BackgroundVaranidae is a clade of tiny (<20 mm pre-caudal length [PCL]) to giant (>600 mm PCL) lizards first appearing in the Cretaceous. True monitor lizards (Varanus) are known from diagnostic remains beginning in the early Miocene (Varanus rusingensis), although extremely fragmentary remains have been suggested as indicating earlier Varanus. The paleobiogeographic history of Varanus and timing for origin of its gigantism remain uncertain.Methodology/Principal FindingsA new Varanus from the Mytilini Formation (Turolian, Miocene) of Samos, Greece is described. The holotype consists of a partial skull roof, right side of a braincase, partial posterior mandible, fragment of clavicle, and parts of six vertebrae. A cladistic analysis including 83 taxa coded for 5733 molecular and 489 morphological characters (71 previously unincluded) demonstrates that the new fossil is a nested member of an otherwise exclusively East Asian Varanus clade. The new species is the earliest-known giant (>600 mm PCL) terrestrial lizard. Importantly, this species co-existed with a diverse continental mammalian fauna.Conclusions/SignificanceThe new monitor is larger (longer) than 99% of known fossil and living lizards. Varanus includes, by far, the largest limbed squamates today. The only extant non-snake squamates that approach monitors in maximum size are the glass-snake Pseudopus and the worm-lizard Amphisbaena. Mosasauroids were larger, but exclusively marine, and occurred only during the Late Cretaceous. Large, extant, non-Varanus, lizards are limbless and/or largely isolated from mammalian competitors. By contrast, our new Varanus achieved gigantism in a continental environment populated by diverse eutherian mammal competitors.

No abstract

In 1934, Barnum Brown of the American Museum of Natural History in New York (AMNH) led a large-scale dinosaur excavation in northern Wyoming, where he had found bones two years earlier. Initially, Brown expected to excavate two skeletons of sauropod dinosaurs, but soon after opening the quarry, the team realized that the site far exceeded their expectations: in the end, they unearthed approximately 3000 bones within six months and sent approximately 144 crates back to the AMNH. Due to the enormous number of bones, the site became world famous as a dinosaur graveyard, and media from all over the United States and abroad reported on the expedition. Soon after, however, the collection shifted away from a curatorial focus. What followed was a history of neglect: inappropriate storage conditions, water and fire damage, collapsing wooden boxes, and deteriorating plaster jackets.Relocation and further excavation of the quarry by the Sauriermuseum Aathal (Switzerland; SMA) from 1989 to 1991 confirmed earlier finds of skin impressions and resulted in the recognition of a novel diplodocid sauropod: Kaatedocus siberi. Given that the amount of bones found by the AMNH far exceeded those found by the SMA, a new project was started in 2017 to reassess the state and scientific value of the historic collections at AMNH. Although most of the bones are heavily fragmented, preliminary results show that overall preservation is still exceptional. Here, we reconstruct the history of the excavation, as well as past conservation and preparation procedures, and provide a report of current efforts to prepare, conserve, and catalog the material that has remained in storage since the 1930s. These current efforts show that historic collections, even after decades of neglect, can be of great and unexpected value, both for research and scientific outreach.

2017-2020, led by Emanuel Tschopp. A conservation and research program to reassess the remaining material from the Upper Jurassic dinosaur locality Howe Quarry in northern Wyoming. A detailed report of the history and the conservation program during the recent Howe Quarry Project is published in the AMNH Novitates (Tschopp et al., 2020). Keys for collection-associated data A series of information and data was collected and associated with single bone fragments, entire bones, specimens, and the collection in general during the project. This document provides keys for labelling adhered to the fragments and bones themselves, and to the various spreadsheets produced during the project. Bones. Identification of the bone either based on the quarry map, or the actual bone (if preserved). Catalog number. AMNH FARB collection number. Bones reported on the quarry map, which were articulated with cataloged specimens, but could not be identified among the material in the collections so far, are listed in brackets (e.g., "(33158)"), so that if they turn up in future among the still unprepared material, they can be identified as being part of an already cataloged specimen, and they can be incorporated in already existing catalog numbers. Some entries are followed by a question mark (e.g., "33668?"), which indicates that there is a cataloged bone of this type from this section in the collections, but there are too many of this type of bone in the section, so we are not sure which of these is the one that is still preserved. These ambiguously identified bones are also mentioned in Spreadsheet 3. Main section. Section where the bone was found, or where the largest portion of the bone was in. Corresponds often (but not always) with the jacket number. also in section. Sections, where smaller portions of the bones were located. on map? Mentions if this particular bone is drawn on the map. ambiguity on map. Specifies which bone this row is, of several bones of the same type are found in the same section(s). In Spreadsheet 3, this column indicates how many of this specific type of bone were found in the section, and provides additional information on which of those it could be. found associated with. Identifies (semi-) articulated or associated specimens based on vicinity, size, and decay pattern as recorded in the quarry map. Field notes (refer to "main section"; comments in square brackets added by E. Tschopp). Notes copied from archival documents. visible in photo (number). Catalog numbers of historic photos from the 1934 excavation now housed in the archives, on which this particular bone can be seen. Crate number. Number of the original crate, in which this bone was shipped to AMNH in 1934. Only rarely preserved. If there is more than one number, all of these numbers are equally possible. For some elements, it was possible to identify the original crate or at least exclude some options based on archival documents. found at AMNH. Lists the bones that were identified as still present in the AMNH collections so far. storage before 2...

Four neochoristoderan vertebral centra are described from the latest Cretaceous of New Jersey, USA. One specimen was recovered from the basal transgressive lag of the Navesink Formation in the area of Holmdel, New Jersey, and two others were recovered nearby and probably were derived from the same horizon. The fourth was recovered from the Marshalltown sequence in the vicinity of the Ellisdale Dinosaur Site. These vertebrae expand the geographical range of Late Cretaceous neochoristoderes in North America by over 2000 km further east, and represent the first neochoristoderan remains from the Atlantic coastal plain. To discern whether neochoristodere remains are to be expected in New Jersey, and elucidate why neochoristoderes are apparently so rare in Appalachia, we implemented ecological niche modelling to predict the range of suitable habitat for Champsosaurus, the only known genus of Late Cretaceous neochoristoderes. We found that in Appalachia, the ideal habitat of Champsosaurus probably existed slightly further north and west than the Atlantic coastal plain, and New Jersey is probably on or near the margin of this suitable habitat space. These results suggest that the occurrence of neochoristoderes in New Jersey is consistent with the habitat requirements of known Late Cretaceous neochoristoderes. These vertebrae may therefore represent the southern margin of a population of neochoristoderes that lived further inland, where latest Cretaceous sediments are not preserved. The continued recovery of material from Late Cretaceous deposits along the Atlantic coast, and review of existing collections, is encouraged to clarify the true distribution of neochoristoderes in Appalachia.

No abstract

No abstract

An unmarked crate stored for many years in the American Museum of Natural History's Division of Paleontology was opened in 2005 and found to contain large slabs of small (one- to a few-centimetre-sized) fossil tetrapod footprints that were clearly geologically very old. The lack of data on or in the crate left the contained specimens orphaned and mysterious and nothing was definitively gleaned about their age, provenance or history for over a dozen years. But when a new book on an extraordinary assemblage of Carboniferous trackways in Alabama was published in 2016, it was found to contain a few sentences that gave clues to the origin of the specimens and soon illuminated the hidden story. Not only had the tracks been amassed by George Gaylord Simpson, one of the foremost vertebrate paleontologists of the 20th Century, many are exquisitely preserved and quite important scientifically. The story of their rediscovery and ongoing interpretation is an intriguing mix of luck, revelations and probing of both the geologic and paper records.