Complete Skull Research Articles

Smilodon populator et Protocyon troglodytes, deux superprédateurs du Pléistocène supérieur de la Serra da Capivara (Piauí) au Nordeste du Brésil

Among the fossiliferous sites of the Serra da Capivara national park region (South Eastern Piauí), two have yielded interesting remains of the two large Upper Pleistocene Carnivora, Protocyon troglodytes (Lund, 1838) and Smilodon populator Lund, 1842, the Toca da Cima dos Pilão and the Toca das Moendas, both in the municipality of Coronel José Dias. In these two caverns, numerous remains of preys were found, namely, for the Toca da Cima dos Pilão, the two peccaries Dicotyles tajacu and Tayassu pecari, the medium sized ground sloth Catonyx cuvieri and the giant armadillo Pampatherium; for the Toca das Moendas Palaeolama, Equids and Cervids add to that list. The two sites were used as dens by the two Carnivora species. In the Toca das Moendas, a near complete adult skull and a hemimandible of the large Canid P. troglodytes were found. The skull is the third ever known for the species. Its dimensions are very similar to those of a complete skull from the Toca da Boa Vista (Campo Formoso, Bahia, Brazil) described by Cartelle et Langguth (1999), and to those of an incomplete skull from the banks of the Bermejo River (Formosa Province, Argentina), described by Prevosti et al. (2005). It fits perfectly, like the teeth, with the anatomical characteristics of the species P. troglodytes: wide muzzle, short palate, very reduced and forwardly offset protocone of the P4/, etc. The dimensions of the cheek teeth correspond well with those of numerous teeth from Lagoa Santa (Minas Gerais, Brazil) of the Lund Collection preserved in the Zoological Museum of Copenhagen. The same site of Toca das Moendas yielded two left hemimandibles of the Machairodontine S. populator Lund, 1842, an adult and a very young ones. We study them together with other remarkable remains from the Toca da Cima dos Pilão, namely an adult upper canine and an adult hemimandible. The upper canine is one of the longest ever described for S. populator. The P/4 are somewhat longer than those of the Californian Smilodon fatalis (Leidy, 1868), and the M/1 are about of the same average length but somewhat narrower. The segment P/4-M/1 is relatively short. The dimensions of the upper canine and of the lower cheek teeth fit well with those of some teeth from Lagoa Santa (Minas Gerais, Brazil) and from Argentina preserved in the Zoological Museum of Copenhagen. We describe particularly the decidual lower dentition, badly known in that species. The rather weak milk canine has a piriform outline. The D/3 is constituted by a strong protoconid flanked with two small cuspids, an anterior and a posterior ones. The D/4 (deciduous carnassial) shows a strong paraconid followed by a higher protoconid and a small posterior cuspid. These milk teeth, without any abrasion mark, suggest that our young specimen was less than three month old.

A new notosuchian from the Late Cretaceous of Brazil and the phylogeny of advanced notosuchians.

A new notosuchian crocodyliform from the Late Cretaceous Bauru Group found in the southeastern State of São Paulo (Brazil) is described here. The new taxon, Caipirasuchus stenognathus, is referred as a new species of the recently erected genus Caipirasuchus within the clade Sphagesauridae based on a phylogenetic analysis of basal mesoeucrocodylians. Caipirasuchus stenognathus is represented by an almost complete skull and lower jaw that has autapomorphic characters that distinguish it from other species of Sphagesauridae. These autapomorphies include: maxilla forming part of the orbital margin (absence of lacrimal-jugal contact), nasal with smooth depressions on the posterior region close to the contact with the maxilla and lacrimal, postorbital with posterior palpebral facet that extends posteriorly underneath the ear-flap groove, and a distinct anterior process of the medial flange of the retroarticular process. Additionally, the new taxon lacks autapomorphic features described in other sphagesaurids. The phylogenetic analysis results in a monophyletic genus Caipirasuchus, that is the sister group of a clade fomed by Sphagesaurus huenei, Caryonosuchus pricei, and Armadillosuchus arrudai. Sphagesaurids also include a basal clade formed by Adamantinasuchus navae and Yacarerani boliviensis. Other notosuchian taxa, such as Mariliasuchus amarali, Labidiosuchus amicum, Notosuchus terrestris, and Morrinhosuchus luziae are successive sister taxa of Sphagesauridae, forming a clade of advanced notosuchians that are restricted to the Late Cretaceous of South America. These results contrast with most previous phylogenetic hypotheses of the group that depicted some members of Sphagesauridae as more closely related to baurusuchids, or found Asian (e.g., Chimaerasuchus) or African (Malawisuchus, Pakasuchus) forms nested within advanced notosuchians that are, according to our analysis, endemic of the Late Cretaceous of South America.

Hippopotamus lemerleiGrandidier, 1868 etHippopotamus madagascariensisGuldberg, 1883 (Mammalia, Hippopotamidae) : anatomie crânio-dentaire et révision systématique

ABSTRACT Hippopotamus lemerlei Grandidier, 1868 and Hippopotamus madagascariensis Guldberg, 1883 (Mammalia, Hippopotamidae): craniodental anatomy and systematic revision. Since the 1900s, the Museum d'Histoire naturelle of Toulouse has housed about 300 subfossil specimens of dwarf endemic hippopotamuses of Madagascar (Gallieni collection), neither described, nor determined so far. Thirteen cranial specimens, of which five complete skulls, two crania, a mandible and five fragments were described and measured. A comparative study of these specimens with those from the Natural History Museum, London, and from the Museum national d'Histoire naturelle, Paris was undertaken, complemented by the analysis of a relatively complex and disputed literature. This study allowed referring six skulls to Hippopotamus madagascariensis Guldberg, 1883 and one to H. lemerlei Grandidier, 1868. We propose six new differential diagnostic characters for these species (external sagittal crest larger, shorter, and flatter in H. lem...

A New Sebecid from the Paleogene of Brazil and the Crocodyliform Radiation after the K–Pg Boundary

A new crocodyliform, Sahitisuchus fluminensis gen. et sp. nov., is described based on a complete skull, lower jaw and anterior cervical vertebrae collected in the São José de Itaboraí Basin of Rio de Janeiro, Brazil. The specimen is one of the best preserved crocodyliforms from Paleocene deposits recovered so far and represents a sebecosuchian, one of the few clades that survived the Cretaceous-Paleogene biotic crisis. The new taxon is found in the same deposit as an alligatoroid, a group that experienced large diversification in the Paleogene. The sebecosuchian record suggests that after the Cretaceous-Paleogene biotic crisis, the less specialized members of this clade characterized by a higher number of teeth compared to the baurusuchid sebecosuchians survived, some having terrestrial habits while others developed a semi-aquatic life style (e.g., Lorosuchus). Starting in the Eocene, sebecid sebecosuchians became specialized with a more accentuated oreinirostry as observed in Sebecus and in Langstonia, but not showing the typical reduced dentition developed by the Cretaceous baurusuchid sebecosuchians. The basal position of Barinasuchus arveloi, a high-snouted Miocene sebecid, indicates the occurrence of an independent lineage sometime after the K-Pg biotic crisis that developed accentuated oreinirostry, suggesting a more complex history of the post-K-Pg crocodyliform radiation.

A new bernissartiid crocodyliform from the Lower Cretaceous Wessex Formation (Wealden Group, Barremian) of the Isle of Wight, southern England

A substantially complete skull of a small crocodyliform recently found on the foreshore near Yaverland on the southeast coast of the Isle of Wight, southern England is described. The locality, mode of preservation and associated matrix indicate that it is derived from one of the plant debris beds of the Lower Cretaceous Wessex Formation (Barremian, Wealden Group). The dentition, unique among crocodyliforms, serves to confirm that the specimen is referable to the, until now, monotypic family Bernissartiidae. Apomorphies, including placement of the choana entirely within the pterygoids and disposition of cranial sutures demonstrate that the Isle of Wight skull cannot be referred to Bernissartia fagesii, known from contemporaneous strata. Furthermore, these characters indicate that the specimen should not be referred to a new species of Bernissartia. It is therefore placed in a new genus and species, Koumpiodontosuchus aprosdokiti. The systematic position of Bernissartiidae, and characters used to diagnose E...

Photographic Atlas and Three-Dimensional Reconstruction of the Holotype Skull of Euhelopus zdanskyi with Description of Additional Cranial Elements

Background Euhelopus zdanskyi is one of relatively few sauropod taxa known from an almost complete skull and mandible. Recent phylogenetic analyses suggest that Euhelopus is a somphospondylan titanosauriform, and that it is a member of the clade (Euhelopodidae) which is the sister taxon to the hugely successful, dominantly Cretaceous sauropod group Titanosauria.Methodology/Principal FindingsThe skull elements of Euhelopus were CT scanned at Uppsala Akademiska Sjukhuset. Three-dimensional models of the elements were constructed from the DICOM data using Mimics 14.0, InVesalius 3.0, and GeoMagic Studio 2012, the skull was rearticulated in Rhinoceros 4.0, and the final version was rendered in GeoMagic Studio 2012.Conclusions/SignificanceThe fact that relatively complete sauropod skulls are so rare in the fossil record, particularly among titanosauriforms, means that the skulls that are known should be as thoroughly described and well-illustrated as possible. This contribution supplements previous descriptions of the cranial elements of Euhelopus, one of the few euhelopodid taxa for which cranial material is known, by presenting a comprehensive photographic atlas of the skull elements to facilitate a better understanding of their morphology. We describe several elements which have been overlooked in past studies of Euhelopus, and also provide as accurate a reconstruction of the skull as possible (in the absence of the braincase), the most significant components of which are the articulations of the palate and the mandible.

New species of Tsaidamotherium (Bovidae, Artiodactyla) from China sheds new light on the skull morphology and systematics of the genus

A new species of Tsaidamotherium (Bovidae, Artiodactyla), T. brevirostrum, described here represents only the second discovery of the genus. Tsaidamotherium is a mid-sized late Miocene bovid with an odd-looking plate-like horn-core apparatus so far known only from northwestern China. The holotype of T. brevirostrum is a cranial part of skull from the Liushu Formation (late Miocene) of the Linxia Basin. The new species differs from the type species, T. bohlini, mainly in horn-core morphology, having the frontal horn-cores proper much smaller and less distinctly separated from the plate-shaped posterior portion. Furthermore, the new species has smaller frontal sinuses, but a thicker layer of compact bone beneath the horn-core apparatus as seen in frontal section. A complete skull with a smaller horn-core apparatus is considered to represent a female individual of T. brevirostrum. The facial part of the skull, which is first known for this genus, is very short and high, with a high nasal cavity, strongly retracted nasals, and shortened premaxillae and premolar rows. All this probably suggests that the animal with an enlarged nasal cavity, like the modern Saiga and Budorcas, may have had a special adaptation to the high plateau environment.

A remarkable short-snouted horned dinosaur from the Late Cretaceous (late Campanian) of southern Laramidia

The fossil record of centrosaurine ceratopsids is largely restricted to the northern region of western North America (Alberta, Montana and Alaska). Exceptions consist of single taxa from Utah (Diabloceratops) and China (Sinoceratops), plus otherwise fragmentary remains from the southern Western Interior of North America. Here, we describe a remarkable new taxon, Nasutoceratops titusi n. gen. et sp., from the late Campanian Kaiparowits Formation of Utah, represented by multiple specimens, including a nearly complete skull and partial postcranial skeleton. Autapomorphies include an enlarged narial region, pneumatic nasal ornamentation, abbreviated snout and elongate, rostrolaterally directed supraorbital horncores. The subrectangular parietosquamosal frill is relatively unadorned and broadest in the mid-region. A phylogenetic analysis indicates that Nasutoceratops is the sister taxon to Avaceratops, and that a previously unknown subclade of centrosaurines branched off early in the group's history and persisted for several million years during the late Campanian. As the first well-represented southern centrosaurine comparable in age to the bulk of northern forms, Nasutoceratops provides strong support for the provincialism hypothesis, which posits that Laramidia—the western landmass formed by inundation of the central region of North America by the Western Interior Seaway—hosted at least two coeval dinosaur communities for over a million years of late Campanian time.

The Chacoan peccary, Catagonus wagneri (Mammalia, Tayassuidae), in the late Pleistocene (northern Uruguay, South America): paleoecological and paleobiogeographic considerations

Catagonus wagneri has the most restricted geographical distribution among extant Tayassuidae and inhabited semi-arid thorny forests of dry Chaco in Paraguay, Bolivia and Argentina. Until now, C. wagneri has only been recorded in archaeological, pre-Hispanic deposits from the Santiago del Estero Province, Argentina. A new partially complete skull from the Sopas Formation (Late Pleistocene; Uruguay) is identified as C. wagneri. This is the only fossil record of the species which extends its biochron until the late Pleistocene, and the first one substantially far from its current range; the first fossil record of the species in Uruguay; the most complete fossil material of the species; and it provides relevant ecological and climatic information. According to the ecological and climatic available information of C. wagneri, the presence of this mammal in the late Pleistocene of northern Uruguay indicates a warm climate and arid to semi-arid environments. Even though not associated with the fossil remains of C. wagneri, some mammals included in the sedimentary levels of the Sopas Formation also suggest arid to semi-arid environments. Climatic changes, in particular in the late Pleistocene and Holocene, could be invoked to explain modifications of its geographic range.http://zoobank.org/ECF04BCF-8246-4F11-AAB8-5FAA9F437BDA

New remains ofMachimosaurus hugiivon Meyer, 1837 (Crocodilia, Thalattosuchia) from the Kimmeridgian of Germany

Abstract. The fourth complete skull of the marine crocodilian Machimosaurus von Meyer, 1837 is hereby described together with an associated complete mandible and disarticulated postcranial elements from the Kimmeridgian of Neuffen, Germany. Although the genus has been described fairly recently on the basis of two nearly complete skulls, their state of preservation did not allow a thorough examination of the entire skull anatomy. Here, we add new information with the description of nicely preserved cranial and mandibular elements of a single individual attributable to Machimosaurus hugii von Meyer, 1837. The diagnosis is updated for the genus and for the species M. hugii and challenges the validity of the second species M. mosae (Lienard, 1876). Moreover, previous assumption that Steneosaurus obtusidens Andrews, 1913 is a junior synonym of Machimosaurus hugii is not supported by our observations. Notably, M. hugii differs from S. obtusidens by a lower tooth count, the morphology of the dentition, the shape of the supratemporal fenestrae and the absence of an antorbital fenestra. Comparative anatomy and a phylogenetic analysis show that Machimosaurus is more closely related to the genus Steneosaurus than to Teleosaurus cadomensis (Lamouroux, 1820). doi: 10.1002/mmng.201300009

New remains of <i.Machimosaurus hugii</i> von Meyer, 1837 (Crocodilia, Thalattosuchia) from the Kimmeridgian of Germany

The fourth complete skull of the marine crocodilian <i>Machimosaurus</i> von Meyer, 1837 is hereby described together with an associated complete mandible and disarticulated postcranial elements from the Kimmeridgian of Neuffen, Germany. Although the genus has been described fairly recently on the basis of two nearly complete skulls, their state of preservation did not allow a thorough examination of the entire skull anatomy. Here, we add new information with the description of nicely preserved cranial and mandibular elements of a single individual attributable to <i>Machimosaurus hugii</i> von Meyer, 1837. The diagnosis is updated for the genus and for the species <i>M. hugii</i> and challenges the validity of the second species <i>M. mosae</i> (Liénard, 1876). Moreover, previous assumption that <i>Steneosaurus obtusidens</i> Andrews, 1913 is a junior synonym of <i>Machimosaurus hugii</i> is not supported by our observations. Notably, <i>M. hugii</i> differs from <i>S. obtusidens</i> by a lower tooth count, the morphology of the dentition, the shape of the supratemporal fenestrae and the absence of an antorbital fenestra. Comparative anatomy and a phylogenetic analysis show that <i>Machimosaurus</i> is more closely related to the genus <i>Steneosaurus</i> than to <i>Teleosaurus cadomensis</i> (Lamouroux, 1820). <br><br> doi:<a href="http://dx.doi.org/10.1002/mmng.201300009" target="_blank">10.1002/mmng.201300009</a>

A new neosuchian with Asian affinities from the Jurassic of northeastern Brazil

Phylogenetic relationships near the origin of extant crocodylians are weakly supported, and this lack of resolution makes for poor estimates of taxonomic and morphological diversity. Previously known taxa are found throughout the Cretaceous in Laurasia and at a few sites from Brazil, Australia, and northern Africa. Here, we report Batrachomimus pastosbonensis gen. et sp. nov. from the Late Jurassic of northeastern Brazil, which is deeply nested within Neosuchia and associated to the Cretaceous Asian paralligatorids. The new taxon predates all other members of Paralligatoridae and its immediate sister group (including Eusuchia) by 30 million years. A nearly complete skull, osteoderms, and limb bones were recovered, and autapomorphies of B. pastosbonensis include a scalloped lateral margin of the rostrum in dorsal view, unsculpted alveolar margin at the caudalmost portion of the maxilla, blunt lateral prongs on the jugal at the base of the postorbital bar, hourglass shaped choanae, and pterygoid choanal septum extended between the palatal shelves of the palatines. The crocodyloid-like skull proportions and the slender, conical teeth suggest an amphibious and piscivorous life history to this 1 m long animal.

Osteological redescription of the skull ofMicrocleidus homalospondylus(Sauropterygia, Plesiosauria) from the Lower Jurassic of England

The plesiosaur specimen NHMUK 36184 from the Lower Jurassic of Whitby, Yorkshire and kept in the Natural History Museum of London, comprises an almost entire skeleton with nearly complete skull. It was described as one of two syntypes ofPlesiosaurus homalospondylusby Owen, and selected as the lectotype by Lydekker. Extensive preparation of the skull has revealed it as one of the most complete and best-preserved Jurassic plesiosaurian skulls known, and its description adds much-needed data to our knowledge of the cranial osteology of the Plesiosauria. The three-dimensional preservation permits a relatively reliable reconstruction of its form.Microcleidus homalospondylusdisplays an interesting combination of cranial characters present in Jurassic plesiosauroids and Cretaceous Elasmosauridea. Its snout presents a very distinctive sculpture; the first pair of premaxillae teeth are extremely reduced; the frontal is partially overlain by the premaxillae, contacts the pineal foramen but does not contact the temporal fenestra; the jugal does not contact the orbit nor the temporal fenestra; the squamosal contacts the postorbital but not the maxilla and presents a bulb; the postfrontal contacts the posterolateral orbit margin; the anterior interpterygoid vacuity is absent; the pterygoids meet posterior to the posterior interpterygoid vacuities and are pierced by a foramen at this level; the quadrate ramus of the pterygoid presents a ventromedial flange; the parasphenoid is crested; the epipterygoid contacts the parietal; the paroccipital process is spatulate distally; the prootic presents an anteroventral process; the mandibular symphysis is keeled and bears four pairs of teeth.Microcleidusappears very similar toHydrorionandOccitanosaurus, and the three taxa share a great number of plesiomorphic characters with basal plesiosaurians and pliosauroids.

A new skeleton of the giant hedgehog Deinogalerix from the Miocene of Gargano, southern Italy

ABSTRACT The giant Miocene erinaceid Deinogalerix from the Gargano paleoisland, southern Italy, represents one of the most spectacular cases of insular adaptation among terrestrial mammals. The type species of this genus, Deinogalerix koenigswaldi, was described for the first time early in the 1970s based on a nearly complete skeleton and the limits and composition of the genus were subsequently defined based on a large number of disarticulated remains. Recent excavations in the Gargano area led to the discovery of a second partially complete skeleton of Deinogalerix koenigswaldi. This material, which is described herein, consists of a well-preserved nearly complete skull and a large portion of the postcranial skeleton. As a result of its excellent preservation, this material allowed the description of previously unrecognized morphological features of the braincase, tympanic region, and forelimb. Finally, based on a comparative analysis of the skeletal features of Deinogalerix, its affinities within the Erinaceidae have been discussed. Several features observed on the skeleton documented in this paper conclusively demonstrate that this giant hedgehog is a member of the subfamily Galericinae and, more particularly, of the extinct tribe Galericini.

Species of the genus Martes in the northwest of the Russian Plain in the Holocene

The problem of a sable (M. zibellina) and a pine marten (M. martes) potential cohabitation in the northwest of Eastern Europe was resolved using methods of multidimensional data analysis for the first time. The skulls (n = 48) and mandibles (n = 194) of representatives of the genus Martes from ten archaeological sites of the middle Holocene (Neolithic camps) and late Holocene (Iron Age settlements) of Onega Lake region and upper reaches of Western Dvina River region were studied. 18 complete skulls and large fragments of skulls were identified morphologically as M. martes remains. 42 mandibles of M. martes from eight middle and late Holocene sites of Western Dvina River region and two mandibles of M. zibellina from two middle Holocene sites of Onega Lake region were identified using discriminant analysis methods (8 – 15 metrical characters in each model).

A new, richly fossiliferous member comprised of tidal deposits in the Upper Cretaceous Maevarano Formation, northwestern Madagascar

A new member of the Upper Cretaceous (Maastrichtian) Maevarano Formation is proposed to accommodate a distinctive succession of strata exposed along the shores of Lac Kinkony in northwestern Madagascar. The new Lac Kinkony Member overlies fully terrestrial sandstones of the Anembalemba Member of the Maevarano Formation, and is capped by marine dolostones of the Berivotra Formation. In the stratotype section, the base of the Lac Kinkony Member consists of siltstone interbeds that host networks of Ophiomorpha. Siltstone facies pass up-section to distinctive white sandstones packed with dolomitic mud matrix that exhibit rhythmic clay drapes, flaser and wavy bedding, and oppositely-oriented ripples developed on the toes of larger foresets. Thin flat interbeds of microgranular dolostone and claystone comprise the uppermost facies of the Lac Kinkony Member, and a laterally traceable ravinement bed mantled by cobbles of rounded dolostone marks the contact with the superjacent Berivotra Formation. Deposits of the Lac Kinkony Member are interpreted to represent siliciclastic and carbonate tidal flats dissected by tidally-influenced rivers. Vertebrate fossils are abundantly preserved in these coastal deposits, and are locally concentrated in microfossil bonebeds that have the potential to yield thousands of small identifiable specimens. In addition to many taxa already known from the Maevarano Formation, the Lac Kinkony Member has yielded a wealth of phyllodontid albuloid fish skull elements, the distal humerus of a new frog taxon, five vertebrae representing two new snakes, a tooth of a possible dromaeosaurid, and a complete skull of a new mammal. The discovery of several new vertebrate taxa from this new member reflects the fact that it samples a previously unsampled nearshore, peritidal paleoenvironment in the Late Cretaceous of Madagascar.

HYDRODYNAMIC BEHAVIORS OF PACHYCEPHALOSAURID DOMES IN CONTROLLED FLUVIAL SETTINGS: A CASE STUDY IN EXPERIMENTAL DINOSAUR TAPHONOMY

The hydrodynamic behaviors of isolated dinosaur bones have been largely overlooked in the paleontological literature. Investigations into the hydrodynamic properties of dinosaur remains with unique taphonomic signatures, such as pachycephalosaurid frontoparietal domes, have the potential to aid in the interpretation of preservation for skeletal elements for which modern analogues are not available. For this study, a series of transport experiments were conducted to assess the entrainment velocities and settling orientations of a collection of pachycephalosaurid specimens. Casts of four pachycephalosaurid frontoparietal domes and skulls were composed of a urethane resin with a comparable average density to compact and cancellous bone, and placed in a flume with manual velocity control. Data were recorded for competent velocity, transport distance, and settling orientations upon resting and burial of specimens for 35 trials per cast. Though specimens vary considerably in mass, the results suggest specimen shape has a greater influence on transport and hydrodynamic behavior than size; significantly lower velocities are required to transport complete skulls than isolated domes. Resting and burial orientations of specimens vary significantly for domes and complete skulls. The highly variable transport velocities and settling orientations of pachycephalosaurid crania offer insight into pachycephalosaurid taphonomy and illustrate the importance of future taphonomic studies on large fossil vertebrate remains.

Septidelphis morii, n. gen. et sp., from the Pliocene of Italy: new evidence of the explosive radiation of true dolphins (Odontoceti, Delphinidae)

ABSTRACT A new genus and species of true dolphin (Delphinidae), Septidelphis morii, is described on the basis of a partial fossil skeleton (almost complete skull, mandibles, teeth, hyoid bones, 17 vertebrae, several ribs, sternum and sternal ribs), originally belonging to an immature subadult animal, from the late Zanclean–early Piacenzian (Pliocene) marine sands of Piedmont (northern Italy). This new dolphin is characterized by an extreme posterior widening of the dorsal opening of the mesorostral canal and shares with Astadelphis, Etruridelphis, Sousa, and Steno the following combination of characters: (1) long and narrow rostrum; (2) wide premaxillae at the middle of rostrum; and (3) condylobasal length reaching at least 550 mm. A phylogenetic analysis using a molecular scaffold approach placed Septidelphis inside the delphinines in a more apical position than Sousa but basal to the clade formed by all other extant delphinines. Etruridelphis is positioned as the sister taxon of Septidelphis, and Astadelphis is positioned as the sister taxon of a larger grouping that includes this clade and all extant delphinines except Sousa. The phylogenetic position of Septidelphis inside Delphinidae and its stratigraphical age (3.81–3.19 Ma) are consistent with estimated divergence dates reported in a recent molecular study, whereas the first occurrence of Etruridelphis, dated to slightly before 3.98 Ma, could represent a minimal age for the origin of the delphinines and a potential calibration point for molecular clock studies. Septidelphis corroborates the explosive radiation and fast speciation-extinction rate of the delphinids during the Pliocene–Pleistocene. SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP

New specimens of ‘Crocodylus’ pigotti (Crocodylidae) from Rusinga Island, Kenya, and generic reallocation of the species

ABSTRACT ‘Crocodylus’ pigotti is a relatively small crocodylid from the Miocene of Rusinga Island in Lake Victoria, Kenya. Known only from one relatively complete skull and limited, fragmentary, referred material, ‘Crocodylus’ pigotti lacks a detailed description. Moreover, recent analyses have shown ‘Crocodylus’ pigotti to be an osteolaemine crocodylid, more closely related to the extant dwarf crocodiles (Osteolaemus) than to true Crocodylus. Here, we describe numerous new remains of ‘Crocodylus’ pigotti recovered from localities within the Fossil Bed Member of the Hiwegi Formation at Kaswanga Point, Rusinga Island. We recovered parts of several individuals and report on previously unknown parts of the anatomy, provide an updated phylogenetic analysis, and reallocate the species ‘Crocodylus’ pigotti to a new genus, Brochuchus. SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP

New information on amphibamids (Tetrapoda, Temnospondyli) from Richards Spur (Fort Sill), Oklahoma

ABSTRACT A nearly complete amphibamid skull from the Richards Spur locality in Oklahoma is demonstrated to be a new species of Tersomius. This new species has a mosaic of features seen in other amphibamids, and appears to fall on the Amphibamus side of the amphibamid basal dichotomy of some authors. This specimen also calls into question the validity of the Tersomius assignment of a large specimen from the Texas Red Beds. One feature of note is the presence of a weakly bicuspid fang on one of the vomers. This poorly developed feature is present only on an unattached replacement cusp, and appears to have been rapidly worn away through use. This is the first potential bicuspid palatal fang known from an amphibamid. A second partial skull is assigned to the recently described species Pasawioops mayi. A micro-computed tomographic reconstruction shows a prominent ventral flange of the nasal that meets a counterpart from the prefrontal and palatine to wall the nasal capsule posteriorly. The nasolacrimal canal shows the three openings in the orbit quickly converge to pass rostrally as a single canal except for a mysterious lateral diverticulation that has a superficial exposure on the lacrimal. Both skulls preserve a pars palatina of the premaxilla, in common with batrachians, and the Pasawioops specimen also preserves a prominent palatal process of the premaxilla, a frog synapomorphy. Richards Spur preserves one of the most diverse amphibamid faunas in the world, with three species described so far. SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP