondon Werneck - One of the best experts on this subject based on the ideXlab platform.

Andrew D. Gentry - One of the best experts on this subject based on the ideXlab platform.

  • Prionochelys matutina Zangerl, 1953 (Testudines: Pan-Cheloniidae) from the Late Cretaceous of the United States and the evolution of epithecal ossifications in marine turtles
    PeerJ, 2018
    Co-Authors: Andrew D. Gentry
    Abstract:

    Background Many neritic to nearshore species of marine adapted turtle from the Late Cretaceous of North America are thought to represent the stem lineage of Cheloniidae but due to fragmentary holotypes, low total specimen counts, and resultantly incomplete morphological character suites, are routinely placed either within or outside of crown group Chelonioidea leaving their precise cladistic affinities uncertain. Despite this systematic ambiguity, the referral of these species to either the stem of Cheloniidae or Chelonioidea belies the critical importance of these taxa in any investigation into the origins of extant marine turtles. The adequate incorporation of these species into phylogenetic studies requires the formal description of relatively complete specimens, particularly those possessing associated cranial and post-cranial material. Methods Remarkably complete fossil specimens of several adult and juvenile marine turtles from the Mooreville Chalk and Eutaw Formations (Alabama, USA) are formally described and assigned to Prionochelys matutina. This material provides new information into the anatomy, ontogeny, and cladistic affinities of the species. A phylogenetic hypothesis for Late Cretaceous marine turtles is then generated through the consilience of stratigraphic, morphological, and molecular data. Results Phylogenetic analysis places Prionochelys matutina on the stem of Cheloniidae as a member of a monophyletic clade with other putative pan-cheloniids, including Ctenochelys stenoporus, Ctenochelys acris, Peritresius martini, and Peritresius ornatus. The members of this clade possess incipient secondary palates, pronounced carapacial and plastral fontanelles at all stages of development, and are characterized by the presence of superficial ossifications at the apices of the neural keel elevations along the dorsal midline of the carapace. Discussion The epithecal osteoderms dorsal to the neural series (epineurals) found in Ctenochelyidae are unique among turtles. The presence of epineurals in ctenochelyid turtles shows that epithecal ossifications arose independently in both leatherback (Dermochelyidae) and hard-shelled (Cheloniidae) marine turtles. Whether or not the epineurals of Ctenochelyidae are homologous with the dermal ossicles comprising the carapace of Dermochelys coriacea remains untested however, histological thin sectioning of dermochelyid and ctenochelyd epithecal elements may reveal meaningful information in future studies.

  • A new species of Peritresius Leidy, 1856 (Testudines: Pan-Cheloniidae) from the Late Cretaceous (Campanian) of Alabama, USA, and the occurrence of the genus within the Mississippi Embayment of North America
    PloS one, 2018
    Co-Authors: Andrew D. Gentry, James F. Parham, Dana J. Ehret, Jun A. Ebersole
    Abstract:

    Late Cretaceous members of Peritresius belong to a diverse clade of marine adapted turtles currently thought to be some of the earliest representatives of the lineage leading to modern hard-shelled sea turtles (Pan-Cheloniidae). Prior studies have suggested that Peritresius was monospecific, with a distribution restricted to Maastrichtian deposits in North America. However, new Peritresius specimens identified from Alabama and Mississippi, USA, show that the genus contains two taxa, Peritresius ornatus, and a new species Peritresius martini sp. nov. These two taxa are characterized by the presence of a generally cordiform carapace with moderately serrated peripherals, well-developed ventral flanges beginning at the third peripheral, squarish umbilical and lateral plastral fontanelles, and a narrow bridge formed by the contact between the hyoplastron and hypoplastron. Peritresius martini sp. nov. can be distinguished by its lack of dermal ornamentation and the presence of a ‘rib-free’ 10th peripheral. These new specimens represent the first occurrences of Peritresius from the Late Cretaceous Mississippi Embayment and extend the temporal range of this genus back to the early Campanian. When tested within a global phylogenetic context, Peritresius is placed on the stem of Cheloniidae (Pan-Cheloniidae) along with Ctenochelys and Allopleuron hofmanni. The heavily vascularized and uniquely sculptured dermal elements of P. ornatus are interpreted here as potentially relating to thermoregulation and therefore may have been one of the key factors contributing to the survival of Peritresius into the Maastrichtian, a period of cooling when other lineages of Campanian marine turtles (e.g., Protostegids, Toxochelys, and Ctenochelys) went extinct.

Reinaldo Jose Da Silva - One of the best experts on this subject based on the ideXlab platform.

  • Helminth Parasites of Juvenile Green Turtles Chelonia mydas (Testudines: Cheloniidae) in Brazil
    The Journal of parasitology, 2015
    Co-Authors: Max Rondon Werneck, Reinaldo Jose Da Silva
    Abstract:

    Abstract:  The present study offers a parasitological analysis of juvenile individuals of the green turtle (Chelonia mydas) found on the Brazilian coast between 2004 and 2011. Helminths were found in 90 out of 136 individuals (66.2%, CI = 57.7–74.0). In total, 29,411 helminths were collected, belonging to the families Brachycoeliidae, Cladorchiidae, Microscaphidiidae, Pronocephalidae, Rhytidodidae, and Spirorchiidae. Mean species richness was 4.74 (CI = 4.03–5.46), the mean intensity was 327 (CI = 223–489), and the mean abundance was 216 (CI = 146–339). This study also reports new geographical records for: Angiodictyum longum, Angiodictyum parallelum, Rameshwarotrema uterocrescens, Pyelosomum cochlear, Schizamphistomum scleroporum, Cymatocarpus solearis, and Neospirorchis sp. This is the first analysis of helminth composition in juveniles of green turtles

  • Helminth Parasites of the Juvenile Hawksbill Turtle Eretmochelys imbricata (Testudines: Cheloniidae) in Brazil
    The Journal of parasitology, 2015
    Co-Authors: Max Rondon Werneck, Eduardo H. S. M. Lima, T. T. Pires, Reinaldo Jose Da Silva
    Abstract:

    The helminth fauna of 31 juvenile specimens of Eretmochelys imbricata from the Brazilian coast was examined. Seventeen individuals were infected with helminths (54.8%). The helminths found were: Diaschistorchis pandus, Cricocephalus albus, Metacetabulum invaginatum, Pronocephalus obliquus (Pronocephalidae), Cymatocarpus solearis (Brachycoeliidae), Styphlotrema solitaria (Styphlotrematidae), Carettacola stunkardi, Amphiorchis caborojoensis (Spirorchiidae), Orchidasma amphiorchis (Telorchiidae), and Anisakis nematode larvae. This report is the first analysis of parasite communities in this host.

  • Gastrointestinal helminth parasites of Loggerhead turtle Caretta caretta Linnaeus 1758 (Testudines, Cheloniidae) in Brazil
    2008
    Co-Authors: Max Rondon Werneck, Camila Martos Thomazini, Eduardo Shigueru Mori, Verônica Thereza Gonçalves, Reinaldo Jose Da Silva
    Abstract:

    Twelve juvenile specimens of Caretta caretta were examined and results showed five of them (41.7%) were parasitized by helminthes species, as: Sulcascaris sulcata, Kathlania leptura, Orchidasma amphiorchis, Pyelosomum renicapite, and Calycodes anthos.

  • learedius learedi price 1934 digenea spirorchiidae in chelonia mydas linnaeus 1758 testudines chelonidae in brazil case report
    Arquivo Brasileiro De Medicina Veterinaria E Zootecnia, 2006
    Co-Authors: M R Werneck, J H Becker, Berenice Maria Gomes Gallo, Reinaldo Jose Da Silva
    Abstract:

    Relata-se a ocorrencia de Learedius learedi Price 1934 (Digenea, Spirorchiidae) em Chelonia mydas Linnaeus 1758 (Testudines, Chelonidae) no Brasil. Onze animais foram examinados e destes, 54,6% estavam parasitados. Duzentos e cinquenta e cinco exemplares de L. learedi foram recuperados de orgaos (coracao, figado, baco, pulmoes, rins, mesenterio) e do lavado corporal dos animais. Os resultados contribuem para o conhecimento da helmintofauna de quelonios marinhos e sua distribuicao geografica. Este e o primeiro registro da ocorrencia de L. learedi na regiao do Atlântico Sul Ocidental.

Charles D. Rice - One of the best experts on this subject based on the ideXlab platform.

  • Monoclonal antibodies against loggerhead sea turtle, Caretta caretta, IgY isoforms reveal differential contributions to antibody titers and relatedness among other sea turtles.
    Developmental and comparative immunology, 2018
    Co-Authors: Maria L. Rodgers, Charles D. Rice
    Abstract:

    Serum from loggerhead sea turtles, Caretta caretta, was collected from the southeast Atlantic Ocean during routine summer monitoring studies in 2017. Serum immunoglobulin IgY was purified and used to develop IgY isoform-specific monoclonal antibodies (mAb). mAb LH12 was developed against the 66 kDa heavy chain of IgY, mAb LH1 was developed against the truncated heavy chain of approximately 37 kDA, and mAb LH9 was developed against the 23 kDa light chains. mAb LH9 reacts with the light chains of all sea turtles, mAb LH12 reacts with the long heavy chain of all sea turtles within the family Cheloniidae, and mAb LH1 reacts with the truncated form of IgY in both olive and Kemp's ridley turtles. Circulating IgY antibodies against three different marine bacterial pathogens were determined in 16 loggerhead samples using these mAbs. mAb LH12 detects higher titers than mAb LH1, and mAb LH9 detects the highest titers.