cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.20603058
title: Unravelling the identity of the platanistoid <i>Notocetus vanbenedeni</i> Moreno, 1892 (Cetacea, Odontoceti) from the early Miocene of Patagonia (Argentina)

description: Platanistoidea remains one of the most evolutionarily intriguing lineages of toothed whales (Odontoceti). The clade comprises mostly extinct species from the late Oligocene–early Miocene onward and a single extant riverine genus (<i>Platanista</i>). There is an ongoing debate as to the membership of Platanistoidea and the causes of their near extinction. In Patagonia (Argentina), the most abundant platanistoid recorded in the lower Miocene Gaiman Formation is <i>Notocetus vanbenedeni</i>, first described by Moreno in 1892 based on two individuals. The goal of the present contribution is to conduct an updated anatomical, palaeobiological and phylogenetic analyses of <i>Notocetus vanbenedeni</i> and hence contribute to an understanding of the evolutionary history of the Platanistoidea. Our analyses, including at least 26 individuals (12 undescribed), show that <i>Notocetus vanbenedeni</i> is a valid platanistoid taxon, recovered as part of a new clade. Among its most outstanding features, this taxon has an elevated dorsal tubercular supraorbital crest formed mainly by the frontal, the precursor of the pneumatized crest of the extant <i>Platanista</i>. <i>Notocetus vanbenedeni</i> also shows initial stages of the plesiomorphic bony connection between the earbones and skull as in <i>Platanista</i>, although the functional implications for hearing remain elusive. The nasal sac system, pterygoid sinus system and morphology of the earbones suggest that this species was able to hear high-frequency sounds and echolocate underwater, similar to extant odontocetes. Thus, <i>Notocetus vanbenedeni</i> presents a mosaic of features that suggest an intermediate platanistoid morphotype. Anatomical differences and phylogenetic analyses suggest that Peruvian specimens could not be referred to this species. The feeding apparatus of <i>Notocetus vanbenedeni</i> makes it the only combination suction-feeder recorded in the early Miocene of Patagonia and among the smallest odontocetes. Finally, the abundant records of <i>Notocetus vanbenedeni</i> in an inner shelf environment with freshwater influence suggest a possible early preference for such protected habitats.
DOI: 10.6084/m9.figshare.21187762
title: The first evidence of <i>Heosminthus</i> from North America and the phylogenetics of Sminthidae (Mammalia, Rodentia, Dipodoidea): biogeographical implications

description: The Eurasian fossil record is rich with the remains of sminthid rodents, a clade today represented by a single genus, <i>Sicista.</i> In contrast, the North American record of the family is sparse and exclusively composed of species of <i>Plesiosminthus</i>, an animal bearing a grooved incisor, during the Oligocene. This fossil record is the product of dispersal events from Eurasia. We here present the first occurrence of a smooth-incisor sminthid from North America. The new species, <i>Heosminthus teredens</i> from the Arikareean-aged Cabbage Patch beds of Montana, represents a rare occurrence of cranial material showing the clear association between incisors and cheek teeth, and the first postcranial remains for fossil sminthids. Our phylogenetic analysis, expanding on prior work, shows that <i>Heosminthus teredens</i> is most closely related to <i>Heosminthus borrae</i>, from Mongolia. In combination with published radioisotopic dating, our phylogenetic framework of sminthids provides evidence for an additional dispersal of sminthid rodents from Eurasia to North America 30 million years ago via Beringia. Our morphometric analysis of the tibia and metatarsal supports a terrestrial ecology for the new species; it is possible the animal had limited scansorial and/or saltatorial abilities. The large sample size of teeth available for the new taxon enables an analysis of morphological variation and indicates a high degree of polymorphism as well as a large size variation, even when controlling for stratigraphical and geographical range. https://zoobank.org/urn:lsid:zoobank.org:pub:B7D4245C-992F-4956-96AD-10D7CFA8E5C8
DOI: 10.6084/m9.figshare.21187762.v1
title: The first evidence of <i>Heosminthus</i> from North America and the phylogenetics of Sminthidae (Mammalia, Rodentia, Dipodoidea): biogeographical implications

description: The Eurasian fossil record is rich with the remains of sminthid rodents, a clade today represented by a single genus, <i>Sicista.</i> In contrast, the North American record of the family is sparse and exclusively composed of species of <i>Plesiosminthus</i>, an animal bearing a grooved incisor, during the Oligocene. This fossil record is the product of dispersal events from Eurasia. We here present the first occurrence of a smooth-incisor sminthid from North America. The new species, <i>Heosminthus teredens</i> from the Arikareean-aged Cabbage Patch beds of Montana, represents a rare occurrence of cranial material showing the clear association between incisors and cheek teeth, and the first postcranial remains for fossil sminthids. Our phylogenetic analysis, expanding on prior work, shows that <i>Heosminthus teredens</i> is most closely related to <i>Heosminthus borrae</i>, from Mongolia. In combination with published radioisotopic dating, our phylogenetic framework of sminthids provides evidence for an additional dispersal of sminthid rodents from Eurasia to North America 30 million years ago via Beringia. Our morphometric analysis of the tibia and metatarsal supports a terrestrial ecology for the new species; it is possible the animal had limited scansorial and/or saltatorial abilities. The large sample size of teeth available for the new taxon enables an analysis of morphological variation and indicates a high degree of polymorphism as well as a large size variation, even when controlling for stratigraphical and geographical range. https://zoobank.org/urn:lsid:zoobank.org:pub:B7D4245C-992F-4956-96AD-10D7CFA8E5C8
DOI: 10.6084/m9.figshare.21751141.v1
title: Phylogeny of the Ordovician and Silurian members of the order Atrypida

description: Brachiopods belonging to order Atrypida originated in the Middle Ordovician and went extinct in the Late Devonian. Few cladistic studies have been undertaken for this group. Here we investigate their early evolution through Silurian time. We present a parsimony-based phylogenetic analysis of 41 characters and 70 genera representing all the early taxonomic groups within the order. The stratigraphical record of the fossil genera analysed strongly aligns with the phylogeny recovered from our parsimony analysis. Most currently recognized subfamilies and families may be identified within clades, except for the Atrypinae, Idiospirinae, and the Septatrypidae. This warrants subdivision of the former and redefinition of the latter two. The subfamily Atrypinae is redefined, and a new subfamily of the Atrypidae, the Protatrypinae, is split off. Tracing character evolution across the tree indicates that the calcified spiralia and a jugum or jugal processes characterize all members of the Atrypida, except the most basal clade, the Cyclospiridae, which lacks a calcified jugum. Ribs are a homoplasious character, occurring in numerous clades throughout the tree. Darriwillian through Sandbian ages represent times with rapid evolution when most new autapomorphies seen in the atrypides evolved. This interval is the first major part of the Great Ordovician Biodiversification Event (GOBE). Solid teeth, dorsal direction of spiralia, elaborate ornamentation, and frills evolved in the latest Katian into early Silurian time. Solid teeth seen in distantly related clades from latest Katian onwards may be an analogous feature. The Late Ordovician Mass Extinction (LOME) is indicated in the stratigraphical tree together with a possible event at the end of the Aeronian. The tree supports the long-held assumptions that the Plectatrypinae evolved from the Spirigerininae. It further suggests that the genus <i>Tuvaella</i> may be included with the Davidsonioidea. Likewise, the redefined Atrypinae is a sister group of the Lissatrypidae and a derived group in the phylogenetic tree.
DOI: 10.6084/m9.figshare.20368390
title: A new podocnemidid (Pleurodira: Pelomedusoides) from the Eocene of north-western Argentina, with comments on its evolutionary relationships and palaeoenvironmental settings

description: We report a new small podocnemidid, <i>Gestemys powelli</i> gen. et sp. nov., based on one nearly complete skull, lower jaw, two shells, and remains of the appendicular skeleton belonging to two specimens from the Eocene Geste Formation of the San Antonio de la Cobres Basin, Salta Province, north-western Argentina. As in other podocnemidid genera, <i>Gestemys</i> exhibits a fully developed and medially extensive cavum pterygoidei, an incisura columellae auris enclosing the stapes and Eustachian tube, and lacks an exoccipital quadrate contact. <i>Gestemys powelli</i> bears a huge foramen palatinum posterius and a short pterygoid flange that does not reach the basisphenoid suture, exposing the cavum pterygoid. Phylogenetic analyses place <i>Gestemys powelli</i> as a member of Podocnemididae more closely related to Erymnochelyinae than Podocnemidinae. In regards to the palaeoenvironmental settings of the Palaeogene formations (Maíz Gordo and Geste) of north-western Argentina, at least two features differentiate the palaeoenvironment where <i>G. powelli</i> was recovered and those of other podocnemidid turtles from the Maíz Gordo Formation: 1) <i>G. powelli</i> was found <i>in situ</i> with very little re-working; and 2) in contrast to the muddy rocks indicating the marginal lacustrine setting and humid climate of the Maíz Gordo Formation, <i>G. powelli</i> is associated with a coarse-grained floodplain setting and a dry, temperate climate. Such differences highlight the contrasting environmental dynamics in which podocnemidid turtles lived during the Palaeogene. http://zoobank.org/urn:lsid:zoobank.org:pub:0E631DA2-053F-4BD6-91BD-2401F34A5777
DOI: 10.6084/m9.figshare.20603058.v1
title: Unravelling the identity of the platanistoid <i>Notocetus vanbenedeni</i> Moreno, 1892 (Cetacea, Odontoceti) from the early Miocene of Patagonia (Argentina)

description: Platanistoidea remains one of the most evolutionarily intriguing lineages of toothed whales (Odontoceti). The clade comprises mostly extinct species from the late Oligocene–early Miocene onward and a single extant riverine genus (<i>Platanista</i>). There is an ongoing debate as to the membership of Platanistoidea and the causes of their near extinction. In Patagonia (Argentina), the most abundant platanistoid recorded in the lower Miocene Gaiman Formation is <i>Notocetus vanbenedeni</i>, first described by Moreno in 1892 based on two individuals. The goal of the present contribution is to conduct an updated anatomical, palaeobiological and phylogenetic analyses of <i>Notocetus vanbenedeni</i> and hence contribute to an understanding of the evolutionary history of the Platanistoidea. Our analyses, including at least 26 individuals (12 undescribed), show that <i>Notocetus vanbenedeni</i> is a valid platanistoid taxon, recovered as part of a new clade. Among its most outstanding features, this taxon has an elevated dorsal tubercular supraorbital crest formed mainly by the frontal, the precursor of the pneumatized crest of the extant <i>Platanista</i>. <i>Notocetus vanbenedeni</i> also shows initial stages of the plesiomorphic bony connection between the earbones and skull as in <i>Platanista</i>, although the functional implications for hearing remain elusive. The nasal sac system, pterygoid sinus system and morphology of the earbones suggest that this species was able to hear high-frequency sounds and echolocate underwater, similar to extant odontocetes. Thus, <i>Notocetus vanbenedeni</i> presents a mosaic of features that suggest an intermediate platanistoid morphotype. Anatomical differences and phylogenetic analyses suggest that Peruvian specimens could not be referred to this species. The feeding apparatus of <i>Notocetus vanbenedeni</i> makes it the only combination suction-feeder recorded in the early Miocene of Patagonia and among the smallest odontocetes. Finally, the abundant records of <i>Notocetus vanbenedeni</i> in an inner shelf environment with freshwater influence suggest a possible early preference for such protected habitats.
DOI: 10.6084/m9.figshare.21498389
title: A new proterochampsid (Archosauriformes: Proterochampsia) from the Late Triassic of southern Brazil and the emergence of archosaurian hind limb traits

description: Characterized by an elongated snout, proterochampsids are carnivorous non-archosaur archosauriforms. The clade is endemic to South America and its fossil record extends from the early Carnian to the late Carnian/early Norian. Nesting close to Archosauria, it is a key clade for understanding the origin and evolution of archosaurian traits. Unfortunately, hind limb elements are usually poorly preserved for the group. Therefore, the hind limb anatomy of proterochampsids still lacks detailed descriptions. In the present study, we partially fill this gap with the description of a new proterochampsid represented by a complete and well-preserved hind limb. <i>Stenoscelida aurantiacus</i> gen. et sp. nov. was excavated from the late Carnian/early Norian (Late Triassic) beds of southern Brazil. A phylogenetic investigation recovers the new taxon as a non-rhadinosuchine proterochampsid. The species bears an unusual set of traits for the group, which provides clues on the evolutionary origins of some muscle attachment structures. For instance, the femur of <i>Stenoscelida aurantiacus</i> gen. et sp. nov. possesses an anterior trochanter and an anterolateral scar. So far, these features have not been reported in other non-archosaurian archosauriforms. Therefore, the new specimen indicates that some typical archosaurian features evolved earlier than previously thought. The taxon also carries additional uncommon features for proterochampsids, such as an iliofibularis tubercle on the anterior margin of the fibula and a vestigial phalanx in digit V. In sum, <i>Stenoscelida aurantiacus</i> has one of the best-preserved hind limbs within Proterochampsidae and sheds light on the polarization of important traits regarding the evolutionary context of Archosauria. http://zoobank.org/urn:lsid:zoobank.org:pub:C78B7CE3-AB9B-4543-833E-B2A3FEA957D9
DOI: 10.6084/m9.figshare.21498389.v1
title: A new proterochampsid (Archosauriformes: Proterochampsia) from the Late Triassic of southern Brazil and the emergence of archosaurian hind limb traits

description: Characterized by an elongated snout, proterochampsids are carnivorous non-archosaur archosauriforms. The clade is endemic to South America and its fossil record extends from the early Carnian to the late Carnian/early Norian. Nesting close to Archosauria, it is a key clade for understanding the origin and evolution of archosaurian traits. Unfortunately, hind limb elements are usually poorly preserved for the group. Therefore, the hind limb anatomy of proterochampsids still lacks detailed descriptions. In the present study, we partially fill this gap with the description of a new proterochampsid represented by a complete and well-preserved hind limb. <i>Stenoscelida aurantiacus</i> gen. et sp. nov. was excavated from the late Carnian/early Norian (Late Triassic) beds of southern Brazil. A phylogenetic investigation recovers the new taxon as a non-rhadinosuchine proterochampsid. The species bears an unusual set of traits for the group, which provides clues on the evolutionary origins of some muscle attachment structures. For instance, the femur of <i>Stenoscelida aurantiacus</i> gen. et sp. nov. possesses an anterior trochanter and an anterolateral scar. So far, these features have not been reported in other non-archosaurian archosauriforms. Therefore, the new specimen indicates that some typical archosaurian features evolved earlier than previously thought. The taxon also carries additional uncommon features for proterochampsids, such as an iliofibularis tubercle on the anterior margin of the fibula and a vestigial phalanx in digit V. In sum, <i>Stenoscelida aurantiacus</i> has one of the best-preserved hind limbs within Proterochampsidae and sheds light on the polarization of important traits regarding the evolutionary context of Archosauria. http://zoobank.org/urn:lsid:zoobank.org:pub:C78B7CE3-AB9B-4543-833E-B2A3FEA957D9
DOI: 10.6084/m9.figshare.21276303
title: Careful amendment of morphological data sets improves phylogenetic frameworks: re-evaluating placement of the fossil <i>Amiskwia sagittiformis</i>

description: The Cambrian fossil <i>Amiskwia sagittiformis</i> has puzzled palaeontologists for more than a century, but recent re-investigation of its morphology suggested a close relationship with the bilaterian clade Gnathifera, comprising Rotifera, Gnathostomulida and Micrognathozoa. Since <i>Amiskwia</i> has already been considered closely related to Chaetognatha, this new interpretation of its morphology supports recent molecular and developmental studies finding a close phylogenetic relationship between Chaetognatha and Gnathifera. The recent re-description of the jaw apparatus of <i>Amiskwia</i> with the first phylogenetic analysis by Vinther & Parry (2019) found a rather surprising topology with <i>Amiskwia</i> and Chaetognatha being sister groups and nested inside Gnathifera. Furthermore, a subsequent paper from Caron & Cheung (2019) re-described the jaws of <i>Amiskwia</i> as very similar to the configuration found in Gnathostomulida, but did not include any phylogenetic analysis. Here we test the topology of Vinther & Parry with various parsimony and Bayesian analyses, taking into account the new description of Caron & Cheung with careful re-amendment of the matrix of Vinther & Parry. According to our results and the recent findings on the molecular phylogeny of their extant members, we suggest a new systematization of these taxa. We recovered <i>Amiskwia</i> as a stem-group chaetognath within a clade Cucullophora nov., rejecting the Caron & Cheung hypothesis of its close affinity to Gnathostomulida, and found a more consensual topology with monophyletic Gnathifera sister group to Cucullophora, all together forming the clade Chaetognathifera. Furthermore, Rotifera + Micrognathozoa form a clade named Gynognathifera nov. We discuss the characters supporting each clade and the reasons that account for the topology found by Vinther & Parry. Finally, we hope that this carefully amended matrix focused on Gnathifera, <i>Amiskwia</i> and Chaetognatha, together with a formal classification and robust phylogeny, will be of use for future studies on the palaeontology and morphology of these clades.
DOI: 10.6084/m9.figshare.21583067
title: Osteology of <i>Dashanpusaurus dongi</i> (Sauropoda: Macronaria) and new evolutionary evidence from Middle Jurassic Chinese sauropods

description: The Middle Jurassic lower Shaximiao Formation in Sichuan Province of south-western China has yielded a diverse terrestrial vertebrate fauna dominated by sauropod dinosaurs. However, many of these sauropods lack detailed descriptions or explicit phylogenetic diagnoses. Here, we present a comprehensive redescription of <i>Dashanpusaurus dongi</i>, a species of sauropod found only in the lower Shaximiao Formation. We define the revised autapomorphies of the species as follows: neural canals are sub-square in anterior dorsal vertebrae; the presence of a thin accessory lamina that contacts the prezygodiapophyseal and paradiapophyseal laminae of the middle dorsals, forming an angle of 75° to the horizontal; and four ridges on the anterodistal edge of the humerus. Often considered part of the epipophyseal-prezygapophyseal lamina, a strut invades the spinodiapophyseal fossa in the cervical and anterior dorsal vertebrae. Anatomical comparisons indicate that this feature was widespread among early-diverging Middle Jurassic eusauropod lineages. This comparative anatomical data provides an opportunity to revisit the phylogenetic position of <i>Dashanpusaurus</i> and the relationships of the neosauropod clade. Recovered as a macronarian, a better understanding of <i>Dashanpusaurus dongi</i> will allow for clarification of the origin, early evolution, and palaeogeographical distribution of neosauropods. This study also suggests that the diversity and dispersity of the neosauropod clade occurred much earlier than previously realized.
DOI: 10.6084/m9.figshare.21657643
title: A new small-bodied ankylosaurian dinosaur from the Upper Cretaceous of North Patagonia (Río Negro Province, Argentina)

description: The most representative ankylosaurian remains from Argentina have been found in sediments of the Allen Formation (Campanian–Maastrichtian) in Salitral Moreno, Río Negro Province. Several authors have discussed the identity and history of these remains. In this study, we review all published material along with some new remains in order to summarize all the knowledge about these ankylosaurs. Previously published material includes a tooth, dorsal and anterior caudal vertebrae, a femur and several osteoderms. The new remains include synsacral and caudal elements, a partial femur and osteoderms. The anatomy of the tooth, the synsacrum, the mid-caudal vertebra, the femur and the osteoderms, and the histology of the post-cervical osteoderms, support a nodosaurid identification, as proposed in previous descriptions of the Salitral Moreno material. <i>Patagopelta cristata</i> gen. et sp. nov. is a new nodosaurid ankylosaur characterized by the presence of unique cervical half-ring and femoral anatomies, including high-crested lateral osteoderms in the half rings and a strongly developed muscular crest in the anterior surface of the femur. The ∼2 m body length estimated for <i>Patagopelta</i> is very small for an ankylosaur, comparable with the dwarf nodosaurid <i>Struthiosaurus</i>. We recovered <i>Patagopelta</i> within Nodosaurinae, related to nodosaurids from the ‘mid’-Cretaceous of North America, contrasting the previous topologies that related this material with Panoplosaurini (Late Cretaceous North American nodosaurids). These results support a palaeobiogeographical context in which the nodosaurids from Salitral Moreno, Argentina, are part of the allochthonous fauna that migrated into South America during the late Campanian as part of the First American Biotic Interchange. https://zoobank.org/urn:lsid:zoobank.org:pub:FBA24443-F365-49FD-A959-10D2848C2400