cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.13414763
title: Phylogenetic placement of <i>Adalatherium hui</i> (Mammalia, Gondwanatheria) from the Late Cretaceous of Madagascar: implications for allotherian relationships

description: The phylogenetic position of Gondwanatheria within Mammaliaformes has historically been controversial. The well-preserved skeleton of <i>Adalatherium hui</i> from the Late Cretaceous of Madagascar offers a unique opportunity to address this issue, based on morphological data from the whole skeleton. Gondwanatheria were, until recently, known only from fragmentary dental and mandibular material, as well as a single cranium. The holotype of <i>A. hui</i> provides the first postcranial skeleton for gondwanatherians and substantially increases the amount of character data available to score. We sampled 530 characters and 84 cynodonts (including 34 taxa historically affiliated with Allotheria) to test the phylogenetic relationships of Gondwanatheria and Allotheria using parsimony, undated Bayesian, and tip-dated Bayesian methods. We tested three lower dental formulae for <i>Adalatherium</i>, because its postcanines are distinctly different from those of other mammaliaforms and cannot readily be homologized with any known dental pattern. In all analyses, <i>Adalatherium</i> is recovered within Gondwanatheria, most frequently outside of Sudamericidae or Ferugliotheriidae, which is congruent with establishment of the family Adalatheriidae. The different dental coding schemes do not greatly impact the position of <i>Adalatherium</i>, although there are differences in character optimization. In all analyses, Gondwanatheria are placed within Allotheria, either as sister to Multituberculata, nested within Multituberculata, or as sister to <i>Cifelliodon</i> (and Euharamiyida), or in a polytomy with other allotherians. The composition of Allotheria varies in our analyses. The haramiyidans <i>Haramiyavia</i> and <i>Thomasia</i> are placed outside of Allotheria in the parsimony and tip-dated Bayesian analyses, but in a polytomy with other allotherians in the undated Bayesian analyses.
DOI: 10.6084/m9.figshare.13414766
title: Postcranial Morphology of <i>Adalatherium hui</i> (Mammalia, Gondwanatheria) from the Late Cretaceous of Madagascar

description: The holotype and only known specimen of <i>Adalatherium hui</i> from the Late Cretaceous of Madagascar preserves the first postcranial skeleton for the Gondwanatheria. It represents only the fourth Mesozoic mammaliaform described from articulated postcranial material from Gondwana (the others being the morganucodontans <i>Megazostrodon</i> and <i>Erythrotherium</i> and the stem therian <i>Vincelestes</i>). The postcranial skeleton of <i>Adalatherium</i> is virtually complete, and its preservation is exceptional; even costal cartilages and manual and pedal sesamoids are preserved. <i>Adalatherium</i> exhibits a variety of derived and plesiomorphic traits, probably reflective of a long evolutionary history in geographic isolation on Madagascar. Among the bizarre features are a mediolaterally compressed and anteroposteriorly bowed tibia, an unusually high number of trunk vertebrae (at least 16 thoracic and 12 lumbar vertebrae), a short tail, and a trochleated navicular facet on the astragalus. Aside from these features, <i>Adalatherium</i> displays derived and plesiomorphic characteristics in its pectoral girdle: the coracoid is well developed and contributes to half of the glenoid fossa, a separate procoracoid is absent, and the sternoclavicular joint appears to have been mobile. A ventrally facing scapular glenoid and the well-developed humeral trochlea suggest a relatively parasagittal forelimb posture. Notable features of the hind limb and pelvic girdle include a large obturator foramen similar in size to that of therians, a large parafibula, and the presence of epipubic bones. Articulation between the pelvic girdle and hind limb is in contrast to that between the pectoral girdle and the forelimb in that it is indicative of a sprawling posture.
DOI: 10.6084/m9.figshare.13414766.v1
title: Postcranial Morphology of <i>Adalatherium hui</i> (Mammalia, Gondwanatheria) from the Late Cretaceous of Madagascar

description: The holotype and only known specimen of <i>Adalatherium hui</i> from the Late Cretaceous of Madagascar preserves the first postcranial skeleton for the Gondwanatheria. It represents only the fourth Mesozoic mammaliaform described from articulated postcranial material from Gondwana (the others being the morganucodontans <i>Megazostrodon</i> and <i>Erythrotherium</i> and the stem therian <i>Vincelestes</i>). The postcranial skeleton of <i>Adalatherium</i> is virtually complete, and its preservation is exceptional; even costal cartilages and manual and pedal sesamoids are preserved. <i>Adalatherium</i> exhibits a variety of derived and plesiomorphic traits, probably reflective of a long evolutionary history in geographic isolation on Madagascar. Among the bizarre features are a mediolaterally compressed and anteroposteriorly bowed tibia, an unusually high number of trunk vertebrae (at least 16 thoracic and 12 lumbar vertebrae), a short tail, and a trochleated navicular facet on the astragalus. Aside from these features, <i>Adalatherium</i> displays derived and plesiomorphic characteristics in its pectoral girdle: the coracoid is well developed and contributes to half of the glenoid fossa, a separate procoracoid is absent, and the sternoclavicular joint appears to have been mobile. A ventrally facing scapular glenoid and the well-developed humeral trochlea suggest a relatively parasagittal forelimb posture. Notable features of the hind limb and pelvic girdle include a large obturator foramen similar in size to that of therians, a large parafibula, and the presence of epipubic bones. Articulation between the pelvic girdle and hind limb is in contrast to that between the pectoral girdle and the forelimb in that it is indicative of a sprawling posture.
DOI: 10.6084/m9.figshare.13414757
title: Dental morphology of <i>Adalatherium hui</i> (Mammalia, Gondwanatheria) from the LATE Cretaceous of Madagascar

description: The dentition in the only known specimen of <i>Adalatherium hui</i>, a gondwanatherian mammal from the Late Cretaceous of Madagascar, is markedly different from that of any previously known mammaliaform, extinct or extant. The two preserved upper incisors and single lower incisor of <i>Adalatherium</i> are each very large, open-rooted, and bear a restricted band of enamel. A shallow-rooted, rudimentary upper canine is present. The upper postcanine dentition is composed of a small, simple, two-rooted tooth mesially and four large, multiple-rooted (five roots or more) teeth distally. The latter are quadrangular in outline, each with four major cusps and three perimetric ridges bordering a central valley that opens buccally. There are four lower postcanines, also with four major cusps each. The first postcanine has two roots, but the following ones each have (or likely had) at least four. The two distal lower postcanines bear a prominent mesiobuccal basin. The cusps and other topographic features of the postcanines cannot be unambiguously homologized with those of other known mammaliaforms. Diastemata are present in the upper dentition between the incisors and canines and between the canines and postcanines, and in the lower dentition between the incisors and postcanines. <i>Adalatherium</i>, like several gondwanatherians from the Late Cretaceous and Paleogene of Argentina, retains relatively plesiomorphic, ‘normal’ radial enamel (i.e., single-layered schmelzmuster, non-decussating small prisms, interprismatic matrix anastomosing around prisms). This stands in contrast to the modified radial enamel found in other gondwanatherians from the Late Cretaceous of India and Madagascar, which exhibit prominent interrow sheets of interprismatic matrix.
DOI: 10.6084/m9.figshare.13482619.v1
title: The Late Jurassic sauropod dinosaur ‘<i>Morosaurus</i>’ <i>agilis</i> Marsh, 1889 reexamined and reinterpreted as a dicraeosaurid

description: The holotypic materials of the sauropod ‘<i>Morosaurus</i>’ <i>agilis</i>—a partial skull, proatlases, and first three cervical vertebrae—have been a taxonomic and phylogenetic mystery since their initial description by O. C. Marsh in 1889 and redescription by C. W. Gilmore in 1907. Although most species of <i>Morosaurus</i> were subsumed into <i>Camarasaurus</i> in 1919, ‘<i>M.</i>’ <i>agilis</i> was left in the defunct genus without a proper taxonomic assignment. Similarities have been noted between ‘<i>M.</i>’ <i>agilis</i> and other Morrison Formation sauropod taxa, including <i>Camarasaurus</i>, <i>Haplocanthosaurus</i>, <i>Diplodocus</i>, and Brachiosauridae, but it had yet to be included in a phylogenetic analysis. Here we present new data following additional preparation and study that suggest ‘<i>M.</i>’ <i>agilis</i> is a basally diverging member of Dicraeosauridae, along with the recently described sauropod <i>Kaatedocus</i>. Based upon its recovery as a distinct taxon, we propose that ‘<i>M.</i>’ <i>agilis</i> receive the new generic name <i>Smitanosaurus</i>, yielding the new combination <i>Smitanosaurus agilis</i>. http://zoobank.org/urn:lsid:zoobank.org:pub:6977D649-EE6B-42EE-9E1C-C043A38AC2AC
DOI: 10.6084/m9.figshare.12848670
title: The Pliocene canid <i>Cerdocyon avius</i> was not the type of fox that we thought

description: During the 1980s, a Pliocene canid from Baja California Sur, Mexico, was described as a new <i>Cerdocyon</i> species, <i>C. avius</i>. Whereas some investigators believe that <i>C. avius</i> was related to the origin of South American foxes of the tribe Cerdocyonina, others suggested that it is related to members of the tribe Vulpini. Our observations and analyses confirm that it is a vulpine with a morphological combination of features that has not been described previously: marked subangular lobe in the hemimandible, m1 hypoconulid is practically absent, and the m3 is single-cusped. We propose <i>Ferrucyon</i>, gen. nov., as a genus including at present one species, <i>F. avius</i>. In the phylogenetic analysis, this species is related to North American <i>Metalopex macconnelli</i>, and to the Eurasian <i>Nyctereutes</i> spp., which creates a relationship between the foxes of the Old and New World.
DOI: 10.6084/m9.figshare.12848670.v1
title: The Pliocene canid <i>Cerdocyon avius</i> was not the type of fox that we thought

description: During the 1980s, a Pliocene canid from Baja California Sur, Mexico, was described as a new <i>Cerdocyon</i> species, <i>C. avius</i>. Whereas some investigators believe that <i>C. avius</i> was related to the origin of South American foxes of the tribe Cerdocyonina, others suggested that it is related to members of the tribe Vulpini. Our observations and analyses confirm that it is a vulpine with a morphological combination of features that has not been described previously: marked subangular lobe in the hemimandible, m1 hypoconulid is practically absent, and the m3 is single-cusped. We propose <i>Ferrucyon</i>, gen. nov., as a genus including at present one species, <i>F. avius</i>. In the phylogenetic analysis, this species is related to North American <i>Metalopex macconnelli</i>, and to the Eurasian <i>Nyctereutes</i> spp., which creates a relationship between the foxes of the Old and New World.
DOI: 10.6084/m9.figshare.12848676
title: Paddlefish and sturgeon (Chondrostei: Acipenseriformes: Polyodontidae and Acipenseridae) from lower Paleocene deposits of Montana, U.S.A.

description: Paleocene deposits of the Tullock Member of the Fort Union Formation, Montana, U.S.A., have yielded several new specimens of †<i>Polyodon tuberculata</i>, a taxon previously described from the formation, as well as a new genus and species of sturgeon (Acipenseridae). The three new specimens of †<i>P. tuberculata</i> allow us to revise and to confirm previously reported features of the holotype, as well as to describe other features that were not preserved in the single specimen previously known. For example, we observe that (1) the left and right posttemporals overlie the left and right parietals to meet in the midline, (2) the posttemporal has a deep ventral flange, and (3) the parasphenoid extends farther posteriorly than the parietals. The new sturgeon is fairly small, and not well preserved. It can be distinguished from all other acipenserids by a combination of features, including kite-shaped dorsal scutes bearing a strong median ridge, lateral scutes that vary in shape from rhomboid to irregularly shaped elements, a large triangular scute behind the anal fin, and numerous small rhomboid scales covering the caudal skeleton. It cannot be included in any currently known genus and is here named †<i>Engdahlichthys milviaegis</i>, gen. et sp. nov.
DOI: 10.6084/m9.figshare.12848676.v1
title: Paddlefish and sturgeon (Chondrostei: Acipenseriformes: Polyodontidae and Acipenseridae) from lower Paleocene deposits of Montana, U.S.A.

description: Paleocene deposits of the Tullock Member of the Fort Union Formation, Montana, U.S.A., have yielded several new specimens of †<i>Polyodon tuberculata</i>, a taxon previously described from the formation, as well as a new genus and species of sturgeon (Acipenseridae). The three new specimens of †<i>P. tuberculata</i> allow us to revise and to confirm previously reported features of the holotype, as well as to describe other features that were not preserved in the single specimen previously known. For example, we observe that (1) the left and right posttemporals overlie the left and right parietals to meet in the midline, (2) the posttemporal has a deep ventral flange, and (3) the parasphenoid extends farther posteriorly than the parietals. The new sturgeon is fairly small, and not well preserved. It can be distinguished from all other acipenserids by a combination of features, including kite-shaped dorsal scutes bearing a strong median ridge, lateral scutes that vary in shape from rhomboid to irregularly shaped elements, a large triangular scute behind the anal fin, and numerous small rhomboid scales covering the caudal skeleton. It cannot be included in any currently known genus and is here named †<i>Engdahlichthys milviaegis</i>, gen. et sp. nov.
DOI: 10.6084/m9.figshare.13240918
title: Insights on the Dental Evolution of Walruses Based on New Fossil Specimens from California

description: Twelve new specimens of fossil walruses are described from four Miocene units in California. The new material represents five taxa: (1) a specimen from the Santa Margarita Formation referred to <i>Imagotaria downsi</i>; (2) a specimen from the Valmonte Diatomite Member of the Monterey Formation referred to cf. <i>Pontolis magnus</i>; (3) six specimens from the Monterey Formation referred to a new species of <i>Pontolis</i> (<i>Pontolis barroni</i>, sp. nov.); (4) one specimen from the Oso Member of the Capistrano Formation referred to a new species of <i>Pontolis</i> (<i>Pontolis kohnoi</i>, sp. nov.); (5) three specimens from the Oso Member referred to a new genus and species (<i>Osodobenus eodon</i>, gen. et sp. nov.). A phylogenetic analysis suggests that both the Dusignathinae and an expanded concept of the genus <i>Pontolis</i> represent monophyletic groups. We provide phylogenetic definitions for clade names of odobenids. Two of the new species are represented by specimens of males, females, and juveniles. Analysis of these specimens shows that the dental anatomy of later diverging basal odobenids is more variable than previously considered. The specific pattern of variation is lineage specific and likely corresponds to the intermediate dental morphology of late Miocene odobenids. <i>Osodobenus eodon</i>, gen. et sp. nov., is the first basal odobenid with tusk-like canines, a longitudinally arched palate, and an enlarged infraorbital foramen. These features are plausibly correlated with benthic suction feeding in the odobenins (Pliocene to Recent) and so <i>Os. eodon</i> may represent a case of convergent evolution of benthic feeding in the late Miocene. http://zoobank.org/urn:lsid:zoobank.org:pub:530A114B-46E9-4E6F-A847-8B17FAFD4327
DOI: 10.6084/m9.figshare.13240918.v2
title: Insights on the Dental Evolution of Walruses Based on New Fossil Specimens from California

description: Twelve new specimens of fossil walruses are described from four Miocene units in California. The new material represents five taxa: (1) a specimen from the Santa Margarita Formation referred to <i>Imagotaria downsi</i>; (2) a specimen from the Valmonte Diatomite Member of the Monterey Formation referred to cf. <i>Pontolis magnus</i>; (3) six specimens from the Monterey Formation referred to a new species of <i>Pontolis</i> (<i>Pontolis barroni</i>, sp. nov.); (4) one specimen from the Oso Member of the Capistrano Formation referred to a new species of <i>Pontolis</i> (<i>Pontolis kohnoi</i>, sp. nov.); (5) three specimens from the Oso Member referred to a new genus and species (<i>Osodobenus eodon</i>, gen. et sp. nov.). A phylogenetic analysis suggests that both the Dusignathinae and an expanded concept of the genus <i>Pontolis</i> represent monophyletic groups. We provide phylogenetic definitions for clade names of odobenids. Two of the new species are represented by specimens of males, females, and juveniles. Analysis of these specimens shows that the dental anatomy of later diverging basal odobenids is more variable than previously considered. The specific pattern of variation is lineage specific and likely corresponds to the intermediate dental morphology of late Miocene odobenids. <i>Osodobenus eodon</i>, gen. et sp. nov., is the first basal odobenid with tusk-like canines, a longitudinally arched palate, and an enlarged infraorbital foramen. These features are plausibly correlated with benthic suction feeding in the odobenins (Pliocene to Recent) and so <i>Os. eodon</i> may represent a case of convergent evolution of benthic feeding in the late Miocene. http://zoobank.org/urn:lsid:zoobank.org:pub:530A114B-46E9-4E6F-A847-8B17FAFD4327
DOI: 10.6084/m9.figshare.13341509
title: Late Pleistocene Mammals from Kibogo, Kenya: Systematic Paleontology, Paleoenvironments, and Non-Analog Associations

description: We report on the Late Pleistocene (36–12 ka) mammals from Kibogo in the Nyanza Rift of western Kenya, providing (1) a systematic description of the mammal remains, (2) an assessment of their paleoenvironmental implications, and (3) an analysis of the biogeographic implications of non-analog species associations. Kibogo has yielded one of the largest paleontological assemblages from the Late Pleistocene of eastern Africa, and it is dominated by grassland ungulates (e.g., equids and alcelaphin antelopes), including an assortment of extralimital (e.g., <i>Equus grevyi</i>, <i>Ceratotherium simum</i>, <i>Redunca arundinum</i>) and extinct species (<i>Syncerus antiquus</i>, <i>Damaliscus hypsodon</i>, <i>Megalotragus</i> sp.). The composition of the fauna, in conjunction with the soils and topography of the region, indicate the local presence of edaphic grassland situated within a broader environment that was substantially grassier and likely drier than at present. In contrast to non-analog faunas from higher latitudes (e.g., North America and western Eurasia), the climatic niches of non-analog species associations strongly overlap, indicating that non-analog climate regimes during the Late Pleistocene of eastern Africa are not necessary to account for the former association of presently allopatric species. The Kibogo faunas add to a growing body of evidence implying that the composition of present-day African herbivore communities is distinct from those of the geologically recent past.
DOI: 10.6084/m9.figshare.13341509.v2
title: Late Pleistocene Mammals from Kibogo, Kenya: Systematic Paleontology, Paleoenvironments, and Non-Analog Associations

description: We report on the Late Pleistocene (36–12 ka) mammals from Kibogo in the Nyanza Rift of western Kenya, providing (1) a systematic description of the mammal remains, (2) an assessment of their paleoenvironmental implications, and (3) an analysis of the biogeographic implications of non-analog species associations. Kibogo has yielded one of the largest paleontological assemblages from the Late Pleistocene of eastern Africa, and it is dominated by grassland ungulates (e.g., equids and alcelaphin antelopes), including an assortment of extralimital (e.g., <i>Equus grevyi</i>, <i>Ceratotherium simum</i>, <i>Redunca arundinum</i>) and extinct species (<i>Syncerus antiquus</i>, <i>Damaliscus hypsodon</i>, <i>Megalotragus</i> sp.). The composition of the fauna, in conjunction with the soils and topography of the region, indicate the local presence of edaphic grassland situated within a broader environment that was substantially grassier and likely drier than at present. In contrast to non-analog faunas from higher latitudes (e.g., North America and western Eurasia), the climatic niches of non-analog species associations strongly overlap, indicating that non-analog climate regimes during the Late Pleistocene of eastern Africa are not necessary to account for the former association of presently allopatric species. The Kibogo faunas add to a growing body of evidence implying that the composition of present-day African herbivore communities is distinct from those of the geologically recent past.
DOI: 10.6084/m9.figshare.13200000
title: A Basal Nonmammaliaform Cynodont from the Permian of Zambia and the Origins of Mammalian Endocranial and Postcranial Anatomy

description: Nonmammaliaform cynodonts were a diverse group of Permo-Triassic synapsids whose morphological evolution documented the beginning of many classic mammalian traits. Here, we describe a new basal cynodont from the upper Permian Madumabisa Mudstone Formation of Zambia’s Luangwa Basin as <i>Nshimbodon muchingaensis</i> gen. et sp. nov. The holotype, a relatively complete and undistorted cranium and articulated mandible with associated postcranial elements, is interpreted as the most complete and well-preserved example of a charassognathid cynodont, and preserves hitherto unknown details of charassognathid endocranial and postcranial anatomy. A phylogenetic analysis of 111 morphological characters from 25 therapsid taxa (including 15 Permo-Triassic cynodonts) supports a sister-taxon relationship between <i>Nshimbodon</i> and <i>Abdalodon</i>, including them with <i>Charassognathus</i> in a monophyletic Charassognathidae, and placing the family near the base of Cynodontia. In addition to its phylogenetic importance, <i>Nshimbodon</i> provides evidence of correlated transformations in the feeding system, neck, and shoulder, which are consistent with novel mammal-like locomotor and feeding mechanics in the earliest cynodonts. Lastly, given previous reports of charassognathids in the Karoo Basin of South Africa, the occurrence of <i>Nshimbodon</i> indicates that charassognathids, like the basal cynodont <i>Procynosuchus</i>, were geographically widespread in southern Pangea by Lopingian times. Continued collecting in the Madumabisa Mudstone Formation will lead to a better understanding of the formation’s Permian cynodont diversity and biostratigraphy, as well as the biogeographic structure of southern Pangean vertebrate assemblages prior to the Permo-Triassic mass extinction. http://zoobank.org/urn:lsid:zoobank.org:pub:143CE9D3-5742-4E92-B48F-164685F0907C