A nearly complete specimen of a new coelacanth is described from the Oxfordian of Burgundy, France. Wenzia latimerae, gen. et sp. nov., shares unique features with both the extant coelacanth Latimeria and the Mesozoic coelacanth Macropoma. It displays a unique combination of primitive characters (such as the presence of a spiracular bone and postparietal pit-lines), and derived characters (such as a postparietal shield with raised areas and very short relatively to the parietonasal shield; a consolidated snout bearing large tubercles; a deeply excavated postorbital with a long and tubular ventral expansion; a squamosal with an anterior expansion for the jugal sensory canal). A cladistic analysis suggests that the new species is the fossil sister taxon to Latimeria, but this close relationship is weakly supported. Nevertheless, Wenzia latimerae belongs with confidence to the Latimeriidae. The new specimen also provides information on the structure of the calcified plates of the ossified swim bladder, as well as on the structure of the muscle fibres. Part of the diet of this marine coelacanth is known thanks to the presence of a small crustacean in its stomach contents.

Ecocarpia ningmingensis, gen. et sp. nov., a fossil cyprinid fish from the mid-Tertiary of the Ningming Basin, Guangxi Zhuang Autonomous Region, China, is similar to cultrins in having a slender body, terminal or slightly superterminal mouth, comparatively long anal fin base, and reduced bifurcation of the pelvic bone. The morphology of the pharyngeal teeth in the new taxon, however, is different from that of cultrins but very similar to that of the xenocyprinins: the first row of pharyngeal teeth is six or even seven in number, and all are laterally compressed, with a flat, smooth, lateral face and a long, narrow grinding surface that tapers slightly towards the apex. The only dental difference between Ecocarpia ningmingensis and xenocyprinins is the presence of a tiny and slightly recurved tip on some of the teeth in Ecocarpia, a condition that is similar to cultrins. Our phylogenetic study shows that Ecocarpia ningmingensis, cultrins and xenocyprinins form a monophyletic group, characterized by a single synapomorphy: reduction of the bifurcation of the pelvic bone. This grouping further supports the close relationship between cultrins and xenocyprinins.

The small temnospondyl Micropholis stowi from the Lower Triassic Lystrosaurus Assemblage Zone (Karoo Basin, South Africa) is redescribed on the basis of a larger sample of specimens, revealing a range of previously unknown anatomical features. Micropholis is recognized as a member of the Amphibamidae, representing both the last occurrence and the only Gondwanan member of this clade. (1) The largest specimens have an elongated narrow snout, larger otic notches, prominent quadrate processes, and wide cheeks giving the skull a marked lateral curvature. (2) Palpebral ossifications include a fabric of numerous polygonal ossicles contouring the size and position of the eyeballs. (3) The palate houses large fangs with inwardly curving crowns, an elaborate basicranial region resembling closely that of Amphibamus and Doleserpeton, and an extremely reduced rod-like palatine and ectopterygoid approaching the derived condition seen in other amphibamids. (4) In the postcranial skeleton, the greatly extended transverse processes, the morphology of the interclavicle and scapulocoracoid, and the structure of the pelvis and tail are characteristic features of Micropholis some of which are quite similar to the condition in Eoscopus and Platyrhinops. It is evident that two morphs of Micropholis, which differ in skull width and palatal dentition, are present in the Karoo Basin.

Phylogenetic analysis suggests Micropholis to be nested within the amphibamid dissorophoids as the basal-most taxon. Within the Amphibamidae, Doleserpeton and Amphibamus are sister groups, nested with successive sister taxa Platyrhinops and Eoscopus. In particular, the miniaturized genera Doleserpeton and Amphibamus share a range of derived character-states with Micropholis, but the latter lacks the pedicellate dentition and has a more plesiomorphic posterior skull table and parasphenoid, suggesting that some of the shared derived states may have been acquired independently during the long isolated evolution of the Micropholis lineage in the Southern Hemisphere. In the present analysis, Micromelerpeton is the most basal offshoot of the dissorophoids, followed by a grade towards amphibamids formed by the following successive sister groups (from the base crownwards): (1) the trematopids, (2) Ecolsonia, and (3) the Dissorophidae, the latter being the sister taxon of all analyzed amphibamids.

A fossil salamander is described based on specimens from a Lower Cretaceous deposit near Ningcheng, Inner Mongolia, China. Recently reported as Jeholotriton paradoxus, this form represents a neotenic salamander as indicated by larval features such as external gills, tooth-bearing coronoids, pterygoids with anteromedially oriented anterior processes, and underdeveloped maxillae, in combination with adult features such as extensive medial contact of the nasals and posteriorly directed tooth rows in the palate. This taxon is distinguished from other Mesozoic salamanders by having 15–16 presacrals, proximally expanded unicapitate ribs, vomers with large tooth patches anteriorly and longitudinal dentigerous bars posteriorly, large nasals with no anterior notch, frontals with no anterolateral extension, premaxillae with distinct alary processes, short transverse processes on the vertebrae, and phalangeal formulae of 2-2-3-2 for the manus and 2-2-3-3-2 for the pes. Including Laccotriton, Liaoxitriton, Sinerpeton and Chunerpeton, five taxa of Mesozoic salamander have now been found in China. Jeholotriton has especially well-preserved impressions of articulated skeletons, a type of preservation that is uncommon in Mesozoic strata throughout the world and provides important anatomical details of this early salamander. The great diversity of fossil salamanders from the late Mesozoic of northeastern China implies that East Asia was an important center for the early evolution of urodeles.

Numerous fossil pipoid frogs recovered from Late Cretaceous deposits of a closed crater-lake of Late Cretaceous age in the Marydale District of South Africa are described and referred to a new genus and species of pipoid anuran. The fossils include larvae and adult frogs that are thought to have been killed en masse following breakdown of the thermal stratification or possibly by CO₂ degassing from the underlying magma. A cladistic analysis of fossil and extant pipoid frogs based on 49 osteological characters reveals the new taxon to be a member of the pipinomorph clade, which includes the Late Cretaceous Eoxenopoides reuningi also from South Africa, fossil and Recent hymenochirines from Africa, and living Pipa from South America. The new taxon is distinctly larger than Eoxenopoides and further differs from this contemporaneous taxon in having an antorbital process on the maxilla and seven presacral vertebrae, with the first presacral being formed by fusion of Presacrals I and II. The curved shape of the ventral part of the braincase distinguishes this frog from hymenochirines, Palaeobatrachus, and Eoxenopoides. The new anuran is distinguished from the Israeli fossil Thoraciliacus of about the same age by the possession of a conch-shaped tympanosquamosal bone, a short jaw, and fusion of the sacrum and urostyle.

The ilium is widely considered to be the single best element upon which to base the identification of fossil anurans when isolated bones are all that are available. I tested the diagnostic utility of continuous and discrete ilial characters for toads of the genus Bufo by evaluating their distribution among an expanded taxonomic sample of 27 extant North American species. Support for species-level identifications and for the identification of traditionally recognized species groups based on ilial characters alone was assessed.

Results indicate that no distinctive morphologies in the ilium of extant North American Bufo are known that permit a species-level identification or the diagnosis of any traditionally recognized species group. Two of the ten included extinct species, B. holmani and B. kuhrei, do contain ilial characters that fall outside the observed range of the examined extant species. The fact that both morphometric and discrete characters fail to support species-level identification of isolated ilia of extant Bufo indicates that identifications should be restricted to higher taxonomic levels until new ilial characters are established. Potentially informative characters should be tested against a comparative sample that reflects clade diversity rather than one that reflects our geographic and/or temporal assumptions. This approach helps to avoid circularity if the identifications are used subsequently in analyses of faunal dynamics.

A new eureptile, Concordia cunninghami, gen. et sp. nov., is described from the Upper Pennsylvanian Hamilton-Fossillagerstätte, Kansas, U.S.A. The new taxon is currently known on the basis of two well-preserved skulls. A phylogenetic analysis groups Concordia consistently with captorhinids; the holotype, therefore, can be regarded as the oldest record of a captorhinid reptile, and the first one from the Carboniferous. Concordia reduces to a notable extent the stratigraphic gap between captorhinids and the first appearance of other eureptiles. Furthermore, the new taxon is the third known amniote representative from the Hamilton fauna, improving our knowledge of Late Carboniferous terrestrial communities.

New and more complete specimens of pleurodiran turtles from the Salamanca Formation (lower Paleocene) of Patagonia are described. The shell sculpturing, size, and morphology of these specimens match with the characteristics of the largest of Staesche's species (?Najadochelys maior Staesche, 1929 and Osteopygis sculptus Staesche, 1929). Osteopygis sculptus is considered a junior synonym of ?Najadochelys maior. This taxon is the only valid one of Staesche's large species, and is assigned to the chelid genus Yaminuechelys de la Fuente et al. 2001 as Y. maior (Staesche, 1929) new comb. The phylogenetic hypothesis proposed supports a sister-group relationship between Yaminuechelys and Hydromedusa. This clade plus the Australasian genus Chelodina form a monophyletic group supported by cranial and postcranial derived characters, and differentiated in Patagonia at least as early as the upper Cretaceous.

Most of the Cretaceous ichthyosaurian materials are referable to the single genus Platypterygius, which includes seven species. Although Cretaceous ichthyosaurs were probably cosmopolitan in their distribution, South American records are scarce. In recent revisions, the name Platypterygius hauthali has been retained for Early Cretaceous material from South America, but no specific diagnosis has been provided. The species P. hauthali was proposed on the basis of fragmentary material from the Neocomian of Santa Cruz Province (Patagonia, Argentina). However, analysis of the forefin features of the holotype shows that the pattern of carpal ossifications is different from that of other species of the genus and, furthermore, that this pattern is sufficient for specific diagnosis. Based on these data and additional findings of ichthyosaurs in Neuquén, Argentina, it can be concluded that there are three valid ichthyosaur taxa present in the Early Cretaceous of South America: Caypullisaurus bonapartei (Berriasian of Neuquén, Argentina), Platypterygius hauthali (Early Barremian of Santa Cruz, Argentina) and P. sachicarum (Barrenian-Aptian of Colombia).

A newly prepared elasmosaurid plesiosaur specimen, from the Haumurian (Upper Cretaceous) Conway Formation of North Canterbury, is more complete than any found previously in New Zealand. The specimen, a young adult, comprises posterior fragments of the skull, almost the entire vertebral column, fragments of the major bones of both pectoral and pelvic girdles, and portions of all four limbs. Comparison with the partial pelvic girdle and hind paddle that constitute the lectotype of Mauisaurus haasti Hector, 1874 (including the femur, diagnostic of the species), indicates that the new specimen belongs to that species, permitting a more complete description and diagnosis. The species is characterized by an estimated 86 presacral vertebrae, at least 66 of which are cervicals, other than the atlas and axis. The coracoids possess a pronounced, blunt, ventral process, and a broad, rounded, transverse ridge on their dorsal surface. In large adults the medial profile of the coracoid becomes markedly sigmoidal. The adult femur has a large hemispherical capitulum; the humerus is relatively broad with an elliptical capitulum. In life, the animal would have been in excess of 8 m long. Comparisons with previously described elasmosaurs are difficult because of barely adequate published descriptions, but Mauisaurus haasti is distinguished particularly by postcranial characters that vary among Late Cretaceous elasmosaurs from both the Northern and Southern hemispheres. The only other established New Zealand elasmosaur, Tuarangisaurus keyesi Wiffen and Moiseley, 1986, cannot be directly compared with Mauisaurus haasti and must remain a separate taxon.

Intratendinous ossification is widespread in dinosaurs (including birds). Although intratendinous ossification in living birds is well understood, the physiological process of tendon metaplasia and associated histological variability in Dinosauria are not. Therefore, ossified tendons were histologically sampled across extinct dinosaurian clades. Tendons of living birds and alligators were also sampled. Despite various anatomical locations and large differences in body size, ossified tendons were found to possess uniform microstructure even in specimens that do not normally experience intratendinous ossification (such as Spinostropheus and Camarasaurus). The ossified tendons of non-avian dinosaurs are largely indistinguishable from skeletal bone with respect to microanatomical features. However, ossified tendons in birds lack periosteal bone and associated fibrolamellar structures associated with ornithischian dinosaur tendons. Variation in periosteal bone occurs along the length of individual tendons. Ossified tendons from marginocephalians are unique in that they have large quantities of anisotropic fibrolamellar bone, while those from pachycephalosaurids have radial vascularity.

Development and metaplasia of ossified tendons in two hadrosaurine dinosaurs (Maiasaura peeblesorum and Brachylophosaurus canadensis) are described by comparison with the known developmental processes of ossified tendons in turkeys (Meleagris gallopavo). Mineralized primary tendon tissue and replacement patterns suggest that ossified tendons in hadrosaurs grew initially in a manner similar to those in turkeys. That is, biomineralization begins with apatite deposition and is followed by resorption of mineralized primary tissue and subsequent bone formation. Earlier ontogenetic onset of tendon ossification and later offset among ossified tendons of hadrosaurs differentiates them from tendons of turkeys. In addition, an external fundamental system (EFS) in hadrosaurian tendons indicates that they grew radially beyond the original tendon boundary, a process unknown among avian tendons. Tendon histology indicates that hadrosaurian ossified tendons developed in step with the skeletal system and that ossification was not induced by biomechanical stresses.

A new specimen of the sauropod titanosaur Neuquensaurus australis, collected in the locality of Cinco Saltos (Patagonia, Argentina), provides an opportunity to improve our knowledge of the anatomy of this dinosaur. The elements represented in this specimen include a complete cervical vertebra, most of the dorsal vertebrae, fifteen caudal vertebrae, the complete sacrum articulated to both ilia, one ischium, two femora, one tibia articulated to the fibula and astragalus, and two osteoderms. Surprisingly, the sacrum is composed of seven vertebrae, the last of which, unfused to the other six, is apparently biconvex. A third femur and one tibia were found associated with this specimen; these are morphologically similar but stouter than those belonging to the former specimen.

An articulated skeleton of Messelastur gratulator Peters, 1994, from the middle Eocene of Messel in Germany is described. This species was hitherto known from two skulls with associated vertebrae only, and has been tentatively classified in the Accipitridae (hawks). The new specimen shows that M. gratulator closely resembles the Lower Eocene Tynskya eocaena Mayr, 2000a, which is known from an articulated skeleton from the North American Green River Formation and isolated bones from the London Clay in England. Both species, M. gratulator and T. eocaena, are assigned to the new taxon Messelasturidae. The new specimen exhibits previously unknown osteological details bearing on the phylogenetic position of the Messelasturidae, most notably the absence of an ossified supratendineal bridge on the distal tibiotarsus. Cladistic analysis of 110 characters supports sister-group relationship between Messelastur and Tynskya, and shows the Messelasturidae to be the sister taxon of owls (Strigiformes). The clade (Messelasturidae Strigiformes) is shown to be the sister group of the clade (Falconidae [falcons] Accipitridae). Among the known fossil raptorial birds, the Messelasturidae most substantially differ from the extant taxa. They provide a morphological link between Strigiformes and Falconiformes (diurnal birds of prey), and support the highly disputed falconiform affinities of owls in combining derived tibiotarsus and tarsometatarsus characters of owls with a more plesiomorphic, ‘falcon-’ or ‘hawk-like', skull morphology.

A new sphenodontid is described from the Middle Jurassic red beds in Huizachal Canyon, Tamaulipas, northern Mexico. The new taxon is characterized by the presence of two fang-like acrodont teeth at the anterior end of the lower jaw similar to those of the upper Jurassic sphenodontian Theretairus antiquus from the Morrison Formation. However, the new sphenodontian has a single well established groove on the anteromedial surface of each fang, here interpreted as a venom conducting groove convergent with those of opisthoglyphous colubrids and helodermatid lizards. The presence of a complex venom apparatus is supported by the reduction of the postcoronoid portion of the lower jaw to only 30% of the total jaw length and the anterior displacement of the jaw articulation by an unusual, medially inflected condyle. The shortening of the postcoronoid portion of the jaw reduces the estimated jaw moment-arm, trading bite strength for speed; simultaneously the mouth gape is increased by an additional 100% compared to other sphenodontians. Both modifications are necessary in an akinetic skull to facilitate venom injection to the victims. The phylogenetic relationships of the new sphenodontian are uncertain although the presence of propalinal jaw action and caniniform teeth suggests close relationship with Theretairus, Cynosphenodon, and Sphenodon. The transformation series leading to the presence of one or two caniniform teeth can be reconstructed either as an independent origin for both conditions or as an ordered transformation from one to two caniniform teeth. The new sphenodontian adds to the growing list of unusual forms and corroborates the view that Rhynchocephalia were once a very diverse group.

Haborophocoena toyoshimai (family Phocoenidae), from the early Pliocene Mochikubetsu Formation in northwestern Hokkaido, Japan, is a new genus and species of porpoise. The holotype is an incomplete skull, tympanoperiotic, mandible, and several teeth. Its features include: a robust and asymmetrical skull; a premaxilla with a less atrophied posterior extremity; a low but wide premaxillary eminence; a conspicuous knob-like frontal boss; narrow palatines posteriorly separating the pterygoids; a thin lateral lamina of the palatine that extends posteriorly; well-excavated air sinus fossae on the basicranium; a relatively small temporal fossa; an abruptly sloping supraoccipital shield; a periotic with massive anterior process; and tiny teeth with blunt tips. Some features of living phocoenids may be paedomorphic; examples include the relatively short rostrum, the rounded cranium, and the small body size. “Precocious” reproduction and a short interval of the reproductive cycle, compared to other delphinoid dolphins, suggest that paedomorphic characters of living phocoenids are progenetic. Progenetic evolution possibly occurred in harsh environments caused by glacial oscillations of the Pleistocene; molecular divergence times for porpoises are compatible with this idea.

A new species of Hippopotamidae based on abundant and well-preserved remains was discovered in the late Miocene levels of the Toros-Ménalla fossiliferous area in the Djurab desert, Chad, central Africa. This hippopotamid is contemporaneous with Sahelanthropus tchadensis, a hominid from the same area, with an age of ca. 7.0 Ma. Hexaprotodon garyam sp. nov. is a large species with a robust, high mandibular symphysis. This feature is unknown in the Miocene East African hippos found at Lothagam, Kenya, but characterizes the Asian Hexaprotodon. This discovery enhances the heterogeneous character of the paraphyletic Hexaprotodon and indicates that the Hippopotamidae were a major component of the late Miocene environments in Central Africa as well as in East Africa.

The diverse fauna from Salla, western Bolivia, represents a rare glimpse into the evolutionary history of Tertiary South American mammals outside of Patagonia (Argentina). The Hegetotheriidae (Notoungulata) from the Deseadan of Salla are composed of two taxa, a new genus and species and a species of Prohegetotherium. Sallatherium altiplanense gen. et sp. nov., differs from Prohegetotherium by its very long, thin nasals; more medially placed labial groove on upper cheek teeth; more reduced I2-I3-C and i3-c separated by diastemata; and much narrower symphysis. The smaller, more common hegetothere from Salla is identified as Prohegetotherium schiaffinoi; the abundant new material from Bolivia permits a better characterization of this otherwise poorly known species from Uruguay and Argentina (Corrientes and Entre Ríos provinces). The Divisaderan Ethegotherium carettei from Argentina is regarded as a junior synonym of P. schiaffinoi, extending the chronologic range of the genus into the early Oligocene. A revised diagnosis of the type species of Prohegetotherium, P. sculptum, is provided based on new material. This species is known exclusively from Argentina.

All known Pleistocene fossils of manatees from North America are conspecific with the living West Indian manatee, Trichechus manatus. However, those of late Pleistocene (late Rancholabrean) age differ from all modern manatees, and are here assigned to a new subspecies, T. m. bakerorum. In contrast, early Pleistocene manatees from the late early Irvingtonian Leisey Shell Pit Local Fauna, Florida, do not clearly differ from modern West Indian manatees and are here referred to T. manatus, subspecies indeterminate. I hypothesize that warm intervals during the Quaternary allowed manatees from the Caribbean (represented today by the Antillean subspecies, T. m. manatus) to disperse northward into the United States. Ecological barriers (cool winters on the northern Gulf of Mexico coast, deep water and strong currents in the Straits of Florida) then impeded genetic contact with Caribbean populations and permitted evolution of endemic North American forms (T. m. bakerorum and the living Florida manatee, T. m. latirostris). Conditions much warmer than today might have eliminated the northern Gulf Coast barrier and allowed gene flow from the Caribbean to swamp such endemic gene pools. Return of glacial conditions reversed these northward range extensions and brought about periodic extinction of manatees in North America. This mechanism might explain the morphological uniqueness of the late Rancholabrean manatees, as well as the fact that early Pleistocene manatees from Florida are more similar to modern T. m. manatus than the late Pleistocene ones are. This model also helps explain phylogeographic patterns detected in mitochondrial DNA data from living manatees.

Deciduous premolars of Mammut americanum have received relatively little study, and previous work was based on small sample sizes. We present morphologic descriptions and quantitative data for a sample of over 135 deciduous premolars of M. americanum from Florida. Most second and third deciduous premolars are bilophodont, although a few anomalous teeth deviate from this pattern to a varying degree. Although the premolars are morphologically similar to the adult molars in many respects, differences in development of cingula, orientation of lophs and lophids, and relative strengths of enamel crests are observed. Distal cingula and stylar cusps are the most variable portions of the crown. Crown length increases distally along the tooth row, with no observed overlap in length between adjacent teeth.