A new birkeniid anaspid, Cowielepis ritchiei gen. et sp. nov., from the mid Silurian Cowie Harbour fish bed in Scotland is described on the basis of three specimens. Although sharing characters with various well-known anaspids, it possesses a unique combination of features that justifies the establishment of a new genus. Cowielepis is characterized by a single row of dorsolateral scales and a distinctive skull roof pattern with a large pineal plate and elongated posterior plates. The presence of paired ventrolateral fins in C. ritchiei supports previous suggestions that all anaspids possess such fins, but leaves open the question of homology with the gnathostome pectoral fin.

Denticles and denticulate platelets belonging to internal structures of Phlebolepis elegans Pander, along with two new types of scales, are described for the first time. Large fragments taken from seven articulated specimens of P. elegans were dissolved in acetic acid. The denticles were picked from the resulting residues where they were found adhering to the visceral surfaces of scales in samples taken from the anterior part of the body. The overall shapes of the tiny denticles vary from rhombic to elongate, and the sculpture on their surface consists of longitudinal ridges of different lengths and/or tubercles. Denticles are also covered with an ultrasculpture of longitudinal striations. The shape of each denticle varies depending on where it was situated in the body. Rhombic or roundish denticles were found together with rostral and short cephalo-pectoral scales, the latter often pierced by pore canals of the lateral line system; strongly elongate denticles were associated with long lateral scales. These newly described denticles covered the buccopharyngo-branchial region of P. elegans. Denticulate platelets also came from the branchial region. Two sets of scales in a slightly crescent-shaped arrangement are bordered on one side by very narrow and high scales. These crescent-shaped sets bordered openings, which are here interpreted as branchial openings. The openings were situated between long lateral scales, and each successive opening was placed slightly ventral to its more anterior neighbor. These internal denticles reinforce the idea that such structures are general features of thelodonts, and not specializations of restricted groups of thelodonts.

Ilemoraspis kirkinskayae is a poorly known genus of Osteostraci (stem-gnathostome) yet is one of the most distinct in terms of its anatomy and biogeography. It is paleobiogeographically isolated from all but one other genus of Osteostraci on the Altaid microcontinents and is one of the few genera to survive into the Middle Devonian. Discovery of a new locality in Khakassia, Russia, has yielded a number of exceptionally well-preserved specimens of the genus and subsequently a wealth of new anatomical information. A new reconstruction of Ilemoraspis is provided, including postcranial anatomy and a sensory line extending onto the trunk. The latter is a novel observation for the Osteostraci and allows the proposal of a scenario for the evolution of trunk lateral lines. New anatomical data for I. kirkinskayae allow testing of established hypotheses on its affinity. Our analyses yield two equally parsimonious solutions that appear unlikely on the basis of comparative anatomy or paleobiogeographic grounds, respectively. This situation is likely to be a consequence of the sporadic sampling of osteostracans in central Asia.

A recent analysis of the vascularization of the pectoral fin in antiarchs indicated that they resembled jawless osteostracans rather than other jawed vertebrates, thereby challenging the monophyly of the class Placodermi. Examination of the evidence proposed to support this new hypothesis shows misinterpretation of well-established morphology in a range of antiarchs, with incorrect homologies being applied to conclude that the subclavian artery and vein originated in the back of the branchial chamber. The interpretation is rejected and evidence is summarized showing that pectoral fin vascularization in antiarchs conforms with that of other jawed fishes. The position of the antiarchs as a major subgroup of the placoderm fishes is confirmed, with four antiarch characters (external endolymphatic openings; palatoquadrate-suborbital plate complex; Meckel's cartilage-infragnathal connection; extensive postorbital endocranial processes) providing additional support for placoderm monophyly.

The tetrapodomorph fish Spodichthys buetleri from the Upper Devonian of East Greenland is redescribed from computed tomography scans of material originally studied by Erik Jarvik. A wealth of new anatomical data was revealed by scanning the nearly perfectly three-dimensional specimens, including detailed information on the shape of the brain cavity and the internal structure of the lower jaws. Spodichthys displays an interesting mix of generalized “osteolepidid,” or primitive tetrapodomorph, and tristichopterid features. Derived characters shared by Spodichthys, tristichopterids and (Panderichthys Tetrapoda) include the loss of cosmine, a small kite-shaped parasymphysial plate, and a long commissural lamina of the entopterygoid. The presence of an extratemporal lateral to the tabular and a single fang position on the posterior coronoid and ectopterygoid are examples of basal tetrapodomorph characters retained in Spodichthys. Spodichthys is unique in having coronoid fangs positioned lateral to the corresponding replacement pit rather than having an anterior-posterior alternation between developed fang and replacement pit, which is the normal tetrapodomorph condition. Jarvik's original conclusion that Spodichthys is closely related to the tristichopterids is confirmed by a phylogenetic analysis, which places Spodichthys as the sister taxon of the Tristichopteridae.

A new temnospondyl, Kryostega collinsoni, gen. et sp. nov., is described on the basis of a large snout fragment from the Triassic upper Fremouw Formation of Antarctica. K. collinsoni is characterized by greatly enlarged teeth of the transvomerine and parachoanal tooth rows, a reduced transvomerine tooth row, as well as a distinct process on the palatal surface of the premaxilla. Although key palatal and tabular features are not preserved, the shape and position of the external naris, choana, and anterior palatal vacuity suggest that K. collinsoni may be allied to the Heylerosauridae or basal Mastodonsauridae. The discovery of K. collinsoni in the upper Fremouw is surprising, given that Triassic vertebrates from Antarctica are typically considered a subset of coeval taxa from the Karoo Basin of South Africa. Based on its unique occurrence in Antarctica, K. collinsoni suggests that high latitude Triassic tetrapods had a more restricted geographic distribution than previously considered. Biostratigraphically, the fauna of the upper Fremouw Formation is best correlated with the Cynognathus Assemblage Zone of South Africa's Beaufort Group, although the lack of species–level identifications for many of the Antarctic fossils precludes a more refined correlation. A review of the Triassic fossil record identifies several tetrapods that make their first appearance in the Fremouw, with a later appearance in the Karoo Basin, suggesting that the high latitude regions of Gondwana might have served as an important area for speciation.

The taxonomic identity of two well-preserved polycotylid plesiosaur skeletons from the Pierre Shale of far northern Wyoming and southern South Dakota has been controversial since their discovery. Originally referred to Dolichorhynchops osborni, the material was almost immediately christened Trinacromerum bonneri Adams 1997; more recently the material has been referred to Polycotylus. Recent preparation of the well-preserved skull of one specimen permits detailed examination of the cranial morphology of this animal for the first time, and allows for its inclusion in a cladistic analysis of the Polycotylidae. This analysis reveals a stable sister-taxon relationship with Dolichorhynchops osborni. However, the taxon possesses a bewildering mosaic of character states, superficially resembling Polycotylus in overall size and tooth morphology and Trinacromerum in details of the palate and lower jaw, while sharing several critical synapomorphies with Dolichorhynchops osborni. This wide-ranging homoplasy among characters previously diagnostic among polycotylid genera challenges the alpha taxonomy of forms from the western interior seaway. The conservative taxonomic course of referring the species T. bonneri to Dolichorhynchops is followed here, but a species-level review is necessary. Lastly, material described here reveals important new information concerning the polycotylid orbital region and lower jaw, allowing confident reconstructions of these controversial regions for the first time.

A new specimen of the parareptile Colobomycter pholeter, from the Lower Permian Dolese Brothers Quarry near Fort Sill, Oklahoma, preserves previously unknown portions of the skull, including the premaxilla, elements of the palate, and the sphenethmoid. The premaxilla houses two teeth, of which the first is caniniform in size. The pattern and the morphology of the upper dentition indicates that C. pholeter was a small faunivore. Fortuitous damage to the dentition reveals that the large marginal teeth are polyplocodont, the simplest kind of folded teeth. The folding may have strengthened the crowns of teeth, which were otherwise relatively thin-walled in C. pholeter. Considering its small size, C. pholeter was either an insectivore that specialized on prey with hard exoskeletons, or an insectivore that was facultatively carnivorous, capable of taking other small vertebrates as opportunities arose. Folded teeth appear not to be a rare phenomenon among parareptiles, but given the lack of detailed descriptions of the dentition for many parareptiles, the evolutionary history of polyplocodont teeth in this group requires further investigation. Phylogenetic analysis of an augmented data matrix from the literature supports the hypothesis of a sister-group relationship between C. pholeter and the lanthanosuchoid Acleistorhinus pteroticus.

The study of the so-called vertebral ‘pachyostosis’ of Carentonosaurus mineaui, a plesiopedal mosasauroid sensu Bell & Polcyn from the Cenomanian (Late Cretaceous) of Charente-Maritime (Western France), has revealed that it actually corresponds to pachyosteosclerosis resulting from the combination of cortical hyperplasy with bone compaction due to an inhibition of chondroclastic and osteoclastic activities. This characteristic also occurs in other Cretaceous squamates such as Pachyvaranus crassispondylus and Simoliophis rochebrunei but it is absent in extant squamates. On the contrary, vertebrae of the latter display a very strong porosity due to intense bone remodelling during growth. The phylogenetic significance of pachyosteosclerosis in squamates is thus discussed. The peculiar structure of the vertebrae of Carentonosaurus may be regarded as the result of a heterochronic process, more specifically neoteny. Its association with an adaptation to shallow marine environment is consistent with the inferred ecology of C. mineaui. Moreover, the histological features of the periosteal bone of Carentonosaurus vertebrae provide information about its growth pattern (asymmetry, rate, cyclicity) which may be compared to the ones of Pachyvaranus and Simoliophis.

A small aetosaur skeleton collected in 1939 from the Tecovas Formation of Texas and assigned to Desmatosuchus is reassigned to a new taxon, Sierritasuchus macalpini. Phylogenetic analysis suggests that Sierritasuchus is a member of the Desmatosuchinae. It can be distinguished from other desmatosuchines by two autapomorphies: (1) recurved spines on the lateral plates that are triangular in cross-section with a sharply ridged anterior edge; and (2) the presence of a sharp, ventrally oriented ridge on the posterior faces of the dorsal eminences of the paramedian plates, as well as a unique combination of characters including the presence of an anterior bar on the paramedian and lateral plates, a random pattern of ornamentation on the paramedian plates, and a dorsal eminence that contacts the posterior plate margin of the paramedian plates. Histological study of the holotypic plates in combination with comparison to a growth series in Typothorax, and size-independent growth indicators such as neurocentral suture closure suggests that the specimen is neither a young juvenile nor a fully-grown adult. The recognition of morphologically distinct specimens such as the holotype and referred material of Sierritasuchus demonstrates that past practices of assigning aetosaur specimens to known taxa based on superficial resemblance has masked diversity in this clade. Voucher specimens for biochronologic and biogeographic analyses should be carefully investigated before being used for such studies.

Heterodontosaurids are an enigmatic group of primitive ornithischian dinosaurs best known from the Early Jurassic of southern Africa. Because fossil material is rare and often poorly preserved, the taxonomy, systematics, and palaeobiology of this clade are controversial. Here we describe a new partial skull of a juvenile Heterodontosaurus tucki from the 'Stormberg' of South Africa. This skull provides new information on the cranial anatomy of this taxon as well as insights into cranial ontogeny, sexual dimorphism and tooth replacement in heterodontosaurids. Few ontogenetic changes in dental morphology occur in Heterodontosaurus, supporting previous suggestions that tooth characters are informative for species-level taxonomy in heterodontosaurids. Furthermore, the presence of well-developed caniniform teeth in the juvenile specimen does not support the hypothesis that these represent secondary sexual characteristics in heterodontosaurids. Computed tomography reveals that replacement teeth are absent in both juvenile and adult specimens of Heterodontosaurus; however, the difference in the absolute size of the teeth between the juvenile and adult specimens demonstrates that replacement must have occurred during ontogeny.

The new sauropod dinosaur Tastavinsaurus sanzi, gen. et sp. nov., from the early Aptian of Spain is described. The holotype is a partially articulated skeleton of an adult individual recovered from the Arsis-1 site in Peñarroya de Tastavins (Teruel) at the base of the marine Xert Formation. It is one of the most complete and best-preserved sauropod dinosaur skeletons from the European Early Cretaceous. The fossil remains comprise the three caudalmost thoracic vertebrae, part of a fourth, nine thoracic rib fragments, sacrum, 25 caudal vertebrae, 21 chevrons, both ilia, pubes, ischia and femora, right tibia, right fibula, six metatarsals, and seven pedal phalanges (including four unguals). The new taxon is defined by 19 autapomorphies. In our cladistic analysis, Tastavinsaurus is the sister-taxon of the North American Venenosaurus within Titanosauriformes, which includes the Brachiosauridae, Somphospondyli, and Titanosauria. The new taxon provides new information about the diversity of non-brachiosaurid titanosauriforms during the Early Cretaceous in Europe and paleobiogeographic relationships between Europe and North America.

A partial postcranial skeleton from the Late Jurassic (Tithonian) of Dorset, England represents a new species of the theropod dinosaur Stokesosaurus, Stokesosaurus langhami. S. langhami is a member of Tyrannosauroidea, showing a distinct median vertical ridge on the lateral surface of the ilium, a prominent shelf medial to the preacetabular notch, a pronounced ischial tubercle, and a tibia that is elongate relative to the femur. One of only two definitive Jurassic tyrannosauroids known from more than isolated elements, it is the largest Jurassic tyrannosauroid reported to date and provides additional evidence for the presence of relatively small- or medium-sized basal tyrannosauroids in Asia, North America, and Europe during the Late Jurassic. The occurrence of Stokesosaurus in the Tithonian of the UK and USA and the absence of tyrannosauroids in contemporaneous west African faunas supports the hypothesis of a paleobiogeographic link during the Late Jurassic between North America and Europe, to the exclusion of Africa.

New specimens of Lithoptila abdounensis (Prophaethontidae) including long bones and fragments of mandibulae are described from the Upper Paleocene and Lower Eocene of the Ouled Abdoun Basin, Morocco. Elongated and slender wing bones suggest that this bird was an offshore or pelagic feeder capable of efficient flight. Lithoptila approximates Prophaethon in size but differs from the latter taxon in various features of the mandibula, coracoideum and femur. The anatomy and size of Lithoptila closely match those of Zhylgaia aestiflua, a putative shorebird (Charadriiformes) from the Upper Paleocene of Kazakhstan, known from two partial humeri. Consequently, we assign Zhylgaia aestiflua to the Prophaethontidae. The three species of Prophaethontidae inhabited tropical seas and most likely had comparable ecological niches.

The sternum of a very large bony-toothed bird (Pelagornithidae) from the Miocene of Portugal is described. The three-dimensionally preserved specimen is one of the largest sterna of a volant bird known to date, and more complete than the only other pelagornithid sternum reported so far. It is tentatively assigned to Pelagornis miocaenus Lartet, 1857, which is the only bony-toothed bird known from the Miocene of Europe. The specimen shows several unique features, including the presence of a marked cranial projection of the carina sterni, which probably abutted the extremitas sternalis of the furcula, and a large, steep-walled opening in the cranial portion of the facies visceralis. The corpus sterni further has a highly unusual shape in that it is very deep, with a strongly vaulted facies visceralis. It is likely that these characteristics are due to anatomical constraints imposed by the very large size of pelagornithids, which may have reached a wingspan of up to 6 m and probably were incapable of sustained flapping flight.

An enigmatic dicynodont specimen from Tweefontein in Graaff-Reinet, South Africa, represents a new species of the Middle to Late Permian genus Emydops, E. oweni. Taxonomic revision of the genus reveals that, of the thirteen previously described species, only E. arctatus is valid. The holotype of E. oweni, SAM-PK-3721 is unusual in that it bears two tusks on each side of the skull, a symmetrically developed double-tusked condition being a very rare if not unique case in the dicynodont fossil record. The possible pathological causes for this occurrence are discussed and the production of the supernumerary teeth by mutation is considered to be the most likely explanation. Phylogenetic analysis supports the sister-taxon relationship of the two species of Emydops and their position at the base of Emydopidae. Emydops oweni shares a number of derived characters with E. arctatus, including its small size, wide temporal region, prominent lateral dentary shelf, embayment on the medial surface of the palatal rim, and squared-off profile of occiput. In addition to its aberrant dentition, SAM-PK-3721 can be distinguished from the type species by a number of autapomorphies, including the absence of the small maxillary foramen lateral to the postcaniniform keel, the presence of a distinct ventrolaterally projecting pterygoid flange, and the diagnostic shape of the lateral dentary shelf. The identification of two additional tuskless specimens referable to the new species excludes the possibility that the autapomorphic characters are associated with the double-tusked condition, allowing us to conclude that E. oweni has both tusked and tuskless morphs.

Dicynodont therapsids were cosmopolitan members of Middle and Late Permian terrestrial ecosystems. Despite occurring in nearly all places where tetrapod fossils of these ages are found, it is unclear whether any individual dicynodont species ever achieved a Pangaean distribution, with populations located in both Gondwana and Laurasia. Diictodon feliceps (Owen, 1876) is perhaps the best candidate for a species with such a broad distribution, but this depends on whether D. tienshanensis (Sun, 1973) from the Junggur Basin of China is a valid species. We use qualitative morphological characters, as well as linear measurement- and landmark-based morphometric techniques, to demonstrate that IVPP V.3260 (the type and only known specimen of D. tienshanensis) falls well within the range of variation displayed by D. feliceps, implying that D. tienshanensis is not a valid species. The occurrence of D. feliceps in China poses a biogeographic puzzle, since this species is otherwise known only from southern Africa. We predict that D. feliceps will be discovered in areas between southern Africa and China. However, if its absence persists in the face of continued exploration and collecting efforts, it may imply that a dispersal route and/or intervening populations of D. feliceps existed in areas in which an Upper Permian terrestrial fossil record was not preserved. Finally, if dicynodonts were adapted to exploiting components of the Gondwanan flora, the presence of D. feliceps in Gondwana and Laurasia indicates that such trophic interactions were not an insurmountable barrier to their dispersal.

Isolated teeth representing several taxa of metatherian mammals were recovered from NMMNH locality L-4005 in the Naashoibito Member, Kirtland Formation, San Juan Basin, northwestern New Mexico. These include fragments of upper and lower molars and a fragmentary premolar that are referred to indeterminate “pediomyids,” an isolated p2 or p3 that is referred to an indeterminate peradectid, and two lower molars, an m1 or m2 and an m4 that are referable to the hatcheriforme metatherian Glasbius cf. G. intricatus. Two upper molar fragments are also tentatively referred to Glasbius. These taxa are part of the Alamo Wash local fauna. Glasbius has been proposed as a potential first appearance datum for the Lancian North American Land Mammal ‘age’ (NALMA). The presence of both Glasbius and the multituberculate Essonodon within the Naashoibito Member support an age correlative with other formations producing Lancian faunas. A Lancian age for the Naashoibito Member suggests that there is a significant disconformity between the top of the late Campanian De-na-zin Member, which is constrained by radiometric dates to be about 73 Ma, and the base of the Naashoibito Member. Terrestrial faunas of Lancian age show differences that have been attributed to provinciality. The widespread distribution of mammalian index taxa indicates some degree of faunal homogeneity during this interval, but the refined stratigraphic correlation of the Alamo Wash local fauna allows us to recognize other taxa as geographically restricted, as opposed to asynchronous.

Utilizing the occurrence of plesiadapid mammals, we recognize both Tiffanian and Clarkforkian ages in the Fort Union Formation of the Piceance Creek Basin of Colorado. Five species of plesiadapids are described from eighteen fossil localities. The presence of Nannodectes gazini, Plesiadapis fodinatus and a new species Chiromyoides gigas indicate that at most eleven of the reported fossil localities are Tiffanian in age. The majority of the fossil specimens come from UCM locality 92177 (USGSD-2001) located 35.8 meters above the base of the Fort Union Formation, which we place in the Ti5 lineage zone. The occurrence of Plesiadapis dubius and Chiromyoides caesor in the Plateau Valley area suggests a younger Clarkforkian age for these stratigraphically higher localities. We are the first to recognize Tiffanian aged fossils in the Piceance Creek Basin, extending the mammalian record back to more than 58 million years ago.

A new genus, Vectipithex, is erected in the subfamily Microchoerinae, family Omomyidae, for four species, of which one, the type species is new: V. smithorum sp. nov. ‘Protoadapis’ ulmensis is referred to Vectipithex and transferred from the family Adapidae. Two species of Nannopithex, ‘N.’ quaylei and ‘N.’ raabi are also referred to the new genus. Vectipithex has a geographic distribution in north and west Europe and a stratigraphic distribution from the early Middle Eocene (Lutetian) to latest Eocene (late Priabonian). Cladistic analysis shows that Vectipithex is sister group to a clade composed of Microchoerus, Necrolemur, Nannopithex filholi, and ‘N.’ zuccolae and that poorly known ‘N.’ humilidens is sister group to those two. The Microchoerinae are shown to have undergone a phase of rapid diversification in the first few million years of the Eocene.

The Arvicolinae from the latest Ruscinian and early Villanyian sites of the section of Tollo de Chiclana (Southern Spain) are re-examined in the light of new material and exhaustive comparisons with other European populations. The uppermost Ruscinian population from TCH-1B, previously assigned to Mimomys stehlini, is now ascribed to M. hassiacus, cited for the first time from southern Spain. The populations from the lower Villanyian localities of TCH-3 and 13, assigned to M. minor, are considered to belong to M. stehlini. In addition, the material from the uppermost Ruscinian karstic level of Mo1-A, assigned to “Mimomys” occitanus is ascribed to M. hassiacus. The presence of different species of Arvicolinae is key for delimiting the Ruscinian–Villanyian boundary in the continental deposits of southern Spain and correlating them with European biochronological schemes. In this paper we discuss the problems associated with specific identifications of upper Ruscinian and lower Villanyian arvicolines from Spain, pointing out the invalidity of many citations, and demonstrating the need for an extensive revision of these faunas.

The first castorid remains from the area of els Hostalets de Pierola (l'Anoia, Catalonia, Spain), in the Vallès-Penedès Basin, are described in this article. These fossil remains from Abocador de Can Mata (ACM), including a nearly complete hemimandible, two maxillary fragments, and several isolated teeth from locality C4-C2 (Late Aragonian, MN7 8), as well as an almost complete femur from the similarly-aged locality C3-Ak, are attributed to the genus Chalicomys (=Palaeomys). Taxonomic and nomenclatural issues regarding this genus are discussed. An emended diagnosis of this genus is provided, and a new species, Chalicomys batalleri sp. nov., is described on the basis of the ACM/C4-C2 specimens. The femur from ACM/C3-Ak is also tentatively included within the hypodigm of the newly erected species. Paleobiological inferences on the locomotor repertoire of Chalicomys are made on the basis of femoral anatomy. It is concluded that, like living Castor, these extinct beavers were efficient swimmers, highly committed to aquatic locomotion, which propelled mainly by means of hind feet paddling. The presence of an extinct beaver with Castor-like aquatic adaptations in this area, together with the sedimentological evidence, suggests more humid conditions than previously thought, at least for a restricted to a short time interval, given the rarity of castorid remains elsewhere in the ACM stratigraphic series.

The study of an isolated skull discovered in early late Pliocene (Piacenzian) sands at Antwerp, northern Belgium, southern margin of the North Sea Basin, leads to the description of a new genus and species of porpoise (Odontoceti, Phocoenidae), Septemtriocetus bosselaersi. This is the first clear record of a fossil phocoenid from the North Atlantic. With a cranium slightly larger than the largest Recent phocoenid (Dall's porpoise Phocoenoides dalli), the new species is characterized by a constriction of the premaxilla anterior to the rostrum base, a longitudinally elongated frontal boss, and a large temporal fossa. A cladistic analysis of fossil and Recent phocoenids confirms the monophyly of the Recent phocoenid subgroup and suggests a sister-group relationship between Septemtriocetus and the Japanese Pliocene phocoenid Haborophocoena. The geographic pattern of fossil and Recent phocoenids mainly in the Pacific Ocean, combined with phocoenid phylogenetic relationships, suggests an initial early to early late Pliocene north dispersal via the Arctic Ocean to the North Atlantic for the lineage of Septemtriocetus. A subsequent late Pliocene-Pleistocene dispersal event accounts for the Recent distribution of the harbour porpoise Phocoena phocoena in the North Atlantic.

A new species of moschid, Micromeryx azanzae sp. nov., is described on the basis of new fossil material from Toril-3 localities (upper Aragonian; local zone G3, MN 7/8, Zaragoza province, Spain). The fossil localities of Toril-3A and 3B have yielded exceptional material of this taxon, including the first ever described Micromeryx skull remains, dramatically improving the knowledge of Micromeryx morphology; previously unknown regions of the skeleton described here include the tympanohyal complex and most of the postcranial skeleton, both of which will be of great importance in reconstructing the sequence of character state changes within the Moschidae. Evidence for metric sexual dimorphism in M. azanzae is also discussed. Micromeryx azanzae is the best-represented species of the Moschidae in the Spanish fossil record, not only because of the quality and quantity of the fossil material but also because the species appears at nine fossil sites and three sedimentary basins that span three million years (local zones F–H, MN 6 to early MN 9).

The paleoecology and palaeoethology of the Eurasian species of the extinct genus Cervalces are inferred by morpho-functional comparison with its living relative Alces alces. Most of the characters that differentiate A. alces from all other deer are shared by Cervalces: the peculiar morphology of the cheek teeth; the shape of the premaxillary tips; the long legs; the peculiar morphology of the femur; the extreme fusion of the tarsal elements; the peculiar articular surface of the third phalanx. The most important morpho-skeletal differences between the two genera are: the long nasal bones contiguous with the short premaxillary bones in Cervalces (whereas Alces has very short nasal bones not contiguous with the extremely long premaxillary bones); the stronger and more backward inclined ascending ramus of the mandible in Cervalces; the much wider span of antlers in Cervalces because of its longer beams; the different shape of the antler palmation; the stronger proximal ulna/radius connection in Cervalces. The close similarity between the morphological features of the dentition and postcranial skeleton of Alces and Cervalces suggests that they could have chewed the same kind of food and moved in the same way. However, their quite different facial skeleton and antler shape, should have played some ecological role, even if interpretation of such a role is difficult. Such wide antlers may possibly have served as display organs in open ground. Nevertheless, the common idea that Cervalces should have lived in more open environments than living moose is probably an oversimplification.