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Morphological changes in the ontogeny of sauro- pods are poorly known, making difficult to establish the sys- tematic affinities of very young individuals. New information on an almost complete juvenile sauropod (SMA 0009) with an estimated total length of about 2 m is here presented. The specimen was described as a diplodocid owing to the pres- ence of some putative synapomorphies of this group. How- ever, recent further preparation revealed the absence of diplodocid characters and the presence of macronarian derived characters. To test the affinities of this specimen, a phylogenetic analysis was conducted. The strict consensus tree recovers the specimen as a basal titanosauriform, in an unresolved relation with Brachiosaurus and Giraffatitan. Nev- ertheless, a brachiosaurid assignment is here suggested in base of the widely accepted monophyly of this group (only recovered when SMA 0009 is placed within this group). Although the existence of a new taxon cannot be completely ruled out, the combination of derived and plesiomorphic characters in the specimen suggests its assignment to Bra- chiosaurus. Sixteen extra steps are needed to place this speci- men within Diplodocidae. The high cost to place this specimen within this group is owing to the fact that several diplodocid characters are absent in SMA 0009, such as the absence of divided centroprezygapophyseal lamina in cervical vertebrae, procoelous anterior caudal centra, composed lat- eral lamina in anterior caudal vertebrae, elongated middle caudal vertebrae, short cervical ribs and caudolateral projec- tion of distal condyle of metatarsal I. Finally, the systematic position reveals few major ontogenetic transformations. These affect the pneumatic structures (e.g. change from sim- ple pleurocoels in the cervical vertebrae to complex pleuroco- els and the development of lateral excavations in the dorsal vertebrae) but also include unrecorded transformations of the neural spine (e.g. the development of the spinodiapophy- seal lamina, the widening of the neural spines in the dorsal vertebrae) and allometric growth in some limb bones.

The Cretaceous dinosaur fauna of Indo-Pakistan has remained poorly understood because of a lack of asso- ciated and articulated remains, proliferation of named spe- cies, and an incomplete understanding of the dinosaur clades present (e.g. abelisaurid theropods; titanosaur sauro- pods). Continued work on existing collections, and new discoveries of dinosaur material from India, Pakistan and elsewhere in Gondwana, has begun to resolve the composi- tion and affinities of Indo-Pakistani dinosaurs. Here, we provide archival evidence that documents associations between postcranial remains of a sauropod collected from Chhota Simla, India by C. A. Matley in the 1930s and later described as 'Titanosaurus sp.' This partial skeleton, which represents only the fifth such documented association from Indo-Pakistan, is referable to Jainosaurus cf. septentrionalis and provides a fuller understanding of its anatomy and phylogenetic affinities.

The sauropod dinosaur, Barapasaurus tagorei, is known from the Early Jurassic Kota Formation (Sinemurian to Pliensbachian) of India. The taxon is represented by c. 300 bones that were found associated with large fossilized tree trunks and were collected from the interface of sandstone and mudstone units covering an area of c. 276 m2. The collection includes one partial skeleton; most of the remainder of the bones were disarticulated, disassociated and dispersed, but taphonomic analysis permits recognition of associated elements comprising several individuals. Skeletal anatomy of Barapasaurus includes several teeth, vertebrae from the caudal cervicals rearward to the terminal caudals, and most elements of the appendicular skeleton. Barapasaurus is characterized by spoon-shaped teeth with bulbous bases and grooves on the anterolabial and posterolingual sides of the crown, coarse tubercles on the carina, acamerate cranial and dorsal vertebrae, lateral laminae of the middle and caudal dorsal neural spines composed of spinodiapophyseal and spinopostzygapophyseal laminae, neural canal of the mid-dorsal vertebrae opens dorsally through a narrow slit into a large cavity and sacrum with four co-ossified vertebrae. Phylogenetic analysis reveals that Barapasaurus is basal in comparison with Vulcanodon and is removed from Eusauropoda.

The sauropod dinosaur ‘Bothriospondylus’, originally named on the basis of Late Jurassic remains from England, is demonstrated to be invalid, and the characters used to diagnose it are shown to be obsolescent features which are widespread throughout Sauropoda. Material referred to this genus spans a temporal range from the Middle Jurassic until the early Late Cretaceous and has been described from five different countries, across three continents. These remains represent a wide array of sauropod groups, comprising non-neosauropod eusauropods, a macronarian, titanosauriforms (including at least one definite brachiosaurid) and a rebbachisaurid. The type material of the Middle Jurassic ‘B. madagascariensis’ represents a derived non-neosauropod eusauropod and possesses two potential autapomorphies. However, as a result of the fragmentary nature of the material and the uncertainty surrounding its association, a new taxon is not erected. Of the numerous specimens referred to ‘Bothriospondylus’, however, several remains are considered diagnostic: Ornithopsis hulkei (Early Cretaceous, UK), Lapparentosaurus madagascariensis (Middle Jurassic, Madagascar) and Nopcsaspondylus alarconensis (early Late Cretaceous, Argentina). At least three types of sauropod were present in the Bathonian (Middle Jurassic) of north-west Madagascar, with a basal eusauropod (Archaeodontosaurus), a more derived eusauropod (‘B. madagascariensis’) and a titanosauriform (Lapparentosaurus) all approximately contemporaneous. Palaeocontinental reconstructions suggest that Middle Jurassic Madagascan sauropods would still have been capable of global biotic interchange, and this is perhaps reflected in their diverse assemblage. Re-evaluation of these Malagasy forms has shed new light on this important time period in sauropod evolution.

An isolated anterior caudal vertebra from the Qingshan (= Ch'ing shan) Formation (Early Cretaceous) of Shandong Province, China, is redescribed and shown to be an advanced diplodocid sauropod. This specimen possesses several derived character states that are typically observed in advanced diplodocoids or diplodocids, including the following: a mildly procoelous centrum; a deep pit-like pneumatic fossa immediately below the caudal rib; wing- or fan-shaped caudal ribs; and complex lamination of the neural spine. The neural spine is apomorphically short and the centrum is short relative to its height compared to those of other diplodocids, which, when coupled with the specimen’s unique geographical location and stratigraphical age, suggests that it probably represents a new taxon. This caudal vertebra provides the first convincing evidence that diplodocids were present in Asia, perhaps as a result of the dispersal of neosauropod lineages from Europe and/or North America during the Early Cretaceous. The discovery of a member of the Diplodocidae in the Early Cretaceous also indicates that this clade did not become extinct at the Jurassic/Cretaceous boundary as previously supposed.

Up to now, more than 40 dinosaur sites have been found in the latest Jurassic – earliest Cretaceous sedimentary outcrops (Villar del Arzobispo Formation) of Riodeva (Iberian Range, Spain). Those already excavated, as well as other findings, provide a large and diverse number of sauropod remains, suggesting a great diversity for this group in the Iberian Peninsula during this time. Vertebrae and ischial remains from Riodevan site RD-13 are assigned to Turiasaurus riodevensis (a species described in RD-10, Barrihonda site), which is part of the Turiasauria clade. This is the first time that a taxon is attributed to Turiasaurus genus out of its type site. A Neosauropod caudal vertebra from the RD-11 site has been classified as Diplodocinae indet., supporting the previous attribution on an ilion also found in Riodeva (CPT-1074) referring to the Diplodocidae clade. New remains from the RD-28, RD-41 and RD-43 sites, of the same age, among which there are caudal vertebrae, are assigned to Macronaria. New sauropod footprints from the Villar del Arzobispo Formation complete the extraordinary sauropod record coming to light in the area. The inclusion of other sauropods from different contemporaneous exposures in Teruel within the Turiasauria clade adds new evidence of a great diversity of sauropods in Iberia during the Jurassic–Cretaceous transition. Turiasauria distribution contributes to the understanding of European and global palaeobiogeography.

Xenoposeidon proneneukos gen. et sp. nov. is a neosauropod represented by BMNH R2095, a well-preserved partial mid-to-posterior dorsal vertebra from the Berriasian- Valanginian Hastings Beds Group of Ecclesbourne Glen, East Sussex, England. It was briefly described by Lydekker in 1893, but it has subsequently been overlooked. This speci- men's concave cotyle, large lateral pneumatic fossae, complex system of bony laminae and camerate internal structure show that it represents a neosauropod dinosaur. However, it differs from all other sauropods in the form of its neural arch, which is taller than the centrum, covers the entire dorsal sur- face of the centrum, has its posterior margin continuous with that of the cotyle, and slopes forward at 35 degrees rela- tive to the vertical. Also unique is a broad, flat area of fea- tureless bone on the lateral face of the arch; the accessory infraparapophyseal and postzygapophyseal laminae which meet in a V; and the asymmetric neural canal, small and round posteriorly but large and teardrop-shaped anteriorly, bounded by arched supporting laminae. The specimen cannot be referred to any known sauropod genus, and clearly represents a new genus and possibly a new 'family'. Other sauropod remains from the Hastings Beds Group represent basal Titanosauriformes, Titanosauria and Diplodocidae; X. proneneukos may bring to four the number of sauropod 'families' represented in this unit. Sauropods may in general have been much less morphologically conservative than is usually assumed. Since neurocentral fusion is complete in R2095, it is probably from a mature or nearly mature ani- mal. Nevertheless, size comparisons of R2095 with corre- sponding vertebrae in the Brachiosaurus brancai holotype HMN SII and Diplodocus carnegii holotype CM 84 suggest a rather small sauropod: perhaps 15 m long and 7600 kg in mass if built like a brachiosaurid, or 20 m and 2800 kg if built like a diplodocid.

A new genus and species of diplodocid sauropod (Sauropoda, Diplodocoidea), Australodocus bohetii, is described. The type material from the Upper Jurassic (Tithonian) Tendaguru Beds of Tanzania, East Africa, consists of two successive mid-cervical vertebrae. These vertebrae do not show the extreme elongation of the cervical vertebrae that is diagnostic for Tornieria, and, apart from proportional differences, exhibit four autapomorphic characters not seen in other diplodocids: (1) pleurocoel weakly developed; (2) ridge posterolateral to the anterior condyle strongly posteroventrally orientated; (3) triangular pneumatic cavity ventral to the prezygapophysis, enclosed by the lateral ramus of the centroprezygapophyseal lamina and an anteriorly extended prezygodiapophyseal lamina; and (4) prominent prezygapophyseal process pointed, laterally keeled and surpassing the prezygapophysis anteriorly. Australodocus bohetii is the second diplodocid known from Tendaguru, and thereby the second diplodocid known from Gondwana. This impedes the customary reference of isolated East African diplodocid material to Tornieria, which can now only be assigned to Diplodocidae indet. The find supports previously proposed vicariance models of diplodocid palaeobiogeography.

Vertebrae of Suuwassea demonstrate an interest- ing combination of plesiomorphies and autapomorphies among known members of the Flagellicaudata. The cranial cervical vertebrae have proportions close to Diplodocus but resemble those of Apatosaurus except by having greatly reduced cranial and caudal spinozygapophyseal laminae. As a result, they have craniocaudally compressed, caudally positioned spinous processes excavated on all sides by fos- sae. The cranial thoracic vertebrae are again similarly pro- portioned as those of Diplodocus but are morphologically similar to those of Apatosaurus. The most distinguishing feature of Suuwassea caudal vertebrae are the short, amphi- platyan, distalmost 'whiplash' caudal vertebrae. These may be either a retention of or a reversal to the plesiomorphic sauropod condition because classic flagellicaudatan, bicon- vex distalmost caudals occur in the Middle Jurassic of England.

A relatively well–preserved specimen of Cetiosaurus oxoniensis, from the Middle Jurassic (Bajocian) of Rutland, United Kingdom, is described in detail. The material includes a nearly complete cervical series, representative dorsal vertebrae, a fragment of sacrum, anterior caudals, the right femur, and numerous rib and limb fragments. Contrary to previous suggestions that this specimen possesses 14 cervical and ten dorsal vertebrae, it seems more probable that there were at most 13 cervicals and at least 12 dorsals. The vertebral column displays several autapomorphic features which supplement the generic diagnosis of Cetiosaurus, including: (1) a stout, anteriorly directed process located at the top of the neural spine of the twelfth (?) cervical vertebra; and (2) the presence of lateral pits, separated by a thin midline septum, below the transverse processes of middle dorsal vertebrae. Cladistic analysis indicates that Cetiosaurus is probably the sister–taxon to the advanced neosauropod clade. This relationship affects the distribution of particular character states that have played an important role in determining sauropod phylogeny.