Browsing by Author "Gaffney, Eugene S."
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Item Acleistochelys, a new side-necked turtle (Pelomedusoides, Bothremydidae) from the Paleocene of Mali ; American Museum novitates, no. 3549(New York, NY : American Museum of Natural History, 2007) Gaffney, Eugene S.; Roberts, Eric (Eric M.); Sissoko, Famory.; Bouaré, Mohamed L.; Tapanila, Leif Michael.; O'Leary, Maureen A.The Paleocene Teberemt Formation south of the Adrar des Iforas Mountains, between Saguirilidad and In Fargas, Mali, yielded a nearly complete skull of a new genus and species of side-necked turtle, Acleistochelys maliensis. Acleistochelys is a member of the family Bothremydidae Baur, 1891, because: (1) the fossa precolumellaris is absent, (2) the foramen stapedio-temporale faces anteriorly, (3) the eustachian tube is separated from the stapes by bone, and (4) an exoccipital-quadrate contact is present. Within the Bothremydidae, Acleistochelys belongs to the tribe Taphrosphyini because: (1) the maxilla-quadratojugal contact is absent, (2) the palate is dorsally arched, (3) there is only a small contribution of the palatine to the triturating surfaces, and (4) the septum orbitotemporale is at least partially open. Acleistochelys is most closely related to Azabbaremys because both share a narrow vomer lacking a posterior attachment to the palatines. The specimen was found in a marine limestone associated with crocodiles, echinoids, and mollusks.Item Azabbaremys, a new side-necked turtle (Pelomedusoides, Bothremydidae) from the Paleocene of Mali. American Museum novitates ; no. 3320(New York, NY : American Museum of Natural History, 2001) Gaffney, Eugene S.; Moody, Richard, 1939-; Walker, Cyril Alexander.The Paleocene Teberemt Formation in eastern Mali has yielded the skull of a new genus of side-necked turtle, Azabbaremys moragjonesi, new genus and species. Azabbaremys is a pelomedusoid pleurodire belonging to the family Bothremydidae Baur, 1891, based on these characters: (1) precolumellar fossa absent, (2) occipital condyle consisting only of exoccipitals, (3) foramen stapedio-temporale not visible in dorsal view and very close to foramen nervi trigemini, (4) eustachian tube and stapes separated by bone, (5) incisura columellae auris closed, and (6) exoccipital contacts quadrate. Within the Bothremydidae, Azabbaremys is best resolved as a member of the group containing Taphrosphys, Nigeremys, and Arenila because it has a dorsally arched palate and an open postorbital wall.Item Bairdemys, a new side-necked turtle (Pelomedusoides, Podocnemididae) from the Miocene of the Caribbean. American Museum novitates ; no. 3359(New York, NY : American Museum of Natural History, 2002) Gaffney, Eugene S.; Wood, Roger Conant.A new genus, Bairdemys, is erected for two species of side-necked turtles. Bairdemys venezuelensis (Wood and Díaz de Gamero, 1971) from the late Miocene Urumaco Formation of Venezuela is represented by four skulls and a number of shells. Bairdemys hartsteini from the Miocene of Puerto Rico is known from a skull. Bairdemys is a member of the Podocnemididae because it possesses a cavum pterygoideus, and is related to the Shweboemys Group because it has a well-developed secondary palate. It differs from all other Podocnemididae in having large ventral convexities on the secondary palate, the eustachian tube separated by bone from the fenestra postotica, and the frontal and prefrontal strongly convex dorsally.Item Caninemys, a new side-necked turtle (Pelomedusoides, Podocnemididae) from the Miocene of Brazil. (American Museum novitates, no. 3639)(2009) Meylan, Peter A. (Peter Andre); Gaffney, Eugene S.; Campos, Diógenes de Almeida.A new genus and species of podocnemidid pleurodire, Caninemys tridentata, is described on the basis of a skull collected by L.I. Price in 1962 from the late Miocene of Acre, Brazil. It is unique among podocnemidids (and all other turtles) in having greatly inflated maxillae, each with a ventral, toothlike process. Along with a midline process of the premaxillae, these processes form a tridentate condition in the upper triturating surface, also unique among podocnemidids but comparable to the condition in the kinosternid Claudius. This skull has previously been identified as the shell-based genus Stupendemys, but there are no associations supporting this assignment. The type specimens are separated by over 2000 km, and other large podocnemidid taxa are known from this time and region. Although relatively large with a condylobasal skull length of about 17 cm, Caninemys was probably about half the size of Stupendemys. Phylogenetic analysis of 63 skeletal characters provides evidence that this new taxon nests within the family Podocnemididae as follows: (Bauruemys (“Roxochelys” (Podocnemis (Caninemys (Dacquemys ((Erymnochelys, Peltocephalus) (Neochelys (Shweboemys, Stereogenys)))))))).Item Cearachelys, a new side-necked turtle (Pelomedusoides, Bothremydidae) from the early Cretaceous of Brazil. American Museum novitates ; no. 3319(New York, NY : American Museum of Natural History, 2001) Gaffney, Eugene S.; Campos, Diógenes de Almeida.; Hirayama, Ren.The early Cretaceous Santana Formation exposed on the Chapada do Araripe in Ceará State, northeastern Brazil, has yielded remains of a side-necked turtle, Cearachelys placidoi, new genus and species. Cearachelys is based on two skeletons, each consisting of articulated shell, associated skull, and postcrania in varying degrees of completeness. Cearachelys is a pelomedusoid pleurodire belonging to the family Bothremydidae Baur, 1891, based on these bothremydid characters: (1) precolumellar fossa absent, (2) occipital condyle consisting only of exoccipitals, (3) foramen stapedio-temporale anteriorly facing, and (4) exoccipital contacts quadrate. Within the Bothremydidae, Cearachelys is best resolved as the sister group of Bothremys, Rosasia, Foxemys, Zolhafah, and Polysternon. Cearachelys differs from the other two pleurodires in the Santana Formation in the bothremydid characters listed above and in having a quadrate-basioccipital contact, a prootic completely covered in ventral view, and a high lingual ridge on the lower jaw.Item The cervical and caudal vertebrae of the cryptodiran turtle, Meiolania platyceps, from the Pleistocene of Lord Howe Island, Australia. American Museum novitates ; no. 2805(New York, N.Y. : American Museum of Natural History, 1985) Gaffney, Eugene S."Meiolania platyceps, a cryptodiran turtle from the Pleistocene of Lord Howe Island, Australia, has cervical and caudal vertebrae exhibiting a number of phylogenetically interesting features. The cervicals have fully formed central articulations with a formula of (2( (3( (4) )5) )6) )7) )8), interpreted as a synapomorphy of eucryptodires. Free ribs are present on cervicals two through six, a retained primitive character in Meiolania, lost independently in other eucryptodires, baenids, and Pleurodires. The presence in Meiolania of cervical ribs articulating with paired intercentra shows that the supposed vestigial ribs identified by previous authors in the neck of Recent turtles are probably intercentra and not rib remnants. The neural spines of cervicals seven and eight articulate with the nuchal bone; this is interpreted as an autapomorphy, occurring independently in chelonioids. Complete tails are unknown for Meiolania platyceps, but a conservative reconstruction based on degree of serial variation and comparison with Recent turtles, yields a total of at least ten caudals plus tail club. The caudals are all opisthocoelus and have well-developed haemal spines; characters that are primitive for cryptodires. Meiolania has an ossified tail club consisting of a conical layer of bone surrounding and fused to the terminal caudals. Proganochelys has a similar, but not identical, terminal ossification, and the presence of a tail club is interpreted as a retained primitive feature in Meiolania, being lost independently in pleurodires and other cryptodires. The tail of Meiolania platyceps has a series of ventrally incomplete rings, contrasting with the complete rings found in 'Meiolania' oweni and Niolamia argentina. The vertebral features of Meiolania platyceps are consistent with its hypothesized systematic position as a primitive eucryptodire"--P. [1].Item Chelid turtles from the Miocene freshwater limestones of Riversleigh Station, northwestern Queensland, Australia. American Museum novitates ; ; no. 2959.(New York, N.Y. : American Museum of Natural History, 1989) Gaffney, Eugene S.; Archer, Michael, 1945-; White, Arthur, paleontologist.Item Chubutemys, a new eucryptodiran turtle from the early Cretaceous of Argentina, and the relationships of the Meiolaniidae ; American Museum novitates, no. 3599(New York, NY : American Museum of Natural History, 2007) Gaffney, Eugene S.; Rich, Thomas H. V.; Rich, Pat Vickers.; Constantine, Andrew Eric, 1965-; Vacca, Raul.; Kool, Lesley.Chubutemys copelloi is the oldest nonmarine cryptodire from South America represented by a skull. The skull and associated postcranial fragments are from the Aptian Cerro CostaŠno Member of the Cerro Barcino Formation of Chubut, Argentina. Chubutemys has a processus trochlearis oticum, showing that it is a cryptodire, and an enclosed canalis caroticus internus extending to the posterior margin of the pterygoid, showing that it is a eucryptodire. The skull of Chubutemys is similar to that of other primitive eucryptodires, particularly Dracochelys, but also to Hangaiemys, Judithemys, Sinemys, and Ordosemys. Chubutemys differs from all these, however, in possessing a solidly roofed skull, formed by long, wide parietals, rather than a posterior emargination. Chubutemys also differs from these taxa in having no cheek emargination. A phylogenetic analysis using PAUP* analyzed 104 parsimony-informative characters resolving into one most parsimonious cladogram of 224 steps, a consistency index of 0.55, and a retention index of 0.74. The phylogenetic analysis weakly joins Chubutemys and meiolaniids on the basis of the prefrontal-postorbital contact. Chubutemys also has a fully roofed skull and slitlike posterior opening of the foramen caroticum laterale (foramen posterius canalis caroticus laterale), features to be expected in a meiolaniid sister taxon. Chubutemys provides further evidence that meiolaniids are related to 'basal' eucryptodires ('sinemydids/macrobaenids'), that is, eucryptodires outside the living Cryptodira, the Polycryptodira. The basicranial morphology of meiolaniids, with an intrapterygoid slit, rather than being a unique feature of the group is instead a modified state of the primitive eucryptodire condition, as seen in such forms as Chubutemys, Dracochelys, Ordosemys, and Sinemys. The intrapterygoid slit of meiolaniids is homologous with the pterygoid flange associated with the foramen caroticum laterale (foramen posterius canalis caroticus laterale of Sukhanov) in non-Polycryptodiran eucryptodires like Ordosemys. Chubutemys shows that nonmarine eucryptodires were present in South America in the Cretaceous, as they were in North America, central Asia, and Australia.Item Comparative cranial morphology of Recent and fossil turtles. Bulletin of the AMNH ; v. 164, article 2(New York : American Museum of Natural History, 1979) Gaffney, Eugene S."Comparative descriptions of the cranial morphology in living and extinct turtles are presented in this paper. Descriptions are arranged by bone rather than by taxon and attempt to document the types and degrees of differences in cranial structures within the Testudines, emphasizing features of systematic interest. Developmental information is also included. 273 figures supplement the text. About half of these figures show detailed internal morphology and include comparative series showing horizontal and sagittal sections, and oblique views of ear regions for each of the living families of turtles as well as for those extinct families where this information is available. Additional figures, some of which are taken from the literature, show disarticulated elements, inner ear regions, arterial and nerve foramina and canals, and basicranial morphology. The other half of the figures are dorsal, lateral, and ventral views (also occipital views in many cases) of the skull in nearly all living genera of turtles and many extinct genera. The higher category classification used is that developed by Gaffney (1975d) and no taxonomic novelties are announced. A section of text provides a brief literature revew of chelonian systematics and cranial morphology and a listing (by family) of useful turtle skull illustrations from the literature. A revised glossary of anatomical terms and an index are included"--P. 69.Item The comparative osteology of the Triassic turtle Proganochelys. Bulletin of the AMNH ; no. 194([New York] : American Museum of Natural History, 1990) Gaffney, Eugene S."Proganochelys quenstedti Baur (= Triassochelys dux Jaekel, Stegochelys dux Jaekel) from the late Triassic Norian of Germany is the oldest well-preserved turtle. This paper describes the complete osteology of Proganochelys for the first time. The skull, shell, cervical vertebrae, caudal vertebrae, girdles, and limbs of Proganochelys are compared with primitive amniotes exemplified by Captorhinus, and with more advanced turtles, the pleurodires and cryptodires. The descriptions of Proganochelys are based on seven specimens, including three skull-shell associations. One of these specimens is an almost complete skeleton of what is hypothesized to be a young adult. Another skeleton is interpreted as a younger juvenile, while the remainder are interpreted as older adults. Proganochelys has the following chelonian synapomorphies: (1) Bony shell consisting of a carapace formed from costal bones with fused ribs, neural bones with fused thoracic vertebrae, and marginal bones; a plastron formed from interclavicle, clavicle, and five paired bones sutured together; carapace and plastron enclosing shoulder girdle and pelvic girdle. (2) Quadrate concave posteriorly and exposed laterally on cheek. (3) Postparietals and postfrontals absent. (4) Lacrimal bone small. (5) Maxilla, premaxilla, and dentary edentulous. (6) Stapes solid, rodlike, without foramen or processes. Proganochelys is hypothesized as the sister group to all other turtles. It retains the following primitive amniote characters absent in other turtles. (1) Supratemporal bone. (2) Lacrimal bone and duct. (3) Moveable basipterygoid articulation. (4) Middle ear without bony lateral wall. (5) Vomer paired. (6) Paroccipital process of opisthotic attached to braincase only at its distal end. Proganochelys has the following characters that are interpreted as autapomorphies. (1) Ventral tubercle on basioccipital. (2) Tail club. (3) Phalangeal formula (manus and pes) of 2-2-2-2-2. Interpretations of the depositional environment of Proganochelys combined with features of the limb morphology suggest that Proganochelys occupied fresh water as a bottom walker but was not exclusively aquatic or terrestrial"--P. 5.Item Cranial morphology of the baenid turtles. American Museum novitates ; no. 2737(New York, N.Y. : American Museum of Natural History, 1982) Gaffney, Eugene S."The family Baenidae is a group of extinct cryptodiran turtles known from more than a dozen well-preserved skulls from the Cretaceous, Paleocene, and Eocene. The baenid skull is characterized by sigificant generalized features in the skull roof and basicranium that are consistent with their hypothesized relationship as the sister group to the living cryptodires, the Eucryptodira. The arterial canals of the skull are preserved in enough specimens to conclude that baenids had an arterial pattern characterized by a large and well-developed canalis stapedio-temporalis and a small but persistent canalis caroticus lateralis"--P. [1].Item Cranial morphology of the European Jurassic turtles Portlandemys and Plesiochelys. Bulletin of the AMNH ; v. 157, article 6(New York : American Museum of Natural History, 1976) Gaffney, Eugene S."A theory of relationships is presented in which the Jurassic turtle genera Portlandemys and Plesiochelys are hypothesized as members of the monophyletic group Chelonioidea based on the possession of the following shared derived characters: 1) dorsum sellae high and separated from sella turcica and foramen anterius canalis carotici interni by prominent bone surface that usually has a sagittal ridge, 2) posterior part of sella turcica not concealed by overhanging dorsum sellae. The relationships of these genera within the Chelonioidea are more difficult to test owing to the fact that at present only the Recent forms are cranially as well known as Portlandemys and Plesiochelys. Nonetheless, I have suggested two contradictory hypotheses, one indicating Plesiochelys and Portlandemys as the sister group of the Dermochelyidae plus Cheloniidae, and the other indicating Plesiochelys as the sister group of the Toxochelyidae, Dermochelyidae, and Cheloniidae. The first hypothesis is consistent with derived characters of the palatine artery, whereas the second is consistent with postcranial derived characters"--p. 491.Item The cranial morphology of the extinct horned turtle, Meiolania platyceps, from the Pleistocene of Lord Howe Island, Australia. Bulletin of the AMNH ; v. 175, article 4([New York] : American Museum of Natural History, 1983) Gaffney, Eugene S."Meiolania platyceps is the best known of the extinct horned turtles of the Southern Hemisphere. Five skulls and hundreds of cranial elements have been collected from Pleistocene rocks on Lord Howe Island, New South Wales, over the past 100 years. The skull of Meiolania platyceps has the following features of the family Meiolaniidae: (1) Squamosal and supraoccipital produced into large posteriorly and posterolaterally directed processes that extend clear of the skull roof; (2) Medial plate of pterygoid separated ventrally from basisphenoid to form intrapterygoid slit. Meiolania platyceps can be identified as Crytodira on the possession of: (1) A processus trochlearis oticum on the anterior edge of the otic chamber; (2) A pterygoid that extends posteriorly between quadrate and braincase; (3) A descending process of the prefrontal that meets the vomer ventromedially. Within the Crytodira, Meiolania platyceps can be identified as Eucryptodira based on the posterior position of the foramen posterius canalis carotici interni"--P. 364.Item Domo de Zaza, an early Miocene vertebrate locality in south-central Cuba : with notes on the tectonic evolution of Puerto Rico and the Mona Passage. American Museum novitates ; no.3394(New York, NY : American Museum of Natural History, 2003) MacPhee, R. D. E.; Iturralde-Vinent, Manuel.; Gaffney, Eugene S.This report summarizes the results of paleontological and geological investigations carried out during the 1990s at Domo de Zaza, a late early Miocene vertebrate locality in south-central Cuba. Paleontologically, the most important result of fieldwork at Zaza was the first discovery of terrestrial mammals of Tertiary age in Cuba. Three terrestrial mammal taxa are now known from this locality--a megalonychid sloth (Imagocnus zazae), an isolobodontine capromyid rodent (Zazamys veronicae), and a platyrrhine primate (Paralouatta marianae, new species). In addition to these finds, a number of selachian, chelonian, crocodylian, cetacean, and sirenian remains have been recovered. Domo de Zaza is a low hill transected by a large artificial channel, the Canal de Zaza, whose walls provide an extensive exposure of Miocene sediments attributable to the Lagunitas Formation (Fm). This formation is laterally and vertically complex, showing evidence of at least four different depositional regimes. However, the sedimentary sequence indicates that all depositional phases took place within a broader episode of transgression. Estimated Burdigalian age (16.1-21.5 Ma) for Lagunitas Fm is based on the presence of marine invertebrate taxa corresponding to the late early Miocene Miogypsina-Soritiidae zone. The overall transgressive aspect of Lagunitas suggests rising sea level, possibly in correlation with a global onlap event. Within Burdigalian time, the most likely correlate is the eustatic rise centered on 17.5-18.5 Ma. Most of the vertebrate fossils were recovered from lagoonal and alluvial beds; those from lagoonal beds are exceptionally well preserved. The terrestrial facies displays evidence of paleosol formation, subaerial erosion, and plant life in the form of grass and palm pollen. Other evidence indicates that most of the present-day highlands of Cuba, including the Cordillera del Escambray near Zaza, have been continuously subaerial since the latter part of the late Eocene. Although no land vertebrate fossils of this age are known from Cuba, recent discoveries elsewhere in the Greater Antilles indicate that land vertebrates could have colonized landmasses in the Caribbean Basin as early as 33-36 Ma. Recently, marine geological data have been interpreted as showing that (1) the Mona Passage began to form in the early Oligocene, and (2) the Puerto Rico/Virgin Island block was entirely transgressed by shallow marine environments during the period between the late Oligocene and the early Pliocene. However, the seismic reflection profile evidence for an early Oligocene opening of the passage is ambiguous. Even if the separation of Puerto Rico and eastern Hispaniola occurred relatively early, it remains more probable than not that this happened in the medial Oligocene or even somewhat later (i.e., ≤30 Ma). On the other hand, the evidence is not at all ambiguous concerning the hypothesized mid-Cenozoic inundation of Puerto Rico: it did not happen. When available land and marine indicators are adequately compared, apparent contradictions in datasets can be evaluated and resolved. When examined in this way, the preponderance of evidence supports the contention that Puerto Rico has been an emergent landmass and has supported terrestrial environments continuously since the latest Eocene.Item Dracochelys : a new cryptodiran turtle from the early Cretaceous of China. American Museum novitates ; no. 3048(New York, N.Y. : American Museum of Natural History, 1992) Gaffney, Eugene S.; Ye, Xiangkui.Item An endocranial cast of the side-necked turtle, Bothremys, with a new reconstruction of the palate. American Museum novitates ; no. 2639(New York, N.Y. : American Museum of Natural History, 1977) Gaffney, Eugene S."A natural endocast of the skull of Bothremys, a pelomedusid pleurodire from the late Cretaceous (Magothy Formation of Cliffwood Beach, New Jersey) is unusual in preserving the orbital cavities as well as the brain cavity. The endocast provides new information on the basicranium, as well as the orbital and nasal cavities, and allows comparison with Recent pelomedusids"--P. [1].Item Evolution of the side-necked turtles : the families Bothremydidae, Euraxemydidae, and Araripemydidae ; Bulletin of the American Museum of Natural History, no. 300(New York, NY : American Museum of Natural History, 2006) Gaffney, Eugene S.; Tong, Haiyan.; Meylan, Peter A. (Peter Andre)Although pleurodires have been considered significantly less diverse than their sister group, the cryptodires, current discoveries show that pleurodires had a more complex and extensive evolutionary history than had been realized. Previously unknown radiations, particularly in the near-shore marine realm, are revealed by taxa with diverse cranial morphology, indicating many different feeding and sensory strategies. The pleurodire group that is changed the most by the new discoveries is its largest group, the hyperfamily Pelomedusoides. The hyperfamily Pelomedusoides now consists of the families Pelomedusidae, Podocnemididae, Bothremydidae, Araripemydidae, and Euraxemydidae, new family. The families Bothremydidae, Araripemydidae, and Euraxemydidae, new family, are documented with descriptions of skulls, lower jaws, and shells. The relationships of the family Podocnemididae to its sister taxa Hamadachelys and Brasilemys are recognized by placing them in the epifamily Podocnemidinura. The epifamily Podocnemidinura is the sister group to the family Bothremydidae, and together they form the superfamily Podocnemidoidea. The family Araripemydidae consists of one taxon, Araripemys barretoi, from the Aptian-Albian of Brazil. Description of new cranial material suggests that it is the sister group to all other Pelomedusoides or the sister group to the Pelomedusidae, but these relationships are only weakly supported. There is strong support for a multichotomy of Araripemys, Pelomedusidae, and remaining Pelomedusoides. Araripemys is characterized by very thin triturating surfaces and by a shell that lacks mesoplastra and has the first costals reaching the shell margin. The new family Euraxemydidae consists of two new genera: Euraxemys essweini, n. gen. et sp., from the Albian Santana Formation of Brazil, and Dirqadim schaefferi, n. gen. et sp., from the Cenomanian Kem Kem beds of Morocco. Members of the Euraxemydidae are united by the unique possession of a medial process of the quadrate partially covering the prootic and narrowly contacting a ventral process of the exoccipital, in contrast to all other pleurodires, which have either complete exposure or complete covering of the prootic ventrally. Furthermore, members have a ventral process of the exoccipital that is exposed at the lateral margin of the basioccipital in an elongate foot. The Euraxemydidae is hypothesized as the sister group to the superfamily Podocnemidoidea. The family Bothremydidae and the epifamily Podocnemidinura (consisting of the family Podocnemididae, Hamadachelys, and Brasilemys) are united as the superfamily Podocnemidoidea based on the possession of a quadrate-basioccipital contact, the complete or nearly complete ventral covering of the prootic, and the extension of the pectoral scales onto the entoplastron. The family Bothremydidae is a large and diverse group extending from the Albian to the Eocene in North and South America, Europe, Africa, and India. Its monophyly is supported by the presence of a wide exoccipital-quadrate contact, a eustachian tube separated from the incisura columellae auris usually by bone to form a bony canal for the stapes, absence of a fossa precolumellaris, a supraoccipital--quadrate contact (except in the tribe Taphrosphyini), and a posterior enlargement of the fossa orbitalis. Although there is a diversity of triturating surfaces within the family, primitively bothremydids have a posteriorly wide triturating surface with a significant palatine contribution in the upper jaw. The family Bothremydidae consists of four newly recognized, monophyletic groups: the tribes Kurmademydini, Cearachelyini, Bothremydini, and Taphrosphyini. The tribe Kurmademydini consists of two taxa: Kurmademys kallamedensis, from the Maastrichtian Kallamedu Formation of India, and Sankuchemys sethnai, from the Maastrichtian Intertrappean beds of India. The tribe Kurmademydini is characterized by extensive temporal and cheek emargination, a large fossa precolumellaris, and a small, anterior exposure of the prootic on the ventral surface. The tribe Kurmademydini is the sister group to the subfamily Bothremydinae (consisting of the tribes Cearachelyini, Bothremydini, and Taphrosphyini). Members of the subfamily Bothremydinae all possess a foramen stapedio-temporale that faces anteriorly. The tribe Cearachelyini consists of Cearachelys placidoi, from the Albian Santana Formation of Brazil, and Galianemys emringeri and Galianemys whitei, both from the Cenomanian Kem Kem beds of Morocco. The tribe Cearachelyini is characterized by a jugal retracted from the orbital margin and a fenestra postotica formed into a short slit. The tribe Cearachelyini is the sister group to the infrafamily Bothremydodda (consisting of the tribes Bothremydini and Taphrosphyini). The infrafamily Bothremydodda is characterized by a quadrate shelf formed below the cavum tympani, a foramen stapedio-temporale and foramen nervi trigemini that are very close together on the anterior face of the otic chamber, and a condylus occipitalis and occipital neck that are formed only by the exoccipitals. The tribe Bothremydini consists of Foxemys mechinorum, from the Campanian-Maastrichtian of France; Polysternon provinciale, from the Campanian of Europe; Zolhafah bella, from the Maastrichtian Dakla Formation of Egypt; Rosasia soutoi, from the Campanian-Maastrichtian of Portugal; Araiochelys hirayamai, n. gen. et sp., from the Danian phosphates of Ouled Abdoun Basin, Morocco; Bothremys cooki, from the Maastrichtian Navesink Formation of New Jersey; Bothremys maghrebiana, n. sp., from the Danian phosphates of Ouled Abdoun Basin, Morocco; Bothremys kellyi, n. sp., from the Ypresian phosphates of Ouled Abdoun Basin, Morocco; Bothremys arabicus, from the Santonian of Jordan; Chedighaii hutchisoni, n. gen. et sp., from the Campanian Kirtland Formation of New Mexico; and Chedighaii barberi, n. gen., from the Campanian of Arkansas, Alabama, Kansas, and New Jersey. The tribe Bothremydini is the sister group to the tribe Taphrosphyini. The tribe Taphrosphyini is characterized by the presence of a jugal-quadrate contact, the absence of a maxilla-quadratojugal contact, and the absence of a supraoccipital-quadrate contact. Members of the tribe Taphrosphyini have a considerable variety of triturating surfaces but they lack the wide, triangular surfaces typical of the other bothremydids. The tribe Taphrosphyini consists of Taphrosphys sulcatus, from the Danian Hornerstown Formation of New Jersey; Taphrosphys congolensis, from the Paleocene of Cabinda, west Africa; Taphrosphys ippolitoi, n. sp., from the Danian phosphates of the Ouled Abdoun Basin, Morocco; Labrostochelys galkini, n. gen. et sp., from the Danian phosphates of the Ouled Abdoun Basin, Morocco; Phosphatochelys tedfordi, from the Ypresian phosphates of the Ouled Abdoun Basin Morocco; Ummulisani rutgersensis, n. gen. et sp., from the Ypresian phosphates of the Ouled Abdoun Basin, Morocco; Rhothonemys brinkmani, n. gen. et sp., from the Paleogene phosphates of the Ouled Abdoun Basin, Morocco; Azabbaremys moragjonesi, from the Paleocene Teberemt Formation of Mali; Nigeremys gigantea, from the Maastrichtian of Niger; and Arenila krebsi, from the Maastrichtian Dakla Formation of Egypt. Among the Bothremydidae, the Taphrosphyini is the most diverse morphologically. The triturating surfaces show a wide range of variation. The long, narrow skull of Labrostochelys differs significantly from the very short skull of Phosphatochelys. Other genera, such as Azabbaremys and Arenila, have large and massive skulls, but without broadly expanded triturating surfaces, while Ummulisani has very narrow and deep labial ridges. The nasal regions of Taphrosphyini also show wide diversity. Rhothonemys has nasal openings and cavities more than twice the size of the orbits, but the nasal openings in Labrostochelys are smaller than the relatively small orbits. This diversity of Taphrosphyini skull morphology is mostly evident in the Paleogene of North Africa. A phylogenetic analysis of the core dataset of 41 taxa, 122 cranial characters, and 52 postcranial characters relies on comparative descriptions of these taxa. The analysis using PAUP results in one most parsimonious cladogram of 382 steps with a consistency index of 0.6. A Bremer decay analysis shows that the family Bothremydidae is strongly supported at five steps: the tribes Kurmademydini and Cearachelyini have an index of 2, and the tribe Taphrosphyini has an index of 3. The tribe Bothremydini becomes unresolved at one step and is the most weakly supported of these groups. The addition of selected shell-only taxa with low missing data values to the core dataset results in one equally parsimonious cladogram that is resolved as: (Proterochersis (Platychelyidae (Dortoka (Chelidae (Pelomedusidae + Araripemys) (Euraxemydidae (Teneremys (Podocnemididae + Hamadachelys + Brasilemys (Bothremydidae)))))))). A partitioned dataset consisting only of cranial characters (excluding all shell-only taxa) results in one equally parsimonious cladogram identical to the most parsimonious cladogram resulting from the whole dataset; however, a partitioned dataset consisting only of postcranial characters (excluding all skull-only taxa) resulted in 2704 trees, the consensus of which lacks resolution for nearly all Pelomedusoides, but which does resolve more basal pleurodires. When the skull morphology of the Bothremydidae is placed in the context of all other turtles, it becomes apparent that this family has the greatest range of skull forms of any turtle family yet known. In fact, the skull morphologies of many turtle families seem remarkably uniform in comparison (e.g., Testudinidae, Kinosternidae, Pelomedusidae, Trionychidae, Carettochelyidae)...Item Evolution of the side-necked turtles : the family Podocnemididae. (Bulletin of the American Museum of Natural History, no. 350)(American Museum of Natural History., 2011) Gaffney, Eugene S.; Meylan, Peter A. (Peter Andre); Wood, Roger Conant.; Simons, Elwyn L.; Campos, Diógenes de Almeida.The family Podocnemididae consists of 20 genera and 30 species considered here as valid and diagnosable by cranial characters. Three of these genera and eight species persist into the Recent fauna, barely reflecting the evolutionary diversity and distribution of the group. The family extends from the late Cretaceous to the Recent and occurs in North and South America, Europe, Asia, and Africa. A phylogenetic analysis utilizes 31 podocnemidid taxa (30 named and one unnamed; a total of 37 taxa analyzed includes outgroups) in the Podocnemididae that are analyzed using PAUP. The resulting consensus of nine equally parsimonious cladograms is the basis for a new classification of the family. The family Podocnemididae is reconfirmed as monophyletic, using the unique possession of a cavum pterygoidei formed by the basisphenoid, pterygoid, prootic, and quadrate, underlain by the pterygoid and basisphenoid, among other characters. Much of our resolution agrees with that of França and Langer (2006), which can be modified and restated as follows: (Bauruemys (vilavilensis (Podocnemis (Peltocephalus, Erymnochelys)))). The two clades proposed by Broin (1991) and Lapparent de Broin (2000b, 2001, 2003a, 2003b), designated by her as the "subfamily Podocnemidinae" and the "subfamily Erymnochelinae," are inconsistent with our analysis. In our analysis the "Podocnemidinae" (sensu Broin, 1991) is paraphyletic, and the "Erymnochelinae" (sensu Broin, 1991) could be made monophyletic, with the important addition of Peltocephalus (placed in the "Podocnemidinae" by Broin). We add a number of new taxa to the basal Podocnemididae and to the broad-jawed subtribe Stereogenyina. Within the family Podocnemididae Cope, 1868, the sister taxon to all other podocnemidids and recognized as the subfamily Bauruemydinae, new, is Bauruemys elegans (Suárez, 1969a), known from associated skulls and shells. All other podocnemidids, the redefined subfamily Podocnemidinae Cope, 1868, are united by a slight to absent temporal emargination, a completely closed foramen jugulare posterius, and saddle-shaped cervical centra (modified as a separate state in Erymnochelys). A basal group of Cretaceous-Paleocene podocnemidids that are the sister group to all remaining podocnemidids, here termed the infrafamily Peiropemydodda, consisting of two taxa from the late Cretaceous of Brazil, Peiropemys mezzalirai, n. gen. et sp., and Pricemys caiera, n. gen. et sp., and Lapparentemys vilavilensis (Broin, 1971), n. gen., from the Paleocene of Bolivia. The resolution of the basal members of the family is: (Bauruemys (Pricemys (Lapparentemys, Peiropemys)) (Infrafamily Podocnemidodda)). The remaining podocnemidids form the infrafamily Podocnemidodda Cope, 1868, new rank, and is characterized by the possession of a cheek emargination that does not reach above the level of the orbit, the medial expansion of the triturating surfaces with a median maxillary ridge present, and the presence of accessory ridges on the triturating surfaces. This group contains the living podocnemidids and a series of extinct forms, including the marine broad-jawed taxa. Within the Podocnemidodda, the genus Podocnemis is the sister group to all the remaining taxa, which is the magnatribe Erymnochelydand. When only the living fauna is considered our results show Podocnemis as the sister taxon to Erymnochelys plus Peltocephalus, in common with Williams (1954c), Franc¸a and Langer (2006), Meylan et al. (2009), and Cadena et al. (2010). With the fossil taxa present, the Erymnochelydand is united only by the small to absent cheek emargination. However, some of the fossil taxa (i.e., Caninemys, Dacquemys), are not known for a number of characters, and, if the analysis is reduced to include only the living species, Erymnochelys and Peltocephalus are united by a greater number of characters: cavum pterygoidei with enlarged anterior opening, so that the foramen cavernosum enters the roof of the cavum pterygoidei, orbits facing anterolaterally, jugal-quadrate contact present, cheek emargination slight to absent, horizontal occipital shelf absent, premaxillae reach apertura narium interna (also in some Podocnemis), supraoccipital roof exposure slight or absent, chorda tympani enclosed in processus retroarticularis, neural series extends to costal six, and axillary musk duct not in bridge. When one considers just the Recent genera, none of the published molecular results reproduce the Gaffney and Meylan (1988) and Lapparent de Broin (2000b) resolution of (Erymnochelys (Podocnemis, Peltocephalus)); rather these publications show a preference for the (Peltocephalus (Podocnemis, Erymnochelys)) arrangement, while we, in agreement with Franc¸a and Langer (2006) and the earlier version of the present data set, Meylan et al. (2009), place our marbles with the third alternative, (Podocnemis (Peltocephalus, Erymnochelys)). This latter hypothesis has a number of characters favoring its resolution, even when fossils are excluded. One of the more compelling ones is the large cavum pterygoidei with an enlarged anterior opening and the foramen cavernosum containing the lateral head vein, entering the roof of the cavum pterygoidei. Within the magnatribe Erymnochelydand are the following taxa: Caninemys, Dacquemys, unnamed genus UCMP 42008, Albertwoodemys, Turkanemys, Peltocephalus, Erymnochelys, Neochelys, Papoulemys, and the members of the tribe Stereogenyini (see below). The resolution of Caninemys within the Erymnochelydand is not strongly supported; in only one step it becomes a multichotomy with Podocnemis and the infrafamily Peiropemydodda. Neochelys, Papoulemys (possibly a synonym of Neochelys), and Dacquemys, however, are strongly supported as part of the magnatribe Erymnochelydand, as proposed earlier (Broin, 1991; Lapparent de Broin, 2000b, 2001, 2003a, 2003b). A new shell-based taxon, Albertwoodemys testudinum, n. gen. et sp., and an unnamed skull and shell, UCMP 42008, are united by a high-domed shell with thick lateral ridges along the plastron and the absence/fusion of the pectoral scales. The skull of UCMP 42008 agrees with that in Dacquemys in having large parietals and a supraoccipital covering the posterior margin. Lacking a skull, Albertwoodemys is not entered into the data set, but the skull-shell specimen of the closely related UCMP 42008 is in the analysis. New skull material identifiable as Neochelys has been discovered associated with shells of ‘‘Podocnemis’’ fajumensis Andrews, 1903, resulting in the new combination Neochelys fajumensis (Andrews, 1903). Neochelys has the Erymnochelydand synapomorphy of a large cavum pterygoidei with an enlarged anterior opening and the foramen cavernosum entering the roof of the cavum pterygoidei, as in Peltocephalus and Erymnochelys. The European Neochelys species are Eocene and the African Fayum species is Early Oligocene, extending both spatial and temporal ranges of the genus. The tribe Stereogenyini has a dorsal process of the palatine that reaches the frontal in the septum orbitotemporale, the fossa precolumellaris is absent, and both foramina nervi hypoglossi are combined and recessed in a short canal that opens on the occipital surface. Within the tribe Stereogenyini, Mogharemys blanckenhorni Dacque´ (1912), n. gen., is the sister taxon to the welldefined subtribe Stereogenyina. Two groups are recognized within the subtribe Stereogenyina. The infratribe Bairdemydita contains Bairdemys Gaffney and Wood, Latentemys plowdeni, n. gen. et sp., Cordichelys antiqua (Andrews, 1903), n. gen. The infratribe Stereogenyita contains Brontochelys gaffneyi (Wood, 1970), n. gen., Lemurchelys diasphax, n. gen. et sp., Shweboemys Swinton, 1939, and Stereogenys Andrews, 1901. The subtribe Stereogenyina is strongly supported by a secondary palate with a median cleft, unique among turtles, as well as other characters. While the other Podocnemididae were apparently freshwater species, there is evidence that many or all of the subtribe Stereogenyina were marine or near-shore marine. Compared with a group such as the Bothremydidae, we see in the evolution of the Podocnemididae, a relatively conservative series of South American paraphyletic taxa with an unusually persistent cranial as well as shell morphology, beginning in the Late Cretaceous with Bauruemys, Peiropemys, and Pricemys, and continuing with the Paleocene Lapparentemys, culminating in the Recent Podocnemis. A monophyletic Tertiary group with more geographic, taxonomic, and morphologic diversity, the magnatribe Erymnochelydand, contains African, European, Asian, and South American taxa, as well as a radiation of marine, broad-jawed species in the mid-Tertiary. The living remnants of the Erymnochelydand are the South American Peltocephalus and the African Erymnochelys, close relatives despite their current geographic separation.Item Fossil chelid turtles of Australia. American Museum novitates ; no. 2681(New York, N.Y. : American Museum of Natural History, 1979) Gaffney, Eugene S."Miocene freshwater deposits in the Tirari Desert region of South Australia have yielded the first skull material of chelid turtles in the fossil record. Partial skulls consisting of well preserved but disarticulated elements are very similar to the Recent genus Emydura, hypothesized by Gaffney (1977) as one of the more plesiomorphic of the Recent chelids. Well-preserved shells, cervical vertebrae, and limb elements are also consistent with this identification"--P. [1].Item Foxemys, a new side-necked turtle (Bothremydidae, Pelomedusoides) from the late Cretaceous of France. American Museum novitates ; no. 3251(New York, NY : American Museum of Natural History, 1998) Tong, Haiyan.; Gaffney, Eugene S.; Buffetaut, Eric."Associated skull and shell material from the late Cretaceous (probably Maastrichtian) of Fox Amphoux, southern France, is the new pleurodire taxon Foxemys mechinorum. Foxemys is a member of the pelomedusoid family Bothremydidae because it has these synapomorphies of that group: quadrate-basisphenoid covers prootic ventrally, stapedial canal opens anteriorly, precolumellar fossa absent, and eustachian tube separated from incisura columellae auris. A PAUP analysis of 23 characters and four bothremydid taxa has resulted in one cladogram showing Foxemys as the sister taxon to Taphrosphys, Bothremys, and Rosasia. Only one character, an open incisura columellae auris in Foxemys (closed in the three others), is the basis for this relationship, however, and it is considered to be weakly supported. The skull and shell of Foxemys are most similar to Polysternon provinciale from the Campanian of Villevayrac, France. The skull of Foxemys is similar to Polysternon in being wedge-shaped with a posteriorly expanded triturating surface. These genera differ from each other in that Polysternon has its mandibular condyles well anterior to the occipital condyle while in Foxemys these structures are nearly lined up transversely"--P. [1].
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