Hasil untuk "Fossil man. Human paleontology"

WANG Yi-Duo, PAN Yue, ZHANG Ying-Qi

Linsangs (Prionodon Horsfield, 1822) are small, arboreal feliform carnivorans that live in the tropical and subtropical forests of Southeast Asia and southern China. Several lines of morphological evidence from the soft tissues, dentition, and basicranium support their placement in either Prionodontinae or Viverrinae of Viverridae. However, molecular evidence has not only excluded the linsangs from Viverridae but also established that they constitute a monogeneric family Prionodontidae sister to Felidae. For that reason, the examination of the skull osteology of linsangs and related taxa is necessary to better understand how morphological and molecular data - particularly morphology - have contributed to the reconstruction of the Feliformia phylogeny. During the summer field season in July of 2020, we stumbled across the carcass of a spotted linsang (P. pardicolor) in a karst cave on the outskirts of Chongzuo City. To contribute to the knowledge about the morphology of this enigmatic feliform carnivoran, we present a preliminary description of the exterior skull osteology of P. pardicolor. The craniodental morphology provides strong evidence for a closer phylogenetic relationship between P. pardicolor and Viverrinae. However, since both morphological and molecular approaches have inherent limitations, caution is urged when inferring feliform phylogeny based on either discipline alone.

David M. Alba, Souzanna Siarabi, Sara G. Arranz et al.

Abstract The distinctiveness and genus allocation of ‘Parachleuastochoerus’ valentini (Suidae: Tetraconodontinae), from the Miocene of Europe, has been controversial, being alternatively considered a junior synonym of Conohyus simorrensis. Recently described material from the Vallès-Penedès Basin (NE Iberian Peninsula) supported its distinct species status but did not discount an alternative ascription to Conohyus, largely because the lower male canine remained unknown. Here we describe all the tetraconodontine dentognathic material from the earliest Late Miocene sites of Trinxera del Ferrocarril–Sant Quirze (~11.6–11.2 Ma, MN7+8), as well as Can Feliu 2 and Poble Nou de Sant Quirze (≤11.2 Ma, MN9), comprising 134 specimens. The former locality played an important role in the resurrection of ‘Pa.’ valentini but ~70% of the available material remained unpublished. Based on metrical and qualitative comparisons with published material of this species and similarly sized tetraconodontines from Europe, we attribute the whole studied sample to ‘Pa.’ valentini. Previous reports of Parachleuastochoerus huenermanni from the site are erroneous (owing to specimen mislabeling). Our results reinforce the distinctiveness of ‘Pa.’ valentini, while its lower male canine morphology (first described herein) does not support its transfer to Conohyus. However, a cladistic analysis favors closer phylogenetic relationships with Retroporcus matritensis (a potential junior synonym of C. simorrensis) and even Versoporcus steinheimensis than with Parachleuastochoerus crusafonti (the type species of the genus). Our results thus indicate that Parachleuastochoerus, as currently conceived, is polyphyletic, although pending an in-depth revision of other European tetraconodontines we refrain from providing a new combination for ‘Pa.’ valentini.

Simon J. Linhart, Ana Zippel, Gideon T. Haug et al.

Abstract Beetle larvae are common occurrences in modern terrestrial and freshwater fauna. We can assume that this was the case in the past as well, yet fossil beetle larvae are still reported relatively rarely. Here we report fossil larval specimens of the group of click beetles, Elateridae, from Kachin amber. The specific ecological role of the larvae can be gleaned from the specimens, they are predators, most likely wood-associated. The larvae seem differentiated from other common types of predatory larvae, the most common being lacewing larvae, based on a quantitative morphological comparison of head and mandible shape. We emphasise the use of fossil beetle larvae for functional ecological comparisons, even if the exact taxonomic relationships are unclear, because they can still provide important information for palaeoecological questions.

Josefina Bodnar, Eduardo M. Morel, Eliana P. Coturel et al.

Two collections are housed in the División Paleobotánica of the Museo de La Plata, one of megafossils and the other of microscopic preparations. Both are nationally and internationally recognized. The collections began modestly with the fossil plants collected by Santiago Roth in the late 19th and early 20th centuries. From 1933, it had a great development with the donation of the personal collection of Joaquín Frenguelli. During the 1930s, 1940s, and 1950s, the materials housed in the division acquired world renown thanks to the work of Frenguelli, fundamental in the knowledge of the flora of Gondwana. However, the División Paleobotánica did not exist at that time. In the 1960s when, with Sergio Archangelsky as chief, it became independent. As the Museo de La Plata is a university museum, since the middle of the 20th century, the collections have maintained a very close relationship with the educational field, both because of the objects that are used as teaching material and because of the people who have carried out theses, internships, and scholarships in the division. The objects of the collections served for the undergraduate training of the students who later, during their postgraduate studies, incorporated many specimens into the collection. In this way, the institution’s relationship with university education functioned as a positive feedback process that made the collections grow significantly and continuously into the early 21st century.

Jinyuan Huang, Shixue Hu, Jun Li et al.

Abstract The morphology and number of elements in the Early Triassic conodont apparatus of the genus Hindeodus, particularly Hindeodus parvus (Kozur and Pjatakova, 1976), still remain controversial. In order to shed light on the apparatus composition of this iconic genus, here we report two well-preserved conodont natural assemblages of Hindeodus from the base of Member I of the Feixianguan Formation (Induan, lower Griesbachian, in age) at Shangsi section, Sichuan Province, Southwest China. These two natural assemblages preserve direct evidence of the number, morphology, and arrangement of elements in the apparatus of Hindeodus, and in particular H. parvus. The apparatus of H. parvus consists of six morphotype elements with S, M, and P positions, showing the typical ozarkodinid 15-element arrangement. The S1-S4 array comprises a set of nine ramiform elements: a crown-shaped alate element without a ‘posterior’ process situated at the S0 position, two inner pairs of digyrate elements positioned at the S1–2 positions, and two outer pairs of bipennate elements located at the S3 and S4 locations. A pair of dolabrate elements occupy the M position outside the S array. The paired P1 and P2 positions are occupied by carminiscaphate and angulate elements, respectively. The 15-element apparatus architecture for the genus, resembles the well-known template of ozarkodinid model, further indicating the conservative architecture of the apparatus in Order Ozarkodinida spanning more than 250 million years.

Hannes Löser, Andreas Wetzel, Bernhard Hostettler

Abstract Twelve solitary and platy, colonial coral taxa assigned to the families Microsolenidae, Misistellidae, Montlivaltiidae, Rayasmiliidae, and Thamnasteriidae are described and illustrated from the Callovian (Ifenthal Formation, Herznach Member) of the area of Andil near Liesberg, about 20 km WSW of the town of Basel, Switzerland. The platy growth forms and the presence of five species of the superfamily Cyclolitoidea suggests that these corals lived under low-level light conditions.

STEVEN D. SROKA, THOMAS F. HOWELLS, ANDRÉ NEL

The new “libelluloid” family Cordulibellulidae is described to accommodate a new genus and species Cordulibellula inopinata from the Eocene Green River Formation, Utah, USA. Even if its affinities remain somewhat uncertain because of the lack of information on structures others than those of the hind wing, ts putative closest relatives are known from the Late Jurassic and Early Cretaceous. Therefore, this new fossil is interpreted as a “relict” taxon surviving until the Paleogene. This new addition to the odonatan paleoentomofauna of the Green River Formation confirms the high diversity of this clade during the Paleogene and in this formation.

ARTEM KOUCHINSKY, RUARIDH ALEXANDER, STEFAN BENGTSON et al.

New assemblages of skeletal fossils chemically extracted from carbonates of the Cambrian Stage 2–Drumian Stage are reported from the lower reaches of the Lena River as well as from the Khorbusuonka, Malaya Kuonamka, and Bol’shaya Kuonamka rivers in northern part of the Siberian Platform. The fauna studied with scanning electron microscopy includes brachiopods, molluscs, hyoliths, halkieriids, chancelloriids, tommotiids, lobopodians, palaeoscolecidans, bradoriids, echinoderms, anabaritids, hyolithelminths, and sponges showing similarity to previously described fossil assemblages from Siberia, Laurentia, and Gondwana. The material includes emended descriptions of Halkieria proboscidea, Hadimopanella knappologica, Archaeopetasus typicus, and first descriptions of Hadimopanella foveata Kouchinsky sp. nov. and Archaeopetasus pachybasalis Kouchinsky sp. nov. Affinity of Archaeopetasus to chancelloriids is suggested. Finding of an in-place operculum in a planispiral shell of Michniakia minuta enables reinterpretation of this form as a hyolith, not a mollusc. The cambroclavids Cambroclavus sp. and Zhijinites clavus and the earliest echinoderms belonging to the Rhombifera and Ctenocystoidea are reported respectively from the lower Botoman stage and Botoman–Toyonian transitional beds, correlated with Cambrian Stage 4. Carbon isotopes are analysed from sections of the Chuskuna (upper Kessyusa Group), Erkeket, Kuonamka, Olenyok, Yunkyulyabit-Yuryakh, Tyuser and Sekten formations. A major part of the δ13C record is obtained from the Cambrian Stage 4–Drumian Stage strata which remain incompletely characterised by chemostratigraphy. The Lower Anomocarioides limbataeformis Carbon isotope Excursion (LACE) from the Drumian Stage of the Khorbusuonka River is introduced herein. New chemostratigraphic data are used for regional and global correlation and facilitate study of the evolutionary development of animals and faunas through the “Cambrian explosion”.

Stephen J. Godfrey, John R. Nance, Norman L. Riker

A description and analysis is given of a single physeteroid tooth, from the Neogene of the Nutrien Aurora Phosphate Mine (formerly known as the Lee Creek Mine, Aurora, North Carolina, USA), that was bitten either by the extinct megatoothed shark Otodus chubutensis or Otodus megalodon. The tooth shows three gouges, one of which also preserves raking bite traces, made as the serrations on the Otodus sp. tooth struck and cut into its surface. We do not know if these bite traces came about as a result of scavenging or active predation. However, because the bite traces occur on part of the skull, this suggests a predatory interaction. This tooth preserves the first evidence in the fossil record of a predatory/antagonistic interaction between a sperm whale and a megatoothed shark.

Lilia René Mautino, Silvina Susana Garralla

Se propone la enmienda del género Margocolporites y tres nuevas especies fósiles con sus afines actuales provenientes de la Formación Palo Pintado del Mioceno tardío, en la provincia de Salta, Argentina. Ellas son: Parihiatus aquaticus sp. nov. (Pontederia spp., Pontederiaceae), Margocolporites gleditsioides sp. nov. (Gleditsia amorphoides, Fabaceae) y Margocolporites constrictus sp. nov. (Parkinsonia aculeata, Fabaceae). A partir del análisis del registro fósil en el lapso Cretácico–Pleistoceno, se desprende que las nuevas especies constituyen para Sudamérica las primeras citas de polen afín a Pontederia, Gleditsia y Parkinsonia en el intervalo mencionado. Los antecesores de Pontederia spp., Gleditsia amorphoides y Parkinsonia aculeata ya integraban, en el Mioceno de la región, las paleocomunidades acuáticas, palustres y de bosques higrófilos y/o en galería. Se deduce también que las nuevas especies fósiles ocupaban la misma área de distribución nativa que las actuales. Este trabajo aporta consideraciones paleobiogeográficas y una actualización de la paleoflora del noroeste argentino, acrecentando el conocimiento de la historia evolutiva de las Fabaceae y Pontederiaceae.

RACHEL E. NOTTRODT, ANDREW A. FARKE

The ankle in non-avian theropod dinosaurs consists of the astragalus and calcaneum proximally and a distal series of tarsal bones capping the metatarsals. Nearly all theropods have only two distal tarsals, identified as distal tarsal 3 and distal tarsal 4. Historically, the morphology and anatomical relationships of these distal tarsals is uncertain in ornithomimosaurs due to loss and/or disarticulation; even in articulated specimens, the bones can be difficult to access. A previously undescribed ornithomimid fossil from the Kaiparowits Formation (upper Campanian) of southern Utah, USA, provides unique views of the distal tarsals in articulation with their surrounding elements, allowing the most complete assessment yet of this region in an ornithomimid from North America. Distal tarsal 3 contacts both metatarsals II and III, whereas distal tarsal 4 contacts only metatarsal IV. Distal tarsal 4 also shows a tab-like process that projects laterally. Comparison of the new fossil with other ornithomimosaurs shows that distal tarsals in Ornithomimosauria can be generalized as: (i) paired as distal tarsals 3 and 4; (ii) not fused to one another or to the proximal metatarsus; and (iii) proximo-distally compressed. The distal tarsals of ornithomimosaurs vary in the antero-posterior positioning and extent to which they cover the proximal metatarsal surface.

Nikita Zelenkov

A specialized diving lifestyle has repeatedly evolved in several lineages of modern and fossil waterfowl (Anseriformes), with the oldest previously known representative being the late Oligocene Australian oxyurine ducks Pinpanetta. However, diving specializations have never been previously documented for any of the primitive Paleogene anseriforms ( “stem-anatids”), and thus may be associated with the origin of modern anatid-like body plan. Here I describe a tarsometatarsus of a new duck-sized diving anseriform bird from the latest Eocene (late Priabonian) Kusto Svita in Eastern Kazakhstan, which predates the previously reported occurrence of diving specialization in Anseriformes by at least 6 MA. The new taxon Cousteauvia kustovia gen. et sp. nov. has an unusual and previously undocumented morphology, but partly resembles the stem-anatids Paranyrocidae and Romainvilliidae, thus representing the first known occurrence of diving adaptations in primitive non-anatid anseriforms. The evolutionary appearance of specialized waterfowl taxa in the late Eocene of Central Asia supports a view that this region might have played an important role in the evolution of morphologically derived Anseriformes. The structure of the intertarsal joint in basal and modern anseriforms is here further discussed in relation with adaptations for aquatic locomotion. The presence of elongate and evenly narrow condyles of the tibiotarsus in Anatidae and other swimming/diving birds allows a firm contact with the hyperprotracted tarsometatarsus at the initial phase of the propulsion. This morphology contrasts with the restricted condyles of Presbyornithidae, which indicate a different, strictly wading locomotory specialization. Cousteauvia obviously evolved diving specializations on the basis of a more primitive structure of the intertarsal joint.

Jerzy Dzik

A block of stromatolitic limestone found on the Angara River shore near Kodinsk, Siberia, derived from the exposed nearby Ust-kut Formation, has yielded a sample of 146 ellesmeroceratid nautiloid specimens. A minor contribution to the fossil assemblage from bellerophontid and hypseloconid molluscs suggests a restricted abnormal salinity environment. The associated shallow-water low diversity assemblage of the conodonts Laurentoscandodus triangularis and Utahconus(?) eurypterus indicates an age close to the Furongian–Tremadocian boundary. Echinoderm sclerites, trilobite carapaces, and hexactinellid sponge spicules were found in another block from the transitional strata between the Ust-kut and overlying terrigenous Iya Formation; these fossils indicate normal marine salinity. The conodont L. triangularis is there associated with Semiacontiodus iowensis and Cordylodus angulatus. This means that the stromatolitic strata with cephalopods are older than the early Tremadocian C. angulatus Zone but not older than the Furongian C. proavus Zone. The sample of nautiloid specimens extracted from the block shows an unimodal variability in respect to all recognizable aspects of their morphology. The material is probably conspecific with the poorly known Ruthenoceras elongatum from the same strata and region.

Ariana Paulina-Carabajal, Juliana Sterli, Ingmar Werneburg

Fossil turtles are one of the least studied clades in regard to endocranial anatomy. Recently, the use of non-invasive technologies, such as radiographic computed tomography (CT), increased the knowledge of the neuroanatomy of several extinct and extant taxa. Here, we provide the description of the nasal cavity, cranial endocast, and inner ear of the stem turtle Naomichelys speciosa based on digital 3D reconstructions. This terrestrial form is characterized by a nasal cavity with anteroposteriorly elongated vestibulum and a large cavum nasi proprium, traits typically related to terrestrial habits. The large olfactory region of the cavum nasi proprium suggests that olfaction was probably the most important sense for this species. Our description of N. speciosa adds novel information to the knowledge of endocranial anatomy in early turtle evolution and provides an important foundation for future analyses and comparisons.

Santiago Fernández, Juan Ochando, Manuel Munuera et al.

Resumen. Este artículo pretende una revisión crítica de los datos palinológicos del Cuaternario ibérico con particular atención al Pleistoceno Tardío y Holoceno. Se analizan aspectos relacionados con la ciclicidad climático astronómica y su influencia sobre la cubierta vegetal, los reservorios de fitodiversidad durante los estadiales, la colonización tardiglacial y holocena y el posible efecto de la acción antrópica sobre la dinámica forestal a partir del Holoceno Medio. Se comparan las zonas de influencia atlántica con las áreas de clima continental y la vertiente mediterránea. La perspectiva no es, en cualquier caso, climaticista sino histórico contingente. Palabras clave. Palinología. Paleoecología. Pleistoceno. Holoceno. España. Portugal. Quercus. Pinus. Abstract. FORESTS IN MOVEMENT. CASUÍSTICS IN THE IBERIAN PENINSULA DURING THE LATE QUATERNARY. This paper brings a critical revision of the palynological data from the Iberian Quaternary with special attention to the Late Pleistocene and Holocene. The climatic, astrononomically controlled cyclicity is analysed in the context of vegetational developments, and a discussion is provided on the phytodiversity reservoirs during glacial stadials, the Tardiglacial and Holocene forest colonisation, and the effects of anthropogenic activities on forest dynamics from Mid–Holocene onwards. Atlantic and Mediterranean regions are compared. The perspective here is not climaticist, but historical contingent. Key words. Palynology. Palaeoecology. Pleistocene. Holocene. España. Portugal. Quercus. Pinus.

Marcos G. Becerra, Ariana Paulina-Carabajal, Penélope Cruzado-Caballero et al.

The endocranial morphology of Secernosaurus koerneri (= Kritosaurus australis junior synonym), a hadrosaurid from the Upper Cretaceous of Argentina, was studied using latex and digital endocasts based on three fragmentary braincases. This new information allowed describing and comparing the neuroanatomy of this South American representative of the clade for the first time. The endocast morphology is mostly complete (except for the pituitary and the inner ear regions), and most cranial nerves and some blood vessels were reconstructed. Also, some features of the inner ear were observed in the CT scans, nonetheless its incompleteness restricts further comparisons. Secernosaurus koerneri shares its overall endocranial morphology with saurolophinid hadrosaurids, indicating a conservative brain morphology for Cretaceous hadrosaurids worldwide. The novel cranial information increases the knowledge of the neuroanatomy in hadrosaurids by adding a southern perspective, since knowledge on the endocranial anatomy of the lineage is biased by species from North America.

Pavel P. Skutschas

The early evolution of salamanders, which are one of the three living groups of lissamphibians, is not well known. Both stem- and crown-group salamanders first appeared in the Middle Jurassic (Bathonian), but subsequently had different evolutionary histories: stem salamanders were thought to have gone extinct in the Late Jurassic, while crown salamanders persist to the present day. Here, I report the discovery of an indeterminate stem salamander in the Lower Cretaceous (Aptian–Albian) Ilek Formation of Western Siberia. This is new evidence that the most basal salamanders survived beyond the Jurassic–Cretaceous boundary and co-existed with crown-group salamanders during approximately the first 40 million years of the known history of salamanders. The recognition of stem salamanders in the Early Cretaceous of Western Siberia adds to the inventory of taxa that suggest this area was a refugium for various groups of vertebrates with Jurassic affinities.

Sergio F. Vizcaíno

Cartas para Florentino desde Patagonia. Crónica de la correspondencia édita entre los hermanos Ameghino (1882-1902)

Silvia N. Césari

Paleozoico Superior de Argentina un registro fosilífero integral en el Gondwana occidental

Leandro M. Perez

Los macroinvertebrados de la Formación Paraná: historia y diversidad de la fauna bentónica del Mioceno marino de Entre Ríos, Argentina