scholarly journals An alternative interpretation of the Paleogene turtle Cardichelyon rogerwoodi as a hinged kinosternoid

2020 ◽  
Vol 94 (3) ◽  
pp. 557-567
Author(s):  
Walter G. Joyce ◽  
Julien Claude

AbstractCardichelyon rogerwoodi is an enigmatic fossil turtle from the late Paleocene to early Eocene of North America. Previous analyses suggested affiliation with Testudinoidea, in particular the big-headed turtle Platysternon megacephalum, based on the presence of multiple musk-duct foramina and a large head. We here highlight previously undocumented characteristics for this turtle, notably the presence of short costiform processes, a rib-like axillary process, and a posterior plastral hinge. Phylogenetic analysis places Cardichelyon rogerwoodi within Testudinoidea, but the exclusion of testudinoids suggest an affiliation with Dermatemydidae. Using consilience with external data we favor placement within Kinosternoidea. Cardichelyon rogerwoodi is therefore an aberrant, hinged kinosternoid that developed in situ in North America during the Paleocene long before the arrival of testudinoids on this continent in the early Eocene.

Fossil Record ◽  
2020 ◽  
Vol 23 (1) ◽  
pp. 83-93 ◽  
Author(s):  
Walter G. Joyce ◽  
Yann Rollot

Abstract. Peltochelys duchastelii is an enigmatic turtle from Early Cretaceous (middle Barremian–early Aptian) Sainte-Barbe Formation of Bernissart, Belgium. In more recent literature, there has been strong support for the trionychian affinities of this taxon, but this interpretation is less consistent with external data, in particular biogeography and temporal considerations. We provide a reinterpretation here of the lectotype of Peltochelys duchastelii that differs from more recent ones in key features. Although we agree that this turtle lacks mesoplastra, we conclude that it has 11 pairs of peripherals (not 10), likely had 12 pairs of marginals (not 11), lacks a contact between peripheral 1 and costal 1, and that a midline contact of peripherals 1 hinders the nuchal from contributing to the margin of the shell. This unusual set of characters is otherwise known from roughly coeval taxa from Europe and North America. Phylogenetic analysis yields a previously unrecognized clade of basal paracryptodiran turtles from the Late Jurassic to Paleogene of Euramerica united by a nuchal that is withdrawn from the anterior margin of the shell. The name Compsemydidae is referred to this clade. The novel hypothesis suggests that Peltochelys duchastelii did not immigrate from Asia but instead originated in Europe.


1978 ◽  
Vol 56 (9) ◽  
pp. 1136-1152 ◽  
Author(s):  
Leo J. Hickey ◽  
Rayma Kempinsky Peterson

Zingiberopsis attenuata Hickey and Peterson is a new species of monocotyledon from the Paleocene Paskapoo Formation of Alberta. Leaves of this species with their parallel veins grouped into three size sets are intermediate between the Late Cretaceous Zingiberopsis magnifolia (Knowlton) Hickey, new combination, with four discrete sets and Zingiberopsis isonervosa Hickey, of late Paleocene and early Eocene age, with only one set. Zingiberopsis has large, elliptic to ovate leaves with a costa composed of a number of concurrent strands, a set of parallel veins emerging at low angles from the costa, and relatively distantly spaced transverse veins running between adjacent parallel veins. Morphology of the genus matches that of Alpinia in the Zingiberaceae except for greater irregularity of the parallel vein set at and near their origin on the costa and the lack of any evidence of a ligule on the petiole as in Alpinia. Species of Zingiberopsis demonstrate a clear trend toward loss of the wider parallel vein subsets over the approximately 20-million-year range of the genus. In addition, the overlooked character of the arrangement of the parallel vein subsets across the width of the leaf may have potential in the taxonomic determination of monocotyledonous leaves.


2012 ◽  
Vol 183 (6) ◽  
pp. 627-633 ◽  
Author(s):  
Robert M. Sullivan ◽  
Marc Augé ◽  
Eric Wille ◽  
Richard Smith

Abstract A new glyptosaurine lizard ?Placosaurus ragei, n. sp., is recognized as being distinct from Paraplacosauriops quercyi in having a lightly built dentary, incipient heterodont teeth, lower tooth count (19), and teeth that are more gracile compared to other European glyptosaurine lizards. ?Placosaurus ragei also differs from “Placosaurus” europaeus, which has a prominent homodont dentition and is more massive. A second specimen, an isolated, nearly complete parietal, partly covered with hexagonal and polygonal osteoderms, is referable to the European glyptosaurin Placosaurus and is provisionally referred to the species ?Placosaurus ragei. A third specimen, an incomplete right frontal fragment of an indeterminate “melanosaurin,” may represent a new taxon, or may be referable to the well-known Western European taxon Placosauriops. Taxa pertaining to both tribes (Glyptosaurini and “Melanosaurini”) of glyptosaurine lizards have been recovered from the lower Eocene deposits of Dormaal, Belgium. Their apparent sudden appearance is interpreted as marking entry into western Europe. The Dormaal locality has been correlated to reference level MP7 and thus is considered to be of early Eocene age. Glyptosaurine lizards probably dispersed into western Europe, from North America, through the Greenland bridge during late Paleocene/early Eocene time.


2018 ◽  
Vol 55 (2) ◽  
pp. 75-86 ◽  
Author(s):  
Keith Berry

Icacinicaryites corruga is reported from the upper coal zone of the Raton Formation in south-central Colorado. Prior to this report, this endocarp imprint was known from only a single locality near Pagosa Springs in southwestern Colorado (Animas Formation). This demonstrates that Icacinaceae, which characterized the late Paleocene – early Eocene tropical rainforests of western North America, already were present in Colorado’s early middle Paleocene tropical rainforest. This determination agrees with the results of a reevaluation of the stratigraphic distribution of previous records of Icacinaceae from the Paleocene of western North America.


1997 ◽  
Vol 71 (5) ◽  
pp. 847-861 ◽  
Author(s):  
Richard L. Squires

Brachysphingus is a low-spired bucciniform neogastropod known only from the fossil record of California and northern Baja California. The earliest species, Brachysphingus gibbosus Nelson, 1925, ranges in age from latest Cretaceous or possibly earliest Paleocene to the late Paleocene. During the early Paleocene, the smoothish B. gibbosus evolved into the axially ribbed B. sinuatus Gabb, 1869, which is the senior primary synonym of B. gabbi Stewart, 1927. During the late Paleocene, B. sinuatus evolved into B. mammilatus Clark and Woodford, 1927, which is the youngest species of Brachysphingus and which lasted into the early Eocene.All three species of Brachysphingus were shallow-marine dwellers subject to transport into deeper waters via turbidity currents.


2018 ◽  
Vol 93 (2) ◽  
pp. 359-367 ◽  
Author(s):  
Gerald Mayr ◽  
Philip D. Gingerich ◽  
Thierry Smith

AbstractWe revisit the holotype of Calcardea junnei Gingerich, 1987 from the latest Paleocene (Clarkforkian) of the Willwood Formation (Wyoming, USA). The species is based on a partial skeleton and was originally assigned to the Ardeidae (herons). As we show, this classification cannot be upheld and Calcardea Gingerich, 1987 more closely resembles the taxon Vastanavis Mayr et al., 2007 (Vastanavidae), a parrot-like bird from the early Eocene of India. Even though C. junnei is a large bird, its long wings and short tarsometatarsus argue against a predominantly terrestrial way of living, and the morphology of the tarsometatarsus and pedal phalanges instead suggest strong grasping feet. We conclude that an assignment of Calcardea to the landbird clade (Telluraves) is better supported than its classification into the waterbird clade (Aequornithes), which includes Ardeidae and other ‘ciconiiform’ and ‘pelecaniform’ taxa. Calcardea junnei is one of the oldest known representatives of Telluraves and its morphology shows plesiomorphic features, which contributed to its previous misidentification as a heron. Calcardea exhibits a distinctive osteology and affords a glimpse of a previously unknown late Paleocene avian morphotype.


2014 ◽  
Vol 51 (10) ◽  
pp. 919-926 ◽  
Author(s):  
Brian D. Rankin ◽  
Patricia A. Holroyd

The Palaeoryctidae are a group of small-bodied, likely insectivorous mammals known principally from the Paleocene and early Eocene (from approximately 65 to 53 Ma) of North America. Here we report on a new palaeoryctid from the early Eocene (early Wasatchian (Wa3) North American Land Mammal Age) Main Body of the Wasatch Formation, Washakie Basin, near Bitter Creek station in southwestern Wyoming, USA. Acerorcytes dulcis gen. et sp. nov. is unique among palaeoryctids in having a double-rooted P2 with a small anterior cusp, P3 with pronounced para- and metastylar cusps and a reduced but conspicuous metacone, P4 with a weakly developed metacone and an anteroposteriorly compressed protocone, and M1-2 with deep ectoflexus and a sharp metastylar blade. A phylogenetic analysis based on 32 dental characters of the nine known North American palaeoryctid species, including Aceroryctes dulcis, recovered eight equally parsimonious cladograms. Similar to prior studies, the analysis suggests that the genus Palaeoryctes is non-monophyletic, with Palaeoryctes cruoris and Aaptoryctes ivyi closely related. Aceroryctes dulcis is grouped with Ottoryctes winkleri and positioned in a more inclusive clade with Eoryctes melanus; the remaining palaeoryctid taxa, including Lainoryctes youzwyshyni, are part of an unresolved polytomy. These new findings indicate that early Eocene palaeoryctids were more diverse than previously thought, with genus richness during the early Eocene at least as great as that during the middle Paleocene.


2020 ◽  
Author(s):  
Johanset Orihuela ◽  
Yasmani Ceballos Izquierdo ◽  
Roger W. Portell

ABSTRACTHerein we provide the first report of the cardiid bivalve Schedocardia from Cuba. The single, partial, valve external mold was derived from the Madruga Formation which is characterized by a richly diverse marine fauna including echinoderms, brachiopods, benthic and planktonic foraminiferans, but from which bivalves were not previously reported. The unit is considered late Paleocene in age (Thanetian), but the presence of Schedocardia supports a possible age extension of the formation into the early Eocene (Ypresian). Moreover, we provide a reconsideration of the historical factors that affected the accepted type locality of the outcrop, which allows for an alternative interpretation of the fauna found therein.RESUMENSe reporta por primera vez el género bivalvo Schedocardia de la Formación Madruga, para el registro fósil de Cuba. De esta formación se ha reportado una rica fauna de invertebrados incluyendo equinodermos, braquiópodos y, especialmente de foraminíferos, pero no moluscos bivalvos. Se ha considerado que la Formación Madruga se depositó durante el Paleoceno tardío (Thanetiano), no obstante, la presencia de Schedocardia apoya la extensión de edad de la formación hasta el Eoceno temprano (Ypresiano). Además, se consideran factores antropogénicos que han afectado la localidad tipo de la formación.


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