Tom T.P. Van Der Linden, Jonathan J.W. Wallaard, Maarten De Rijke
et al.
Although numerous fossils have been excavated and described from the Upper Cretaceous (Maastrichtian) Lance Formation, eggs and eggshell remains are rare and have yet to be described in detail. Here, we provide the first description of an eggshell found in the Lance Formation in eastern Wyoming. The eggshell can be attributed to the oofamily Ovaloolithidae, and is most comparable to the oogenus Ovaloolithus based on the smooth outer surface, the eggshell thickness, the closely packed shell units, and the presence of two layers. The eggshell can tentatively be ascribed to either ornithopod or non-avian theropod dinosaurs. This new eggshell expands our understanding of the geographical distribution of ovaloolithid ootaxa throughout the uppermost Cretaceous of North America, having been previously described from the Maastrichtian North Horn Formation of Utah.
Abstract. Lake Victoria, which is bordered by Uganda, Tanzania, Kenya, and has a catchment that extends to Rwanda and Burundi, is home to the largest human population surrounding any lake in the world and provides critical resources across eastern Africa. Lake Victoria is also the world's largest tropical lake by surface area, but it is relatively shallow and without a major inlet, making it very sensitive to changes in climate, and especially hydroclimate. Furthermore, its size creates abundant habitats for aquatic fauna, including the iconic hyper-diverse cichlids, and serves as a major geographic barrier to terrestrial fauna across equatorial Africa. Given Lake Victoria's importance to the eastern African region, its sensitivity to climate, and its influences on terrestrial and aquatic faunal evolution and dispersal, it is vital to understand the connection between the lake and regional climate and how the lake size, shape, and depth have changed through its depositional history. This information can only be ascertained by collecting a complete archive of Lake Victoria's sedimentary record. To evaluate the Lake Victoria basin as a potential drilling target, ∼ 50 scientists from 10 countries met in Dar es Salaam, Tanzania, in July 2022 for the International Continental Scientific Drilling Program (ICDP)-sponsored Lake Victoria Drilling Project (LVDP) workshop. Discussions of the main scientific objectives for a future drilling project included (1) recovering the Pleistocene and Holocene sedimentary records of Lake Victoria that document the dynamic nature of the lake, including multiple lacustrine and paleosol sequences; (2) establishing the chronology of recovered sediments, including using extensive tephra fingerprinting and other techniques from deposits in the region; (3) reconstructing past climate, environment, lacustrine conditions, and aquatic fauna, using an integrated multi-proxy approach, combined with climate and hydrologic modeling; and (4) connecting new records with existing sedimentary snapshots and fossils exposed in deposits around the lake, tying archaeological, paleontological, sedimentological, tectonic, and volcanic findings to new drilling results. The LVDP provides an innovative way to address critical geological, paleontological, climatological, and evolutionary biological questions about Quaternary to modern landscapes and ecosystems in eastern Africa. Importantly, this project affords an excellent opportunity to help develop conservation and management strategies for regional responses to current and future changes in climate, land use, fisheries, and resiliency of at-risk communities in equatorial Africa.
María Victoria Paredes-Aliaga, Héctor Botella, Alejandro Romero
Abstract Dental microwear analysis is a well-established technique that provides valuable information about the diets of extant and extinct taxa. It has been used effectively in most major groups of vertebrates. However, in chondrichthyans, these methods have been implemented only recently in the form of dental microwear texture analysis, with conflicting results. Causes intrinsic to chondrichthyan biology, such as limited food-to-tooth contact, low diversity in terms of trophic categories or fast tooth replacement, have been suggested to reduce diet-related wear on individual teeth, hindering the use of this approach for reliable dietary reconstruction. Here, we explored the relationship between diet and dental microwear in chondrichthyans by using 2D analysis, which can provide finer-scale identification and accurate definition of scratch morphology from tooth surfaces a priori. Scratches were counted and measured on the teeth of 34 extant elasmobranchs grouped into three categories (piscivorous, durophagous and generalist) according to dietary preferences. Our results revealed specific patterns of tooth microwear as a function of dietary abrasiveness, enabling the discrimination of trophic groups and thus establishing a useful comparative framework for inferring aspects of trophic ecology in fossils. We then used this information to study dental microwear in six fossil species from the same locality and stratigraphic levels. First, analyses of the enameloid surfaces of the fossil show that post-mortem alterations are distinguishable, allowing reliable quantification of diet-related ante-mortem microwear signatures. Discriminant analysis allowed the recognition of microwear patterns comparable to those of living sharks and linked them to specific trophic groups with high probability levels (> 90%). Thus, microwear features developing on chondrichthyan teeth during feeding are intense enough to retain information regarding diet preferences. 2D microwear analysis can track this information, proving to be a useful tool for providing significant information not only about diet but also about oral processing mechanisms in extinct chondrichthyans.
Giovanni Bianucci, Walter Sielfeld, Nicole A. Olguin
et al.
The evolutionary history of the beaked whales (Ziphiidae), odontocetes nowadays adapted to deep diving, is well known thanks to a significant fossil record mainly from the deep ocean floors. A partial cranium of a ziphiid recovered from Plio-Pleistocene deep sea deposits (about 1000 m) off the port of Pisagua, northern Chile, during fishing activity is here described and referred to the new species Ihlengesi changoensis. Ihlengesi changoensis differs from the type species Ihlengesi saldanhae, from the sea floor off South Africa, by having a more elongated premaxillary sac fossa and consequently a more anteriorly located premaxillary foramen; dorsal margin of each premaxillary crest sloping markedly ventrolaterally and generating an acute dorsal profile of the vertex in anterior view; less anterolateral extension of the right nasal forming part of the premaxillary crest; lateral margins of the nasals not anteriorly diverging but weakly convex; nasofrontal suture anteriorly pointed. The phylogeny supports a sister-taxon relationship between I. changoensis and I. saldanhae, both members of the crown ziphiids Hyperoodontinae. Ihlengesi changoensis shares with I. saldanhae and other fossil ziphiids a small body size (estimated length 3.5 m) supporting the hypothesis that in the past small beaked whales (<4 m) were more common than today. Such recent shift of the ziphiids towards a larger size could be the result of a progressive change of diet from fish to cephalopods, to the competition with the delphinids, and the predatory impact of the white shark Carcharodon carcharias and/or of the killer whale Orcinus orca. This new Chilean ziphiid further supports the hypothesis that crown beaked whales originated and firstly dispersed in the oceanic waters of the Southern Hemisphere. Their radiation and geographical distribution could have been driven by the southern oceanic circulation and related localized concentration of trophic resources in high productivity upwelling areas.
Durante el Pleistoceno, América del Sur tenía varios géneros y especies de grandes cánidos hipercarnívoros, los cuales se extinguieron completamente al final de esta época. En este trabajo se presenta una revisión sistemática exhaustiva del grupo (cuatro géneros y siete especies), sobre la base de nuevos análisis cladísticos que también contemplan información genómica y un estudio de la variación intraespecífica en cánidos. Se discuten los resultados generados sobre la filogenia, sistemática, bioestratigrafía y biogeografía de los cánidos sudamericanos. Se sinonimizó Protocyon orcesi con Protocyon troglodytes y Canis nehringi con Aenocyon dirus. El género Theriodictis sería parafilético por lo que Theriodictis tarijensis fue transferido a Protocyon. “Canis” gezi claramente no pertenece al género Canis. Las distribuciones de A. dirus y P. troglodytes llegarían hasta la región pampeana y México, respectivamente. Por otro lado, se restringió a la región pampeana la distribución de Theriodictis. El carácter fragmentario de varios taxones de América del Norte y del Sur complican su ubicación filogenética y las interpretaciones biogeográficas y evolutivas, pero se pueden inferir varios eventos inmigratorios desde América del Norte y Central y algunos posteriores en sentido contrario, así como también una diversificación importante dentro de América del Sur. Nuevos ejemplares bien preservados son necesarios para evaluar la presencia de Chrysocyon y Theriodictis fuera de América del Sur y la asignación sistemática de los restos de cánidos de los sitios de Orocual (Venezuela). La evidencia disponible no permite corroborar la presencia de grandes cánidos con anterioridad al Ensenadense (>1,8 Ma).
ANDRZEJ PISERA, MARIA ALEKSANDRA BITNER, JANE FROMONT
We describe two new genera of phymaraphiniid lithistid sponges Twertupia gen. nov. and Pickettispongia gen. nov.
from the upper Eocene Pallinup Formation of South Western (SW) Australia based on new, rich and very well preserved
material. Type material of these two genera, earlier described from poorly preserved material, were originally attributed
to Thamnospongia subglabra and Stachyspongia neoclavatela (in case of species of Twertupia), and to Discoderma tabelliformis
(case of species of Pickettispongia). This is the first record of bodily preserved phymaraphiniid sponges from
Eocene rocks, as well as from the southern hemisphere. We discuss extant and fossil representatives of Phymaraphiniidae
and their geographical distribution, concluding that the present day occurrences of these sponges are the result of a much
larger Mesozoic Tethyan distribution.
Rosemarie Christine Baron-Szabo, Karl Tschanz, Peter Kürsteiner
Abstract From the Vitznau Marl (lower Valanginian) at the locality Wart in northeastern Switzerland (Alpstein area), 18 species from 17 genera and 13 families are described, including the genera Actinaraea, Actinastrea, Adelocoenia, Aplosmilia, Axosmilia, Complexastrea, Cyathophora, Dermosmilia, Fungiastraea, Heterocoenia, Latiastrea, Montlivaltia, Placophyllia, Pleurophyllia, Stylophyllopsis, Thamnoseris, and specimens showing affinities to solitary stylophyllids. The corals from the Vitznau Marl were derived from a limestone–marl alternation that is fossiliferous and clay-rich at the base (Vitznau Marl), containing crinoids, bryozoans, and sparse reworked corals and sponges. The coral fauna is distinctly dominated by forms belonging to the category of lowest to no polyp integration (50%), followed by species of the cerioid-plocoid group (33%) and forms having the highest polyp integration (thamnasterioid; 17%). With regard to polypar size, the Wart fauna is dominated by corals having large-size (> 9 mm) polyps (= 39%), followed by corals having medium- (> 2.5‒9 mm; 33%) and small-size polyps (up to 2.5 mm; 28%). Based on morphological features, the fauna from the Vitznau Marl closely corresponds to coral assemblages that are subjected to near-chronic, moderate sediment-turbidity stress that is punctuated by high-stress events, and that are largely or entirely heterotrophic. No coral fabric was observed that would suggest a biohermal development. But in a very small number of places, structures are present which might be fragments of crusts of microbialites, pointing to the hypothesis that at least a few of the corals might have been a part of some kind of bioconstruction. At the species-level, the fauna of the Vitznau Marl shows either no or very little affinities to other Valanginian assemblages such as to the fauna of Hungary (4.3%), followed by the associations of Ukraine, Switzerland (non-Vitznau), Spain (SpII), and Bulgaria. At the genus-level, the Wart fauna shows low correspondence to the fauna of Spain (SpII) (14.5%), followed by the assemblages of Hungary, Bulgaria, and Ukraine. In addition to the Vitznau Marl corals, an account of all Valanginian coral faunas published before early 2021 is given, including their paleogeographic distribution, as well as their taxonomic and morphological characterization. For this preliminary study, a total of 206 coral species belonging to 97 genera found in the coral assemblages of the Valanginian were included. At both the genus- and the species-levels, colonial taxa are most abundant (colonial genera: 89%; colonial species 90%). The vast majority of the Valanginian genera already occurred in older strata. Only 11 genera (out of 97 = 11%) are newly recorded. The Valanginian faunas having the largest number of solitary taxa lived in both (sub-) paratropical to warm-temperate areas, and in arid regions. The coral faunas of the Valanginian are distinctly dominated by corals of well-established microstructural groups. Only 13% of the species from 24% of the genera belong to “modern” groups. Compared to the situation in the Berriasian which showed that 9% of the species and 17% of the genera belonged to modern microstructural groups, the occurrence of “modern” groups significantly increased during the Valanginian.
The Lujiatun Unit of the Yixian Formation yields the
only three-dimensionally preserved fossils from the Early
Cretaceous Jehol Biota and crops out only in western Liaoning.
Here, we report a new fossil site for the Jehol Biota
with three-dimensionally preserved fossils from Ningcheng,
Inner Mongolia. The fossils that have been discovered at
this new site are predominantly dinosaurs and include a
Sinovenator-like troodontid skeleton, three isolated sauropod
teeth, some disarticulated skeletons of neornithischians
and ceratopsians, and fragmentary lower jaws from a
lizard and a mammal. The faunal composition, as well as
the lithological features of the fossil beds, are comparable
with those of the Lujiatun Unit of the Yixian Formation at
Beipiao, western Liaoning, China. This discovery expands
the geographical range of the Lujiatun-like dinosaurian assemblage
of the Jehol Biota, and increases the biodiversity
of the Jehol Biota in the Ningcheng Basin, China.
Esta contribución tiene el propósito de dar a conocer la presencia de las subespecies de Saetograptus argentinus para el Silúrico de la Precordillera Central de San Juan, Argentina. Las muestras de roca fueron obtenidas en el tramo medio–superior de la Formación Los Espejos, aflorante en la quebrada Ancha, área de Talacasto, y se describen como coquinas de cemento pelítico-carbonático a calcarenitas. Desde el punto de vista paleontológico, contienen una asociación de graptolitos, entre los que se identifican las subespecies Saetograptus argentinus argentinus y S. a. robustus, acompañados por braquiópodos, bivalvos, trilobites, tentaculitoideos y ostrácodos. La presencia de dicha graptofauna, asociada a registros bioestratigráficos previos de conodontes y braquiópodos, permite asignar una edad ludloviana a las rocas portadoras. El presente trabajo significa la primera descripción de ambas subespecies para Precordillera y permite correlacionar la sección de quebrada Ancha con otras localidades fosilíferas de la Precordillera argentina como cerro del Fuerte, cerro La Chilca y Loma de Los Piojos, así como con afloramientos de la Formación Kirusillas en Bolivia.
Christian Klug, Günter Schweigert, René Hoffmann
et al.
Abstract Especially in Lagerstätten with exceptionally preserved fossils, we can sometimes recognize fossilized remains of meals of animals. We suggest the term leftover fall for the event and the term pabulite for the fossilized meal when it never entered the digestive tract (difference to regurgitalites). Usually, pabulites are incomplete organismal remains and show traces of the predation. Pabulites have a great potential to inform about predation as well as anatomical detail, which is invisible otherwise. Here, we document a pabulite comprising the belemnite Passaloteuthis laevigata from the Toarcian of the Holzmaden region. Most of its soft parts are missing while the arm crown is one of the best preserved that is known. Its arms embrace an exuvia of a crustacean. We suggest that the belemnite represents the remnant of the food of a predatory fish such as the shark Hybodus.
Zdeněk Vašíček, Błażej Błażejowski, Andrzej Gaździcki
et al.
The first Early Cretaceous (Valanginian–Hauterivian) ammonite fauna from the lower part of the Kościeliska Marl Formation (Wściekły Żleb Member) of the Lower Sub-Tatric (Krížna) Nappe, in the Lejowa Valley of the Tatra Mountains are described. The fauna is precisely placed in the succession and consists of five species: Olcostephanus densicostatus, Spitidiscus cf. cankovi, Criosarasinella cf. subheterocostata, Crioceratites primitivus, and Crioceratites coniferus and additionally an aptychus Didayilamellaptychus seranonis. Remarkable are the valves of anomiid bivalves attached to body chamber of large size heteromorph ammonite C. primitivus. Moreover, a variety of stratigraphically important organic-walled dinoflagellate cysts are recovered from this locality. Dinoflagellates: Cymososphaeridium validum, Circulodinium vermiculatum, and representatives of Bourkidinium define the Upper Valanginian–Lower Hauterivian Sentusidinium sp. A Dinocyst Subzone of the Cymososphaeridium validum Zone. The character of deposits, the palynofacies, and associations of dinoflagellate cysts indicate a calm marine outer neritic environment.
Magdalena Łukowiak, Andrzej Pisera, Tetiana Stefanska
Despite being reported from various localities and stratigraphic intervals, knowledge of the siliceous sponges from the Cenozoic of Eastern Europe remains surprisingly limited. Studies assessing their diversity are almost exclusively in Russian and rather hard to obtain. The most comprehensive elaboration of the sponge spicules from the Paleogene of the East European Platform was published in 2003 and deals with material from Ukraine, Russia, Belarus, and Lithuania. However, the classification in that paper is purely artificial and extremely difficult to interpret according to modern biological criteria. A reassessment of this material is carried out, with the aim of revising all morphotypes of spicules, and identifying them to the lowest possible taxonomic level. Results suggest that the assemblage is much more diverse than previously thought, including members of 24 demosponge families (class Demospongiae), one homoscleromorph (class Homoscleromorpha), and at least one hexactinellid (class Hexactinellida). Our improved understanding of the diversity of Paleogene sponge fauna of the East European Platform will have implications for the interpretation of the past and future ecological and paleobiogeographic studies.
In this contribution, the first anuran fossils from classical Santacrucian localities of the Río Santa Cruz are described. According to proportions and features recognized in the few skull elements recorded, the remains are assigned to the southern gondwanan Calyptocephalella cf. canqueli. This identification extends geographically the distribution of the fossil taxon, defining this species to be a conspicuous component of the aquatic environments of the warm temperate climatic biotas during the late Oligocene – early Miocene times of Patagonia.
Pyramidalia is a brachiopod genus with Spirifera simplex as the type species. Imprecise diagnosis and misidentification of the material studied in the original description resulted in a plethora of interpretations (a valid genus belonging either to the order Spiriferida or to the Spiriferinida; synonym of the spiriferide Thomasaria; synonym of Squamulariina or Cyrtinaella, both spiriferinides). To address this problem we designated the specimen GSM 6915 from Wolborough quarry near Newton Abbot (Devon, England; Givetian) as the lectotype of Spirifera simplex. We examined microstructure and internal characters of a topotypic specimen and found out that Spirifera simplex has an impunctate shell and is thus a spiriferide, not a spiriferinide. No significant differences in morphology or internal characters of Thomasaria and Pyramidalia can be found, so the latter is interpreted as a junior subjective synonym of the former. The procedure used in the present analysis is equivalent to the epitypification provided for in the ICN; formalisation of a similar procedure under the ICZN is recommended.
Kazutaka Amano, Crispin T.S. Little, Kathleen A. Campbell
Three new fossil species of lucinids, Meganodontia haunuiensis, Elliptiolucina neozelandica, and Lucinoma saetheri, are described from lower to middle Miocene hydrocarbon seep carbonates from north and south of Hawke Bay, eastern North Island, New Zealand. Of these taxa Meganodontia haunuiensis is confined to seep sites south of Hawke Bay, while Elliptiolucina neozelandica comes only from the seep sites north of Hawke Bay. Using ecological information from modern bivalve species, we suggest the southern area seep sites formed in shallower waters than the northern sites. Among the lucinids, Meganodontia haunuiensis is one of the oldest records of the genus, and its distribution has shrunk from worldwide in the Miocene times to only around Taiwan today. Elliptiolucina neozelandica is the second oldest species in the genus. Since the Miocene the distribution of Elliptiolucina has narrowed but its habitat range has increased to both seeps and sandy environments, mainly around the Philippines.
M. Carolina Madozzo-Jaén, M. Encarnación Pérez, Claudia I. Montalvo
et al.
Caviidae is one of the groups of rodents with the greatest ecomorphological disparity, and with currently three known lineages: Caviinae (cuises), Dolichotinae (maras), and Hydrochoerinae (capybaras). Caviinae include small caviids represented by three extant genera (Microcavia, Cavia, and Galea) and three fossils forms (Dolicavia, Palaeocavia, and Neocavia). In Argentina, the fossil record of Caviinae is continuous and abundant since the late Miocene. Neocavia, specifically, is represented by different species recorded in the late Miocene–Pliocene. Here, we describe a new species of Neocavia from the late Miocene–early Pliocene of the Cerro Azul Formation (La Pampa Province, Argentina), and provide a re-description of already known species (Neocavia lozanoi and “Neocavia depressidens”). Also, we perform a more comprehensive review of the genus and include the Neocavia species in a phylogenetic context within Caviinae. We analyze the main patterns of the evolution of the tympanic bullae within Caviidae, and infer about a possible occasional fossorial habit of Neocavia. The morphological and phylogenetic analyses indicate that Neocavia is more closely related to Dolicavia and Microcavia than to the other Caviinae, and confirm the monophyly of the genus, with at least two clearly differentiable species. Since this study cannot confirm the systematic position and validity of “N. depressidens”, we suggest not to use this taxon as a biostratigraphic indicator.
Martín R. Ciancio, Claudia Herrera, Alejandro Aramayo
et al.
The study of Paleogene mammals of intermediate and low latitudes has increased in the last decades and has been clearly demonstrated their importance in the comprehension of the evolution and faunistic changes outside Patagonia. The study of these faunas permits establishing new comparisons among contemporaneous faunistic associations, completing the distributional patterns, and evaluating evolutionary changes in the lineages in relation to climatic conditions prevailing in each of the different regions. In this work we study the diversity of Dasypodidae recovered from the Geste Formation (Northwestern Argentina). Bearing levels of Geste Formation were referred alternatively to a Barrancan subage of Casamayoran SALMA (middle Eocene, Lutetian–Bartonian) or a Mustersan SALMA (middle–late Eocene, Bartonian–Priabonian) on faunistic comparations with their equivalent in Patagonia, although absolute isotopic data indicates ca. 37–35 Ma (late Eocene, Priabonian). We described the following taxa of Dasypodidae: (i) Dasypodinae Astegotheriini: cf. Astegotherium sp., ?Prostegotherium sp., Parastegosimpsonia cf. P. peruana; (ii) Dasypodinae indet.; (iii) Euphractinae Euphractini: Parutaetus punaensis sp. nov.; (iv) Dasypodidae incertae sedis: Pucatherium parvum, Punatherium catamarcensis gen. et sp. nov. In comparison with other beds bearing Eocene cingulate faunas from Northwestern Argentina, Geste Formation presents the greatest diversity of dasypodids. This association is consistent with a late Eocene age and shows a taxonomic and biogeographic relevant features given by a unique specific composition: (i) it differs from that known for contemporaneous faunas from Southern latitudes and younger associations from more tropical areas; (ii) it includes genera with close affinities to those distant areas; (iii) it presents unique taxa typical from Eocene units exposed at Northwestern Argentina. This highlights the evolutionary and biogeographic meaning of the cingulate of the Geste Formation and supports the idea that the faunistic regionalization probably obeyed to latitudinal than to temporal factors.
The early Eocene locality of La Borie is located in the village of Saint-Papoul, in southern France. These Eocene flu-vio-lacustrine clay deposits have yielded numerous vertebrate remains. Mammalian taxa found in the fossiliferous levels indicate an age near the reference level MP 8–9, which corresponds to the middle Ypresian, early Eocene. Here we provide a detailed description of the avian remains that were preliminarily reported in a recent study of the vertebrate fauna from La Borie. A maxilla, a quadrate, cervical vertebrae, a femur and two tibiotarsi are assigned to the giant ground bird Gastornis parisiensis (Gastornithidae). These new avian remains add to the fossil record of Gastornis, which is known from the late Paleocene to middle Eocene of Europe, early Eocene of Asia and early Eocene of North America. Gastornis parisiensis differs from the North American Gastornis giganteus in several features, including the more ventral position of the narial openings and the slender orbital process of quadrate. Two tibiotarsi and one tarsometatarsus are assigned to a new genus and species of Geranoididae, Galligeranoides boriensis gen. et sp. nov. So far, this family was known only from the early and middle Eocene of North America. The fossils from La Borie constitute the first record of the Geranoididae in Europe. We show that Gastornis coexisted with the Geranoididae in the early Eocene of both Europe (La Borie) and North America (Willwood Formation). The presence of Geranoididae and the large flightless bird Gastornis on either side of the present-day North Atlantic provides further evidence that a high-latitude land connection existed between Europe and North America in the early Eocene.