Sandra Chapman

Iguanodon Mantell, 1825 (Reptilia, Ornithischia): proposed designation of Iguanodon bernissartensis Boulenger in Beneden, 1881 as the type species, and proposed designation of a lectotype

The Bulletin of zoological nomenclature, 1998

Bulletin of Zoological Nomenclature 55(2) June 1998 99 Case 3037 Iguanodon Mantell, 1825 (Reptili... more

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First occurrence of the plesiochelyid turtle Plesiochelys etalloni from the Late Jurassic of England, UK

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THE SKELETAL MORPHOLOGY OF THE SOLEMYDID TURTLE NAOMICHELYS SPECIOSA FROM THE EARLY CRETACEOUS OF TEXAS

by Juliana Sterli and Sandra Chapman

The fossil record of solemydid turtles is primarily based on isolated fragments collected from La... more The fossil record of solemydid turtles is primarily based on isolated fragments collected from Late Jurassic to
Late Cretaceous sediments throughout North America and Europe and little is therefore known about the morphology and
evolutionary history of the group. We here provide a detailed description of the only known near-complete solemydid
skeleton, which was collected from the Lower Cretaceous (Aptian–Albian) Antlers Formation of Texas during the midtwentieth
century, but essentially remains undescribed to date. Though comparison is limited, the skeleton is referred to
Naomichelys speciosa, which is based on an isolated entoplastron from the Lower Cretaceous (Aptian–Albian) Kootenai
(Cloverly) Formation of Montana. The absence of temporal emarginations, contribution of the jugals to the orbits, and a
clear subdivision of the middle and inner cavities, and the presence of elongate postorbitals, posteriorly expanded
squamosals, a triangular fossa at the posterior margin of the squamosals, an additional pair of tubercula basioccipitale that
is formed by the pterygoids, foramina pro ramo nervi vidiani (VII) that are visible in ventral view, shell sculpturing
consisting of high tubercles, a large entoplastron with entoplastral scute, V-shaped anterior peripherals, and limb
osteoderms with tubercular sculpture diagnose Naomichelys speciosa as a representative of Solemydidae. The full
visibility of the parabasisphenoid complex in ventral view, the presence of an expanded symphyseal shelf, and the unusual
ventromedial folding of the coronoid process are the primary characteristics that distinguish Naomichelys speciosa from
the near-coeval European taxon Helochelydra nopcsai.

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Morphology, histology and identification of the ‘granicones’ from the Purbeck Limestone Formation (Lower Cretaceous: Berriasian) of Dorset, southern England

Cretaceous Research, Apr 1, 2002

The identification of the 'granicones', small, conical and shield-like phosphatic structures with... more The identification of the 'granicones', small, conical and shield-like phosphatic structures with a pustulate surface ornamentation, from the Purbeck Limestone Formation of Dorset, has been problematic for over 130 years. They have been interpreted as the osteoderms of theropod or ornithischian dinosaurs, lizards or crocodiles, though only circumstantial evidence was presented in support of these hypotheses. Here, we provide anatomical, histological and geological evidence that demonstrates the true affinities of the granicones: they are the limb osteoderms of turtles and may be referable to either Helochelydra (=Tretosternon) anglica or 'Tretosternon' bakewelli.

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A new basal iguanodont (Dinosauria: Ornithischia) from the Wealden (Lower Cretaceous) of England

Zenodo (CERN European Organization for Nuclear Research), Dec 31, 2010

A nearly complete right dentary originally noted by Mantell in 1848 is redescribed. The specimen,... more A nearly complete right dentary originally noted by Mantell in 1848 is redescribed. The specimen, NHMUK 28660, was discovered in a quarry near Cuckfield, West Sussex, from the same formation as the original teeth of Iguanodon anglicus. Fresh examination reveals that NHMUK 28660 exhibits a single autapomorphy (a row of foramina extending from the ventral surface of the symphysis onto the lateral surface of the dentary) and a unique combination of characters that distinguish it from all other iguanodontian dentaries. In light of this and because I. anglicus is regarded as a nomen dubium to which additional material cannot be unambiguously referred, NHMUK 28660 is made the holotype of the new genus and species Kukufeldia tilgatensis.

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Alfred Nicholson Leeds and the first fossil egg attributed to a ‘saurian’

Historical Biology, 2014

ABSTRACT

‘Old bones, dry subject’: the dinosaurs and pterosaur collected by Alfred Nicholson Leeds of Peterborough, England

Geological Society, London, Special Publications, 2010

... Corresponding author (e-mail: leslie.noe{at}thinktank.ac). Abstract. ... Note the metal crowb... more

Pride, Preparation, Principle and Prejudice: The Tenet of Hoyle and Wickramasinghe as Applied to Marine Reptiles

The death of Robert Appleby in 2004 brought to light a wealth of unpublished ichthyosaur research... more The death of Robert Appleby in 2004 brought to light a wealth of unpublished ichthyosaur research. Amongst this body of work was a description of the first ichthyosaur from Iraq, dubbed ‘Iraqisaurus kurdistanensis’. Although the manuscript was sent to Palaeontology in 1979, doubts existed regarding the Jurassic age of the specimen. Archival correspondence was consulted and a fresh sample taken from the block, confirming the pre-Aptian Early Cretaceous results previously obtained by Norman Hughes for the specimen. When publication of the work was attempted, however, these results (indicating the survival of a non-ophthalmosaurid so far beyond the J-K horizon) were regarded as somewhat heretical by one reviewer, who became increasingly hostile as the manuscript progressed. Eventually, the editor and an arbiter overruled him, as it had become obvious that his resistance was fuelled less by flaws in the evidence presented, and more by his inherent belief that such things just ‘could not be’, unfavourably reminiscent of Hoyle and Wickramasinghe’s blind belief that Archaeopteryx was a fake, simply because it did not fit their idiosyncratic views on evolutionary mechanisms. Following publication, the reviewer has repeatedly attempted to dismiss the specimen from consideration by Cretaceous researchers, through casting aspersions on the preparatory and sampling work done on the specimen. Acknowledging that academic prejudice against technical work has been a longstanding problem in palaeontology, it is hoped that more thoroughly documenting the sampling of the specimen here will lay the question of the dating of Malawania anachronus to rest once and for all.Peer reviewe

Pride, Preparation, Principle and Prejudice: The Tenet of Hoyle and Wickramasinghe as Applied to Marine Reptiles

by Jeff Liston, Darren Naish, Sandra Chapman, and Steve Brindley

Poster presented at 29th Symposium on Palaeontological Preparation and Conservation (virtual), 2020

The death of Robert Appleby in 2004 brought to light a wealth of unpublished ichthyosaur research... more The death of Robert Appleby in 2004 brought to light a wealth of unpublished ichthyosaur research. Amongst this body of work was a description of the first ichthyosaur from Iraq, dubbed ‘Iraqisaurus kurdistanensis’. Although the manuscript was sent to Palaeontology in 1979, doubts existed regarding the Jurassic age of the specimen. Archival correspondence was consulted and a fresh sample taken from the block, confirming the pre-Aptian Early Cretaceous results previously obtained by Norman Hughes for the specimen. When publication of the work was attempted, however, these results (indicating the survival of a non-ophthalmosaurid so far beyond the J-K horizon) were regarded as somewhat heretical by one reviewer, who became increasingly hostile as the manuscript progressed. Eventually, the editor and an arbiter overruled him, as it had become obvious that his resistance was fuelled less by flaws in the evidence presented, and more by his inherent belief that such things just ‘could not be’, unfavourably reminiscent of Hoyle and Wickramasinghe’s blind belief that Archaeopteryx was a fake, simply because it did not fit their idiosyncratic views on evolutionary mechanisms. Following publication, the reviewer has repeatedly attempted to dismiss the specimen from consideration by Cretaceous researchers, through casting aspersions on the preparatory and sampling work done on the specimen. Acknowledging that academic prejudice against technical work has been a longstanding problem in palaeontology, it is hoped that more thoroughly documenting the sampling of the specimen here will lay the question of the dating of Malawania anachronus to rest once and for all. (Peer reviewed)

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The earliest fossil record of a medium-sized penguin

Polish Polar Research, 2011

The earliest fossil record of a medium-sized penguinThe fossil record of Antarctic Sphenisciforme... more The earliest fossil record of a medium-sized penguinThe fossil record of Antarctic Sphenisciformes dates as early as the late Palaeocene Cross Valley Formation, Seymour Island, Antarctic Peninsula. However, the best known Antarctic locality for early penguin remains (mainly isolated bones) is the Eocene La Meseta Formation that outcrops in the northeast of Seymour Island. The analysis of an unstudied set of specimens collected there by members of the British Antarctic Survey in 1989 has resulted in identification of a distal humerus from the unit Telm3 (early Eocene) of the formation that is the oldest known bone attributable to a medium-sized (in the context of the entire Cainozoic era) penguin. This find suggests that the origin of these birds, in conjunction with an increase in taxonomic diversity of the Eocene Sphenisciformes, was related to the Early Eocene Climatic Optimum (EECO) or, more probably, the early phase of subsequent cooling.

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The skeletal morphology of the solemydid turtle Naomichelys speciosa from the Early Cretaceous of Texas

Journal of Paleontology, 2014

The fossil record of solemydid turtles is primarily based on isolated fragments collected from La... more The fossil record of solemydid turtles is primarily based on isolated fragments collected from Late Jurassic to Late Cretaceous sediments throughout North America and Europe and little is therefore known about the morphology and evolutionary history of the group. We here provide a detailed description of the only known near-complete solemydid skeleton, which was collected from the Lower Cretaceous (Aptian–Albian) Antlers Formation of Texas during the mid-twentieth century, but essentially remains undescribed to date. Though comparison is limited, the skeleton is referred to Naomichelys speciosa, which is based on an isolated entoplastron from the Lower Cretaceous (Aptian–Albian) Kootenai (Cloverly) Formation of Montana. The absence of temporal emarginations, contribution of the jugals to the orbits, and a clear subdivision of the middle and inner cavities, and the presence of elongate postorbitals, posteriorly expanded squamosals, a triangular fossa at the posterior margin of the sq...

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First report of Plesiochelys etalloni and Tropidemys langii from the Late Jurassic of the UK and the palaeobiogeography of plesiochelyid turtles

Royal Society Open Science, 2016

Plesiochelyidae is a clade of relatively large coastal marine turtles that inhabited the shallow ... more Plesiochelyidae is a clade of relatively large coastal marine turtles that inhabited the shallow epicontinental seas that covered western Europe during the Late Jurassic. Although the group has been reported from many deposits, the material is rarely identified at the species level. Here, we describe historical plesiochelyid material from the Kimmeridge Clay Formation of England and compare it with contemporaneous localities from the continent. An isolated basicranium is referred to the plesiochelyid Plesiochelys etalloni based notably on the presence of a fully ossified pila prootica. This specimen represents the largest individual known so far for this species and is characterized by remarkably robust features. It is, however, uncertain whether this represents an ontogenetic trend towards robustness in this species, some kind of specific variation (temporal, geographical or sexual), or an abnormal condition of this particular specimen. Four other specimens from the Kimmeridge Clay...

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Sandownia harrisi, a highly derived trionychoid turtle (Testudines: Cryptodira) from the Early Cretaceous of the Isle of Wight, England

Journal of Vertebrate Paleontology, 2000

Acid preparation, at the Natural History Museum, London, of a turtle skull and jaw presented to t... more Acid preparation, at the Natural History Museum, London, of a turtle skull and jaw presented to the Museum of Geology, Sandown, Isle of Wight, England, by R. W. Harris in 1931, has revealed extremely derived palatal morphology previously undescribed in turtles. The specimen is described as a new genus and species, Sandownia harrisi, and is superficially similar to certain soft-shelled turtles (family Trionychidae) although the extensive secondary palate and extensive skull roof are previously unknown for this family. Other features of the skull suggest that it is not a trionychid but can be assigned to the Trionychoidea and that its closest affinities are with the members of the Trionychia (Carettochelyidae and Trionychidae). This specimen is one of the oldest known cryptodiran turtles that nests within the living families (the Polycryptodira). It suggests that the deep divergences among the living families of the Cryptodira occurred more than 110 million years ago.

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Figure 5 In A New Basal Iguanodont (Dinosauria: Ornithischia) From The Wealden (Lower Cretaceous) Of England

FIGURE 5. Strict consensus tree of 10 MPTs of 359 steps each, following ordering of 22 multistate... more FIGURE 5. Strict consensus tree of 10 MPTs of 359 steps each, following ordering of 22 multistate characters and safe taxonomic reduction. CI = 0.532, RI = 0.842. The new taxon Kukufeldia tilgatensis is highlighted. Numbers below and to the left of some nodes correspond to the following clade names: 1, Ornithopoda; 2, Iguanodontia; 3, Rhabdodontidae; 4, Dryomorpha; 5, Dryosauridae; 6, Ankylopollexia; 7, Styracosterna; 8, Hadrosauriformes; 9, Hadrosauroidea.

Figure 4 In A New Basal Iguanodont (Dinosauria: Ornithischia) From The Wealden (Lower Cretaceous) Of England

FIGURE 4. Right dentary tooth crown of NHMUK 28660 (removed from alveolus) in lingual view. Abbre... more

Figure 2. Nhmuk 28660 In A New Basal Iguanodont (Dinosauria: Ornithischia) From The Wealden (Lower Cretaceous) Of England

FIGURE 2. NHMUK 28660, holotype right dentary of Kukufeldia tilgatensis gen. et sp. nov. in later... more FIGURE 2. NHMUK 28660, holotype right dentary of Kukufeldia tilgatensis gen. et sp. nov. in lateral (A), dorsal (B), medial (C), and rostral (D) views. Coronoid process and caudal end of the tooth row of NHMUK 28660 in medial (E) view. Abbreviations: al1, rostral-most alveolus; al18, caudal-most alveolus; dia, diastema; ist, in situ teeth; Mg, Meckelian groove; pdg, predentary groove; rcv, rough caudoventral region; srd, smooth rostrodorsal region; sym, symphysis. Scale bars in A-C and E equal 10 cm; scale bar in D equals 5 cm.

Figure 1 In A New Basal Iguanodont (Dinosauria: Ornithischia) From The Wealden (Lower Cretaceous) Of England

FIGURE 1. Dentaries of basal iguanodonts from the Wadhurst Clay Formation. Left dentary of NHMUK ... more

A new species of extinct Late Quaternary giant tortoise from Hispaniola

Zootaxa, 2017

Insular giant tortoise diversity has been depleted by Late Quaternary extinctions, but the taxono... more Insular giant tortoise diversity has been depleted by Late Quaternary extinctions, but the taxonomic status of many extinct populations remains poorly understood due to limited available fossil or subfossil material, hindering our ability to reconstruct Quaternary island biotas and environments. Giant tortoises are absent from current-day insular Caribbean ecosystems, but tortoise remains from Quaternary deposits indicate the former widespread occurrence of these animals across the northern Caribbean. We report new Quaternary giant tortoise material from several cave sites in Pedernales Province, southern Dominican Republic, Hispaniola, representing at least seven individuals, which we describe as Chelonoidis marcanoi sp. nov. Although giant tortoise material was first reported from the Quaternary record of Hispaniola almost 35 years ago, tortoises are absent from most Quaternary deposits on the island, which has been studied extensively over the past century. The surprising abundan...

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Figure 3. Nhmuk 28660 In A New Basal Iguanodont (Dinosauria: Ornithischia) From The Wealden (Lower Cretaceous) Of England

FIGURE 3. NHMUK 28660 in lateral (A) view, and rostral ramus in ventrolateral (B & C) view. In A ... more FIGURE 3. NHMUK 28660 in lateral (A) view, and rostral ramus in ventrolateral (B & C) view. In A and C, blue ellipses indicate the row of eight large foramina parallel to the tooth row, yellow indicates the row of eight smaller foramina parallel to the predentary groove (note that the rostral-most foramen is not visible in A), and red indicates the autapomorphic row of four smaller foramina that extends from the ventral surface of the symphyseal region to the lateral surface of the dentary (note that the two ventral-most foramina are not visible in A). Scale bars equal 10 cm.

Morphology, histology and identification of the ‘granicones’ from the Purbeck Limestone Formation (Lower Cretaceous: Berriasian) of Dorset, southern England

Cretaceous Research, 2002

The identification of the &amp;amp;amp;#x27;granicones&amp;amp;amp;#x27;, small, conical ... more The identification of the &amp;amp;amp;#x27;granicones&amp;amp;amp;#x27;, small, conical and shield-like phosphatic structures with a pustulate surface ornamentation, from the Purbeck Limestone Formation of Dorset, has been problematic for over 130 years. They have been interpreted as the osteoderms of theropod or ornithischian dinosaurs, lizards or crocodiles, though only circumstantial evidence was presented in support of these hypotheses. Here, we provide anatomical, histological and geological evidence that demonstrates the true affinities of the granicones ...

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