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Université de Fribourg

A new testudinoid turtle from the middle to late Eocene of Vietnam

Garbin, Rafaella C. ; Böhme, Madelaine ; Joyce, Walter G.

In: PeerJ, 2019, vol. 7, p. e6280

Testudinoidea is a major clade of turtles that has colonized different ecological environments across the globe throughout the Tertiary. Aquatic testudinoids have a particularly rich fossil record in the Tertiary of the northern hemisphere, but little is known about the evolutionary history of the group, as the phylogenetic relationships of most fossils have not been established with...

Université de Fribourg

A description of the skull of eubaena cephalica (hay, 1904) and new insights into the cranial circulation and innervation of baenid turtles

Rollot, Yann ; Lyson, Tyler R. ; Joyce, Walter G.

In: Journal of Vertebrate Paleontology, 2018, vol. 38, no. 3, p. e1474886

The internal carotid system has played an important role in the systematics of fossil turtles, including baenids. A new, almost perfectly preserved specimen of Eubaena cephalica provides an opportunity to explore for the first time the cranial circulation and innervation of this taxon using CT (computed tomography) scans. We here document that the skull possesses a well-developed, branching...

Université de Fribourg

A review of the fossil record of basal mesozoic turtles

Joyce, Walter G.

In: Bulletin of the Peabody Museum of Natural History, 2017, vol. 58, no. 1, p. 65–113

Turtles (Testudinata) are the clade of amniotes characterized by a complete turtle shell. New insights into the phylogeny of the group have revealed that a diverse assemblage of fossil turtles populate the stem lineage that lead to the turtle crown (Testudines). To aid communication, the terms Mesochelydia and Perichelydia are herein defined for two internested clades more inclusive than...

Université de Fribourg

A toothed turtle from the Late Jurassic of China and the global biogeographic history of turtles

Joyce, Walter G. ; Rab, Márton ; Clark, James M. ; Xu, Xing

In: BMC Evolutionary Biology, 2016, vol. 16, p. 236

Turtles (Testudinata) are a successful lineage of vertebrates with about 350 extant species that inhabit all major oceans and landmasses with tropical to temperate climates. The rich fossil record of turtles documents the adaptation of various sub- lineages to a broad range of habitat preferences, but a synthetic biogeographic model is still lacking for the group.Results: We herein describe a...

Université de Fribourg

A new baenid turtle from the early Paleocene (Torrejonian) of New Mexico and a species-level phylogenetic analysis of Baenidae

Lyson, Tyler R. ; Joyce, Walter G. ; Lucas, Spencer G. ; Sullivan, Robert M.

In: Journal of Paleontology, 2016, vol. 90, no. 2, p. 305–316

New cranial and postcranial material of the baenid turtle Neurankylus from the Paleocene Nacimiento Formation (Torrejonian NALMA) of northwestern New Mexico represents a new species, Neurankylus torrejonensis. The material consists of a fragmented but mostly complete skull, a partial carapace and plastron, portions of both humeri, a partial pelvis, a complete right femur, and a distal phalanx....

Université de Fribourg

The Fossil Calibration Database, A New Resource for Divergence Dating

Ksepka, Daniel T. ; Parham, James. F. ; Allman, James F. ; Benton, Michael J. ; Carrano, Matthew T. ; Cranston, Karen A. ; Donoghue, Philip C. J. ; Head, Jason J. ; Hermsen, Elizabeth J. ; Irmis, Randall B. ; Joyce, Walter G. ; Kohli, Manpreet ; Lamm, Kristin S. ; Leehr, Dan ; Patané, José S. L. ; Polly, P. David ; Phillips, Matthew J. ; Smith, N. Adam ; Smith, Nathan D. ; Tuinen, Marcel van ; Ware, Jessica L. ; Warnock, Rachel C. M.

In: Systematic Biology, 2015, p. syv025

Fossils provide the principal basis for temporal calibrations, which are critical to the accuracy of divergence dating analyses. Translating fossil data into minimum and maximum bounds for calibrations is the most important, and often least appreciated, step of divergence dating. Properly justified calibrations require the synthesis of phylogenetic, paleontological, and geological evidence and...

Université de Fribourg

Evolution of neck vertebral shape and neck retraction at the transition to modern turtles: an integrated geometric morphometric approach

Werneburg, Ingmar ; Wilson, Laura A.B. ; Parr, William C. H. ; Joyce, Walter G.

In: Systematic Biology, 2014, p. syu072

The unique ability of modern turtles to retract their head and neck into the shell through a side-necked (pleurodiran) or hidden-necked (cryptodiran) motion is thought to have evolved independently in crown turtles. The anatomical changes that led to the vertebral shapes of modern turtles, however, are still poorly understood. Here we present comprehensive geometric morphometric analyses that...

Université de Fribourg

Allaeochelys libyca, a new carettochelyine turtle from the middle miocene (Langhian) of Libya

Havlik, Philipe E. ; Joyce, Walter G. ; Böhme, Madelaine

In: Bulletin of the Peabody Museum of Natural History, 2014, vol. 55, no. 2, p. 201–214

Fossil carettochelyine turtles are well known from the Paleogene of Europe (Allaeochelys), North America and Asia (Anosteira); however, the previously known Neogene fossil record is highly fragmentary and was therefore unsuitable for taxonomic analysis. In this work, we present a new carettochelyine taxon, Allaeochelys libyca, from the Middle Miocene (Langhian) of Gebel Zelten (Libya) based on an...

Université de Fribourg

A review of the fossil record of turtles of the clade Pan-Carettochelys

Joyce, Walter G.

In: Bulletin of the Peabody Museum of Natural History, 2014, vol. 55, no. 1, p. 3–33

Turtles of the total clade Pan-Carettochelys have a relatively poor fossil record that extends from the Early Cretaceous. The clade is only found in Asia during the Cretaceous, but spreads to Europe and North America during the Eocene. Neogene finds are restricted to Europe, Africa and Australia, whereas the only surviving species, Carettochelys insculpta, lives in New Guinea and the Northern...