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This paper presents new descriptions of Anacardiaceae fossil woods from the Ituzaingó Formation (late Cenozoic) at the Toma Vieja, Curtiembre, and Arroyo El Espinillo localities, Argentina. We describe eight silicified woods assigned to four different species in three genera, one of which, Parametopioxylon crystalliferum n. gen. n. sp., is new. Similarities between these three genera and the six Anacardiaceae species previously recorded from the late Cenozoic in northeastern Argentina are investigated using multivariate analysis techniques (correspondence and cluster analysis). Our study is based on 33 characters scored for 17 fossil specimens (10 AstroniumxylonBrea, Aceñolaza, and Zucol 2001; five SchinopsixylonLutz, 1979; and two Parametopioxylon n. gen.) and four extant species (Astronium balansae Engl., Astronium urundeuva Engl., Schinopsis balansae Engl., and Metopium sp.). Our main goal is to determine the wood anatomical features useful for distinguishing among these species. Results of the multivariate analyses support the previous classification where Schinopsixylon is distinguished from Astroniumxylon by having exclusively paratracheal axial parenchyma, ≥30% multiseriate rays, and multiseriate rays that are ≥5 cells wide and commonly 301–400 µm in height. Additionally, we propose that Schinopsixylon heckiiLutz, 1979 is synonymous with S. herbstiiLutz, 1979. A diagnostic key for the fossil species studied is given. Wood anatomy of Anacardiaceae fossil woods from Argentina (late Cenozoic) suggests a warm, dry to semi-humid climate for this region, supporting previous studies.
Among Permian smaller foraminifers, the genus Dagmarita is one of the most studied due to its worldwide distribution. The detailed study of the Zal (NW Iran) and Abadeh (Central Iran) stratigraphic sections led to redescription of the genus Dagmarita and its taxonomic composition. In Dagmarita, a peculiar generic morphological character, represented by a secondary valvular projection, has been detected for the first time among globivalvulinid foraminifers. The phylogeny of Dagmarita, and in particular its ancestor Sengoerina, is discussed and the new species, D. ghorbanii n. sp. and D. zalensis n. sp., are introduced. Analogies and differences among all the species belonging to Dagmarita are highlighted and morphological features of the new taxa are shown in 3D reconstructions, useful for understanding differently oriented sections of the specimens in thin section.
Fifteen species of stylasterids from the late Miocene (Messinian) are reported from the Carboneras region of southeastern Spain. Eleven of these species are described as new: Lepidopora fistulosa, Pliobothrus striatus, Pliobothrus nielseni, Distichopora patula, Stylaster (Group A) digitiformis, Stylaster multicavus, Stylaster tuberosus, Conopora forticula, Conopora alloporoides, Crypthelia zibrowii, and Crypthelia ingens. The other four have been identified as species previously described from the Recent fauna. On the basis of bathymetric ranges of similar living stylasterids and other associated fauna, the paleodepth of this fauna is estimated to be from the upper bathyal zone (200–600 m). All fossil stylasterid records, worldwide, are reviewed, resulting in four new combinations and the transfer of one species to the Bryozoa. The species reported herein increase the known number of named fossil stylasterids from 24 to 32 species.
The brachiopods collected from the Kuanyinchiao Beds (Hirnantian, uppermost Ordovician) in Meitan and Zunyi counties, northern Guizhou, include 13 species and one undetermined taxon, dominated by Hirnantia sagittifera (M'Coy, 1851) (which accounts for over one-third of the specimens), together with common Eostropheodonta hirnantensis (M'Coy, 1851). They are assigned to the Hirnantia–Eostropheodonta Community, which probably inhabited a shallow-water, nearshore Benthic Assemblage (BA) 2 to upper BA 3 environment. Population analysis shows that the community was well adapted to this environment after the first phase of the end-Ordovician mass extinction. Representative specimens of all the species are illustrated, and a new species, Minutomena missa, is described herein. The variation in Hirnantia sagittifera was noted in many of previous studies but was not statistically evidenced. Here we have measured representative specimens of that famous species from the major paleoplates and terranes in the world, along with other species assigned to the genus from South China. Having used principal component analysis (PCA), significant variations in the species are documented statistically and revised, and three nominal species, one subspecies, and two morphotypes are now reassigned to Hirnantia sagittifera sensu stricto.
Phragmolites lissoni new species is described from 11 specimens found in the Sandbian Calapuja Formation near Calapuja in Peru. The deposits are part of the Central Andean Basin. This is the hitherto only systematically described Ordovician gastropod from Peru. The species is from a brachiopod-dominated siliciclastic sequence and is associated with bryozoans. Most specimens are preserved as external molds, but latex casts yield excellent details of shell ornamentation and are used as a basis for evaluating this feature in the genus. The characteristic ornamentation of Phragmolites should be called corrugated lamellae, and the individual elements on these should be referred to as flutes. A descriptive terminology for these is suggested. The development and shape of the corrugated lamellae and flutes could be biomechanical process. A second component in lamellar formation is the alternation between regular incremental growth and formation of a lamella. Phragmolites is mainly found in shallow-water carbonate facies from tropical latitudes in the Sandbian and a mid-latitude presence in Peru is unexpected. Brachiopods from the same section in Calapuja show affinities with faunas of the Mediterranean margin of Gondwana but also weak links with Avalonia. Phragmolites is found abundantly in deeper-water facies in Laurentia, and a broad tolerance to facies and temperature and possible planktotrophy might have allowed a wide geographical dispersal of the genus. The scant record of Ordovician gastropods in the Central Andean Basin precludes comparison with the disparate record of the Ordovician gastropod taxa from the Precordillera, which do not include Phragmolites.
Computed tomographic (CT) imaging allows new accessibility to shells of gastropod fossil taxa and their extant relatives, providing new data for interpreting former systematic assignments. The highly questionable ellobiid assignment of the nonmarine gastropod genus ProtocarychiumPan, 1982 from the Lower Jurassic of Hunan, China, is reevaluated using CT imaging to assess internal aspects of the shell. By comparing these new data to those of stylommatophoran, ellobiid, and caenogastropod clades in the literature, this work reveals that Protocarychium bears no affinity to the Carychiidae, which are otherwise known only from the Cenozoic, but rather to the Paleozoic land snail family Anthracopupidae Wenz, 1938. This finding constitutes the first Asian appearance of anthracopupid snails beyond their known North American and European range. Contrary to the current opinion, we suggest the Anthracopupidae to be a basal stylommatophoran clade, which places the origin of Stylommatophora at least in the late Carboniferous.
The order Intejocerida is an enigmatic, short-lived cephalopod taxon known previously only from Early–Middle Ordovician beds of Siberia and the United States. Here we report a new genus, Cabaneroceras, and a new species, C. aznari, from Middle Ordovician strata of central Spain. This finding widens the paleogeographic range of the order toward high-paleolatitudinal areas of peri-Gondwana. A curved conch, characteristic for the new genus, was previously unknown from members of the Intejocerida.
The presence of a new taxon, Duraznovis gallegoi new genus new species is reported and described from an early Late Triassic (Carnian) deposit in Argentina. Two specimens, recovered from the Quebrada del Durazno locality, uppermost levels of the Potrerillos Formation, Cuyana Basin (Mendoza), are represented by the molds of their shield and imprints of soft parts. The identity of these specimens appears enigmatic but closely resembles in the possession of a generalized arthropod morphology and a distinctive combination of characters, to living and fossil representatives of xiphosurans (Chelicerata) and notostracans (Branchiopoda). The new fossils are associated with a rich biota comprising abundant insects, spinicaudatans, plants, and scarce fish remains living in semipermanent swamps and/or ponds within a delta plain environment with intermittent episodes of flooding, in a warm temperate and humid megamonsoonal climate during Triassic times. In this context, we analyze the taphonomic and ecological implications of their presence. Lastly, these unique specimens at the Quebrada del Durazno locality adds to the diversity of the biota, revealing the importance of this site as an exceptional paleontological Triassic deposit.
Since the end of the nineteenth century, many paleontological studies have been developed on the Middle Triassic localities of the Monte San Giorgio area (Canton Ticino, Switzerland, and Lombardy, Italy). These localities were inscribed in 2003 and 2010 in the UNESCO World Heritage List due to their paleontological relevance. New crustaceans are here described from the Kalkschieferzone member of the upper Ladinian Meride Limestone, outcropping near Besnasca-Cà del Frate (Viggiù, Italy) and Meride (Mendrisio, Switzerland). Several hundred specimens of a new genus and new species of Lophogastrida, named here Vicluvia lombardoae, improve information on Triassic mysidaceans (sensu lato), a group of shrimp-like crustaceans presently including hundreds of species worldwide distributed in marine and freshwater environments. The paper discusses the relations between Vicluvia n. gen. and the other fossil genera belonging to the same family. Vicluvia lombardoae n. gen. n. sp. exhibits two dorsally vanishing transverse grooves with their branches regularly bending toward the posterior margin of the shield and a telson with a rounded and setose apex. It was probably a euryhaline species living in a transitional environment affected by frequent and ephemeral salinity variations. Middle Triassic taphonomic windows have preserved specimens of lophogastrids in shallow basins along the Tethys, from the present Alps to China as well as in the German Basin.
An incomplete arthropod fossil, Tricarina gadvanensisFeldmann et al., 2007, from the Lower Cretaceous (Barremian–Aptian) of Iran, originally interpreted as a lobster (Malacostraca, Eucarida, Decapoda), is reinterpreted herein as a representative of a seroloid isopod crustacean (Malacostraca, Peracarida, Isopoda). The body orientation of the fossil is reversed, and the alleged cephalothoracic shield is reinterpreted as being the pleotelson. Tricarina gadvanensis, with its unique configuration of pleonite fusion (pleonites 1–4 are free, whereas pleonite 5, with still visible epimera, is fused with the pleotelson), is suggested to represent a close relative of Serolidae. The preservation of T. gadvanensis in deepwater shales speaks for conservativeness in environmental preferences of seroloid isopods for at least 125 million years.
Intermediate morphologies of a new fossil crinoid shed light on the pathway by which crinoids acquired their distinctive arms. Apomorphies originating deep in echinoderm history among early nonblastozoan pentaradiate echinoderms distinguish Tremadocian (earliest Ordovician) crinoid arms from later taxa. The brachial series is separated from the ambulacra, part of the axial skeleton, by lateral plate fields. Cover plates are arrayed in two tiers, and floor plates expressed podial basins and pores. Later during the Early Ordovician, floor plates contacted and nestled into brachials, then were unexpressed as stereom elements entirely and cover plates were reduced to a single tier. Incorporation of these events into a parsimony analysis supports crinoid origin deep in echinoderm history separate from blastozoans (eocrinoids, ‘cystoids'). Arm morphology is exceptionally well-preserved in the late Tremadocian to early Floian Athenacrinus broweri new genus new species. Character analysis supports a hypothesis that this taxon originated early within in the disparid clade. Athenacrinus n. gen. (in Athenacrinidae new family) is the earliest-known crinoid to express what is commonly referred to as ‘compound' or ‘biradial’ morphology. This terminology is misleading in that no evidence for implied fusion or fission of radials exists, rather it is suggested that this condition arose through disproportionate growth.
Upper Ordovician (Katian) strata of the Lake Simcoe region of Ontario record a spectacularly diverse and abundant echinoderm fauna known as the Brechin Lagerstätte. Despite recognition as the most taxonomically diverse Katian crinoid paleocommunity, the Brechin Lagerstätte has received relatively little taxonomic study since Frank Springer published his classic monograph on the “Kirkfield fauna” in 1911.
Using a new collection of exceptionally preserved material, we evaluate all dicyclic inadunate crinoids occurring in the Brechin Lagerstätte, which is predominantly comprised of cladids (Eucladida and Flexibilia). We document 15 species across 11 genera, including descriptions of two new genera and four new species. New taxa include Konieckicrinus brechinensis n. gen. n. sp., K. josephi n. gen. n. sp., Simcoecrinus mahalaki n. gen. n. sp., and Dendrocrinus simcoensis n. sp.
Although cladids are not commonly considered major components of the Early Paleozoic Crinoid Macroevolutionary Fauna, which is traditionally conceived as dominated by disparids and diplobathrid camerates, they are the most diverse major lineage of crinoids occurring in the Brechin Lagerstätte. This unexpected result highlights the important roles of specimen-based taxonomy and systematic revisions in the study of large-scale diversity patterns.
Falloaster anquiroisitus new genus new species (Asterozoa, Echinodermata) is described from the Floian (Early Ordovician) Garden City Formation of Idaho. The new taxon is known from a single small specimen. Because of weathering, remaining disk elements are incomplete. Dorsal surfaces of the ambulacral ossicles of two arms are available, one well preserved, whereas those of a third arm expose the ambulacrals essentially as they would appear in ventral view. Ambulacral ossicles were all but entirely lost on the remaining two arms.
Albeit asterozoan, F. anquiroisitus is not assignable at the class level. It is suggestive of the Asteroidea in presence of a domal disk, five abruptly tapering triangular, arched arms, and ambulacral ossicles vaulted to form a furrow. Ambulacral morphology, including the presence of very large podial pores, is unlike that of early asteroids. In addition, no adambulacral or other virgal-series derivatives are present; ambital framework ossicles are absent; a single series of enlarged, plate-like arm ossicles, one series on each side of the arm, come together at the arm midline; and the plate-like series were supported laterally by recurved ambulacral margins. Only remnants of the disk near the periphery survive, these of overall expression unlike any other echinoderm, including asterozoans. The mouth frame is unknown. Falloaster anquiroisitus is argued to represent an extinct lineage apart from the four recognized asterozoan classes, thereby joining a limited number of other problematic early Asterozoa.
Nanobamus macrorhinusSchoch and Milner, 2014 is a small amphibamiform temnospondyl from the early Permian Arroyo Formation of Texas. It is most readily characterized by an elongate and partially subdivided naris. This condition is superficially reminiscent of that seen in the coeval trematopids, the group to which N. macrorhinus was originally referred to under an interpretation of the holotype as a larval form. This was discounted by later workers, but the amphibamiform affinities of the specimen were not formalized until recently. The specimen has never been described in the context of its amphibamiform affinities and remains poorly characterized, never having been sampled in a phylogenetic analysis. Here we present a complete, updated osteological description of N. macrorhinus, including an improved characterization of its unique mosaic of plesiomorphic and apomorphic features and clarification of the taxon's autapomorphies. Our analysis of the taxon's phylogenetic position within Amphibamiformes shows that N. macrorhinus was recovered as diverging after basal amphibamiforms, e.g., the micropholids, and before derived amphibamiforms, e.g., the amphibamids. This is supported by the unique mixture of retained plesiomorphies, e.g., nonforeshortened postparietals and an oval choana, and apomorphies, e.g., a narrow interorbital region and slender palatal rami of the pterygoid. These results reflect the complexity of terrestrial amphibamiform diversity and provide further insight into the evolutionary history of the lissamphibian stem in terrestrial environments.
The type species Placenticeras warthiKossmat, 1895 described from the Early Cretaceous (Albian) of South India is crucial for understanding the true affinity of the genus HypengonocerasSpath, 1922. The species description was based on a holotype and was influenced by the erroneous and misleading hand sketches of the species published in the literature. We recently inspected the type specimen archived in Geological Survey of India, Kolkata, along with one additional specimen kept in Indian Museum, Kolkata, and redescribe them in the present study.