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1.
Heliyon ; 10(9): e30072, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38707322

RESUMEN

This study reconstructs the Early Pleistocene paleoenvironment of the Yuanmou Basin through coproecology of the third member of the Yuanmou Formation. We examined 38 exceptionally well-preserved coprolites from a new fossil locality, and attributed the putative defecating agent to the hypercarnivorous diet canid, Sinocuon yuanmouensis through geochemical and quantitative analyses. A new ichnogenus and ichnospecies, Cuocopros yuanmouensis igen. et. isp. nov., was established based on distinctive characteristics. Multi-disciplinary analysis, including sediment palynology and lithostratigraphy, helped primarily reconstruct a significant climatic event during the early Pleistocene, coinciding with the emergence of Yuanmou Man during the fourth member of the Yuanmou Formation's deposition. The findings provide insights into coexistence between canids, hyaenas, hominoids, and other fauna, revealing a rich paleoecosystem and food chain in the region's history. This study contributes to understanding the complex ecological dynamics during this period in the Yuanmou Basin.

2.
Int J Paleopathol ; 45: 46-54, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38657471

RESUMEN

OBJECTIVE: To analyze the presence of protozoan parasites in bird coprolites from the Tremembé Formation (Oligocene of the Taubaté Basin). MATERIALS: Twenty avian coprolites embedded in pyrobituminous shale matrices. METHODS: Samples were rehydrated and subjected to spontaneous sedimentation. RESULTS: Paleoparasitological analyses revealed oocysts compatible with the Eimeriidae family (Apicomplexa) and one single Archamoebae (Amoebozoa) cyst. CONCLUSIONS: The present work increases the amount of information about the spread of infections throughout the Cenozoic Era and reveals that the Brazilian paleoavifauna played an important role in the Apicomplexa and Amoebozoa life cycles. SIGNIFICANCE: This is the first record of protozoans in avian coprolites from the Oligocene of Brazil. These findings can help in the interpretation of phylogenies of coccidian parasites of modern birds, as certain taxonomic characters observed in the Oligocene Protozoa characterize monophyletic groups in current molecular phylogenetic analyses. LIMITATIONS: None of the oocysts were sporulated; therefore, it is not possible to identify the morphotypes to genus or species. SUGGESTIONS FOR FURTHER RESEARCH: Our results create new perspectives related to biogeographic studies of the parasitic groups described and may improve the understanding of the temporal amplitude of parasitic evolutionary relationships between Protozoans and birds.


Asunto(s)
Aves , Brasil , Animales , Fósiles , Heces/parasitología , Amebozoos/genética , Filogenia , Apicomplexa/genética , Oocistos , Paleopatología , Enfermedades de las Aves/parasitología , Enfermedades de las Aves/historia
3.
Parasitol Res ; 123(1): 112, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38270709

RESUMEN

The optimization of techniques for recovering parasitic remains is key in paleoparasitology. The Mini-FLOTAC technique (MF) is based on passive flotation and is used for diagnosis of parasites and was never tested on ancient samples. Our objective was to assess the effectiveness of MF in paleoparasitology, aiming at improving the techniques for the recovery of parasitic remains in order to upgrade the interpretative potential of the paleoparasitological evidence. Three techniques were tested: MF, spontaneous sedimentation (SS), and centrifugation-sucrose flotation (CF) testing camelid and goat coprolites. Statistical tests were performed with the R software. Our result displayed that, in the case of SAC samples, MF recovered less number of parasitic species than SS, but obtained a greater number of positive samples for protozoa. For goat samples, MF recovered a higher number of positive samples and parasitic species than SS, added that it was the technique that recovered a greater number of parasite structures. Therefore, results vary according to the zoological origin of the samples and the parasitic species recorded. We suggest starting using MF on ancient samples as a complementary method to those traditionally used in paleoparasitology. It is important to highlight that MF was a simple and faster way. The incorporation of reliable quantitative techniques opens the door to a new way of analyzing archaeological remains, deepening the study of the parasite-host relationships and its evolution through time with an epidemiological approach. Although further studies are needed, our results suggest the complementarity of these techniques in future paleoparasitological studies.


Asunto(s)
Herbivoria , Parásitos , Animales , Cabras
4.
J Helminthol ; 97: e49, 2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37345558

RESUMEN

To gain insights into the trichurid diversity in pre-Hispanic remains of South American camelids (SACs), as well as into modern SAC populations, a bibliographic search was carried out to find parasitological studies. Results showed that a total of 17 studies were performed at archaeological and paleontological sites, in which a total of 213 samples were examined. The sample set was used as the unit of analysis, and 83% of 52 pre-Hispanic sample sets were positive for parasites. Parasitological studies confirmed the pre-Hispanic presence of diverse trichurids: two Trichuris species and capillariid eggs with morphological differences that allowed them to be assigned to three different species. Currently, the richness of the native trichurid assemblages in SACs has been extended by the inclusion of two species (Trichuris sp. 2 and Capillariinae gen. sp. 1). Modern T. tenuis Chandler, 1930, considered SAC-specific, would have invaded SAC populations during the European colonization. The estimate of regional and temporal trichurid prevalence and paleoecological information allowed us to propose a possible origin for some of them. Although the present analysis is exploratory, it should stimulate future studies about the biogeographic history of SAC helminths, provide relevant information to improve descriptions of the Holocene ecology, and identify threatened helminths.


Asunto(s)
Helmintos , Nematodos , Parásitos , Animales , Trichuris , América del Sur
5.
Curr Biol ; 33(12): 2417-2424.e2, 2023 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-37230078

RESUMEN

Exceptional preservation of fossils has often been attributed to the actions of bacteria that aid in the preservation of soft tissues that normally decay rapidly. However, it is well known that fungi play a major role in organic matter decomposition, biogeochemical cycling of elements, and metal-mineral transformations in modern ecosystems. Although the fungal fossil record can be traced back over a billion years, there are only a few recorded examples of fungal roles in fossilization. In this research, we have carried out a detailed geobiological investigation on early Pleistocene hyena coprolites (fossilized dung) in an attempt to ascertain possible fungal involvement in their formation. Using an advanced microscopic and mineralogical approach, we found that numerous hydroxyapatite nanofibers (25-34 nm on average), interwoven to form spheroidal structures, constituted the matrix of the coprolites in addition to food remains. These structures were found to be extremely similar in texture and mineral composition to biominerals produced during laboratory culture of a common saprophytic and geoactive fungus, Aspergillus niger, in the presence of a solid source of calcium (Ca) and phosphorus (P). This observation, and our other data obtained, strongly suggests that fungal metabolism can provide a mechanism that can result in fossil biomineralization, and we hypothesize, therefore, that this may have contributed to the formation of well-preserved fossils (Lagerstätten) in the geological record. The characteristic polycrystalline nanofibers may also have served as a potential biosignature for fungal life in early Earth and extraterrestrial environments.


Asunto(s)
Biomineralización , Fósiles , Ecosistema , Bacterias , Minerales
6.
Biology (Basel) ; 11(9)2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-36138768

RESUMEN

The reconstruction of ancient trophic networks is pivotal to our understanding of ecosystem function and change through time. However, inferring dietary relationships in enigmatic ecosystems dominated by organisms without modern analogues, such as the Carboniferous Mazon Creek fauna, has previously been considered challenging: preserved coprolites often do not retain sufficient morphology to identify the dietary composition. Here, we analysed n = 3 Mazon Creek coprolites in concretions for dietary signals in preserved biomarkers, stable carbon isotope data, and macromolecular composition. Cholesteroids, metazoan markers of cholesterol, show an increased abundance in the sampled coprolites (86 to 99% of the total steranes) compared to the surrounding sediment, indicating an endogenous nature of preserved organics. Presence of unaltered 5α-cholestan-3ß-ol and coprostanol underline the exceptional molecular preservation of the coprolites, and reveal a carnivorous diet for the coprolite producer. Statistical analyses of in situ Raman spectra targeting coprolite carbonaceous remains support a metazoan affinity of the digested fossil remains, and suggest a high trophic level for the coprolite producer. These currently oldest, intact dietary stanols, combined with exquisitely preserved macromolecular biosignatures in Carboniferous fossils offer a novel source of trophic information. Molecular and biosignature preservation is facilitated by rapid sedimentary encapsulation of the coprolites within days to months after egestion.

7.
Parasitology ; 149(12): 1556-1564, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35924600

RESUMEN

The aim of this research was to analyse the variability of parasite assemblages on a small spatial scale, by examining carnivore coprolites from the archaeological site Campo Moncada 2 (CM2), Piedra Parada area, Chubut province, Argentina, and comparing the results with those previously obtained from the archaeological site Campo Cerda 1 (CCe1), located in the same area. Six carnivore coprolites from CM2 were analysed: 4 obtained in sub-level 2a and 2 obtained in sub-level 2a/b. Two radiocarbon dates associated with the coprolites placed the samples chronologically between 780 ± 80 and 860 ± 80 years before present. The rehydrated sediments were sieved and then allowed to sediment spontaneously. The sediment was used for parasitological examination under light microscopy. Conservative estimation of total parasite richness resulted in 21 parasitic taxa. The taxa with the highest fecal prevalence (>50%) corresponded to parasites prevalent in modern carnivores (Alaria sp., Toxocara cf. canis, Toxascaris sp., Eucoleus cf. aerophila, Trichuris sp. and Ancylostomatidae gen. sp.). Assuming that the fox coprolites are contemporaneous, the total fecal parasite richness estimated for CM2 and previously for CCe1 was similar. The high total parasite richness found suggests a network of host­parasite relationships that could include regional hunter-gatherers. The results obtained in carnivore coprolites allow us to infer a very diverse biological community in Piedra Parada area, so the regional caves and rockshelters could have a proportional epidemiological importance as parasite exchange nodes.


Asunto(s)
Carnívoros , Parásitos , Piedra , Animales , Paleopatología , Argentina/epidemiología , Fósiles , Heces/parasitología
8.
PeerJ ; 10: e13652, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35811823

RESUMEN

Excrement-shaped ferruginous masses have been recovered from the Miocene of Turów mine in south-western Poland. These siderite masses have been the subject of much controversy, having been interpreted either as being coprolites, cololithes or pseudofossils created by mechanical deformation of plastic sediment. Here we present the results of mineralogical, geochemical, petrographic and microtomographical analyses. Our data indicate that these masses consist of siderite and iron oxide rather than phosphate, and rarely contain recognizable food residues, which may suggest abiotic origins of these structures. On the other hand, evidence in support of a fecal origin include: (i) the presence of two distinct morphotypes differing in size and shape, (ii) the presence of rare hair-like structures or coalified inclusions and (iii) the presence of rare fine striations on the surface. Importantly, comparative actualistic study of recent vertebrate feces shows overall resemblance of the first morphotype (sausage-shaped with rare coalified debris) to excrements of testudinoid turtles (Testudinoidea), whose shell fragment was found in the investigated locality. The second morphotype (rounded to oval-shaped with hair-like structures), in turn, is similar to the feces of some snakes (Serpentes), the remains of which were noted in the Miocene of the neighborhood areas. Other potential producers (such as lizards and crocodiles) and even abiotic origins cannot be fully excluded but are less likely.


Asunto(s)
Fósiles , Lagartos , Animales , Polonia , Lagartos/anatomía & histología , Serpientes
9.
Dokl Biol Sci ; 504(1): 82-84, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35821300

RESUMEN

Coprolites of the hyena Pachycrocuta brevirostris from the Lower Pleistocene (Upper Villafranchian) of Taurida Cave (Crimea) were studied. One of the three hyena coprolites contained helminth eggs. These eggs were assigned to Toxocara sp. based on their size and morphology. Toxocariasis was evidently a very common infestation among extinct hyena species. The find of toxocara in P. brevirostris coprolite from the Taurida Cave is the earliest evidence of roundworm infestation in P. brevirostris.


Asunto(s)
Hyaenidae , Toxocara , Animales , Cuevas , Fósiles
10.
Bioinformation ; 18(12): 1159-1165, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37701514

RESUMEN

We analyzed human coprolites from the Sacred City of Caral, the oldest civilization in America (3000- and 1800-years BC). Our objective was to know the microbial diversity of the Caral Civilization through the use of a mobile ancient laboratory. DNA extraction conducted in a mobile laboratory placed near the collection site to reduce exposure of samples to contaminants and favor a rapid molecular processing. Using 16S rRNA and ITS 1 amplicon sequencing, we have elaborated the first list of the microbiomes of Caral, based on the bacterial and fungal community fingerprints detected in the coprolites recovered in six sectors of that ancient urban center. Among the most abundant sequences were those associated with Firmicutes for bacteria, Ascomycota and Basidiomycota for fungi. Bacillus was the most abundant bacterial genera in all samples analyzed, compromising up to 24.81% of the total bacterial abundance; while Aspergillus (11.43%) was the most abundant genera among fungal communities.

11.
Bioinformation ; 18(12): 1114-1118, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37701515

RESUMEN

We report the use of a mobile laboratory set up to extract ancient DNA (aDNA) from 34 human coprolites (fossilized faeces) samples. Our approach enabled the rapid genetic characterization of 5,000 years old archeological samples. It is useful for the on-site screening of museums and freshly excavated samples for DNA. This approach is accessible to other investigators as the mobile laboratory was set up using commercially available instruments.

12.
Naturwissenschaften ; 108(5): 36, 2021 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-34432151

RESUMEN

Spiraxis interstrialis, and its junior synonym Fayolia mourloni, an uppermost Famennian (Upper Devonian) fossil first described as algae and subsequently interpreted as the oldest known chondrichthyan egg case, is reinvestigated based on the discovery of several additional specimens in Belgian collections. New data, in particular from micro-CT imaging, allow to refute S. interstrialis, and by extension also Spiraxis major (the type species of Spiraxis Newberry, non Adams) and Spiraxis randalli from the Famennian of New York and Pennsylvania, as chondrichthyan egg cases. Alternative interpretations of these enigmatic helicoidal fossils are discussed. The first occurrence of oviparity in the fossil record of chondrichthyans is thus not as old as previously thought and is close to the first occurrence of viviparity in this group, both being recognised now in the Mississippian. The question of which of both conditions is plesiomorphic within chondrichthyans, and more widely within vertebrates, is discussed. Also, the presence of the genus Spiraxis in both the USA (east coast) and Belgium reinforces the strong faunal resemblance already observed in both palaeogeographical areas. It suggests important faunal exchanges between these regions of the Euramerica landmass during the Famennian.


Asunto(s)
Evolución Biológica , Fósiles , Animales , Reproducción , Vertebrados , Microtomografía por Rayos X
13.
Curr Biol ; 31(15): 3374-3381.e5, 2021 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-34197727

RESUMEN

The Triassic was a crucial period for the early evolution and diversification of insects, including Coleoptera1-3-the most diverse order of organisms on Earth. The study of Triassic beetles, however, relies almost exclusively on flattened fossils with limited character preservation. Using synchrotron microtomography, we investigated a fragmentary Upper Triassic coprolite, which contains a rich record of 3D-preserved minute beetle remains of Triamyxa coprolithica gen. et sp. nov. Some specimens are nearly complete, preserving delicate structures of the legs and antennae. Most of them are congruent morphologically, implying that they are conspecific. Phylogenetic analyses suggest that T. coprolithica is a member of Myxophaga, a small suborder of beetles with a sparse fossil record, and that it represents the only member of the extinct family Triamyxidae fam. nov. Our findings highlight that coprolites can contain insect remains, which are almost as well preserved as in amber. They are thus an important source of information for exploring insect evolution before the Cretaceous-Neogene "amber time window." Treated as food residues, insect remains preserved in coprolites also have important implications for the paleoecology of insectivores, in this case, likely the dinosauriform Silesaurus opolensis.


Asunto(s)
Ámbar , Escarabajos , Fósiles , Animales , Escarabajos/genética , Filogenia
14.
Philos Trans R Soc Lond B Biol Sci ; 375(1812): 20190577, 2020 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-33012224

RESUMEN

In this study, I use microbiome datasets from global soil samples and diverse hosts to learn whether soil microbial taxa are found in host microbiomes, and whether these observations fit the narrative that environmental interaction influences human microbiomes. A major motivation for conducting host-associated microbiome research is to contribute towards understanding how the environment may influence host physiology. The microbial molecular network is considered a key vector by which environmental traits may be transmitted to the host. Research on human evolution seeks evidence that can inform about the living experiences of human ancestors. This objective is substantially enhanced by recent work on ancient biomolecules from preserved microbial tissues, such as dental calculus, faecal sediments and whole coprolites. A challenge yet is to distinguish authentic biomolecules from environmental contaminants deposited contemporaneously, primarily from soil. However, we do not have sound expectations about the soil microbial elements arriving to host-associated microbiomes in a modern context. One assumption in human microbiome research is that proximity to the natural environment should affect biodiversity or impart genetic elements. I present evidence supporting the assumption that environmental soil taxa are found among host-associated gut taxa, which can recapitulate the surrounding host habitat ecotype. Soil taxa found in gut microbiomes relate to a set of universal 'core' taxa for all soil ecotypes, demonstrating that widespread host organisms may experience a consistent pattern of external environmental cues, perhaps critical for development. Observed differentiation of soil feature diversity, abundance and composition among human communities, great apes and invertebrate hosts also indicates that lifestyle patterns are inferable from an environmental signal that is retrievable from gut microbiome amplicon data. This article is part of the theme issue 'Insights into health and disease from ancient biomolecules'.


Asunto(s)
ADN Bacteriano/análisis , Microbiota , Microbiología del Suelo , Humanos
15.
Philos Trans R Soc Lond B Biol Sci ; 375(1812): 20190586, 2020 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-33012230

RESUMEN

Human microbiome studies are increasingly incorporating macroecological approaches, such as community assembly, network analysis and functional redundancy to more fully characterize the microbiome. Such analyses have not been applied to ancient human microbiomes, preventing insights into human microbiome evolution. We address this issue by analysing published ancient microbiome datasets: coprolites from Rio Zape (n = 7; 700 CE Mexico) and historic dental calculus (n = 44; 1770-1855 CE, UK), as well as two novel dental calculus datasets: Maya (n = 7; 170 BCE-885 CE, Belize) and Nuragic Sardinians (n = 11; 1400-850 BCE, Italy). Periodontitis-associated bacteria (Treponema denticola, Fusobacterium nucleatum and Eubacterium saphenum) were identified as keystone taxa in the dental calculus datasets. Coprolite keystone taxa included known short-chain fatty acid producers (Eubacterium biforme, Phascolarctobacterium succinatutens) and potentially disease-associated bacteria (Escherichia, Brachyspira). Overlap in ecological profiles between ancient and modern microbiomes was indicated by similarity in functional response diversity profiles between contemporary hunter-gatherers and ancient coprolites, as well as parallels between ancient Maya, historic UK, and modern Spanish dental calculus; however, the ancient Nuragic dental calculus shows a distinct ecological structure. We detected key ecological signatures from ancient microbiome data, paving the way to expand understanding of human microbiome evolution. This article is part of the theme issue 'Insights into health and disease from ancient biomolecules'.


Asunto(s)
Bacterias/aislamiento & purificación , ADN Antiguo/análisis , Cálculos Dentales/historia , Heces/microbiología , Microbiota , Arqueología , Belice , ADN Bacteriano/análisis , Cálculos Dentales/microbiología , Secuenciación de Nucleótidos de Alto Rendimiento , Historia Antigua , Historia Medieval , Humanos , Italia , México
16.
Parasitol Int ; 78: 102147, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32442497

RESUMEN

Parasite remains in micromammal fecal pellets collected from the paleontological site "Cueva Peligro" (CP 43°40'18"S, 66°24'52"W), Chubut Province, Argentina, were examined. The samples were obtained from two grids, dated between 1220 ± 7014C yr B.P. to modern dates. Fecal pellets were whole processed, rehydrated, homogenized, and examined via light microscopy. Eggs of parasites found were measured and photographed. Fecal pellets belong to one or more insectivore to omnivore unidentified micromammal species, possibly sigmodontine rodents. A high number of helminthes species was recorded (11 species), eight nematodes, two anoplocephalid cestodes and one acanthocephalan species. The sigmodontine-parasite relationship varied throughout the studied period and between studied grids. This is the first time that Gongylonema sp. and Syphacia sp. are reported from ancient times from Patagonia. The obtained results contribute to the knowledge of parasite assemblages associated to native South American sigmodontine rodents and the zoonoses present in the area throughout the lasts 1200 years.


Asunto(s)
Acantocéfalos/aislamiento & purificación , Cestodos/aislamiento & purificación , Heces/parasitología , Nematodos/aislamiento & purificación , Sigmodontinae/parasitología , Distribución Animal , Animales , Argentina , Cuevas , Fósiles/parasitología
17.
World J Gastroenterol ; 25(42): 6289-6298, 2019 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-31754290

RESUMEN

The bacterium Helicobacter pylori (H. pylori) infects the stomachs of approximately 50% of all humans. With its universal occurrence, high infectivity and virulence properties it is considered as one of the most severe global burdens of modern humankind. It has accompanied humans for many thousands of years, and due to its high genetic variability and vertical transmission, its population genetics reflects the history of human migrations. However, especially complex demographic events such as the colonisation of Europe cannot be resolved with population genetic analysis of modern H. pylori strains alone. This is best exemplified with the reconstruction of the 5300-year-old H. pylori genome of the Iceman, a European Copper Age mummy. Our analysis provided precious insights into the ancestry and evolution of the pathogen and underlined the high complexity of ancient European population history. In this review we will provide an overview on the molecular analysis of H. pylori in mummified human remains that were done so far and we will outline methodological advancements in the field of ancient DNA research that support the reconstruction and authentication of ancient H. pylori genome sequences.


Asunto(s)
Restos Mortales/microbiología , ADN Antiguo/análisis , Infecciones por Helicobacter/microbiología , Momias , ADN Bacteriano/análisis , Genoma Bacteriano , Helicobacter pylori/aislamiento & purificación , Humanos , Estómago/microbiología , Virulencia
18.
PeerJ ; 7: e7375, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31523493

RESUMEN

Diets of pterosaurs have mainly been inferred from indirect evidence such as comparative anatomy, associations of co-occurring fossils, and functional morphology. Gut contents are rare, and until now there is only a single coprolite (fossil dropping), with unidentified inclusions, known. Here we describe three coprolites collected from a palaeosurface with numerous pterosaur tracks found in early Kimmeridgian (Hypselocyclum Zone) intertidal deposits of the Wierzbica Quarry, Poland. The specimens' morphology and association to the tracks suggest a pterosaur producer. Synchrotron scans reveal numerous small inclusions, with foraminifera making up the majority of the identifiable ones. Other small remains include shells/carapaces (of bivalves, ostracods, and other crustaceans/arthropods) and bristles (some possibly of polychaete worms). The high density of the small shelly inclusions suggest that they were not accidently ingested, but constituted an important food source for the pterosaur(s), perhaps together with unpreserved soft-bodied animals. The combined evidence from the tracks and coprolites suggest a filter-feeding ctenochasmatid as the most likely tracemaker. If true, this significantly expands the bromalite record for this pterosaur group, which was previously only known from gastroliths. Moreover, this study also provides the first direct evidence of filter feeding in Jurassic pterosaurs and shows that they had a similar diet to the recent Chilean flamingo (Phoenicopterus chilensis).

19.
Parasitol Int ; 72: 101947, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31233826

RESUMEN

Two new ascaridoid species, Bauruascaris cretacicus n. gen. et n. sp., and Bauruascaris adamantinensis n. gen. et n. sp., are described based on the fossils of eggs preserved in 80-70 million year old phosphatized coprolites of Crocodyliformes, chronologically assigned to the Upper Cretaceous (Campanian/Maastrichtian age), collected from sedimentary rocks of the Bauru Group, Adamantina Formation in the municipality of Santo Anastácio, in the southwestern region of the state of São Paulo, Brazil, South America. This paper describes the oldest ascaridoid species ever recorded in Crocodylomorpha. Hence, this article contributes to the body of knowledge about the evolutionary history of this nematode group. It also offers a clue about the composition of the parasite fauna of these reptiles from the Late Cretaceous, which is still unknown despite numerous studies about various aspects of their biology and the pioneering paleoparasitological analysis of animal coprolites by South American researchers.


Asunto(s)
Caimanes y Cocodrilos/parasitología , Ascaridia/clasificación , Evolución Biológica , Fósiles/parasitología , Animales , Brasil , Óvulo/clasificación , Filogenia
20.
R Soc Open Sci ; 6(3): 181042, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31031991

RESUMEN

Diets of extinct animals can be difficult to analyse if no direct evidence, such as gut contents, is preserved in association with body fossils. Inclusions from coprolites (fossil faeces), however, may also reflect the diet of the host animal and become especially informative if the coprolite producer link can be established. Here we describe, based on propagation phase-contrast synchrotron microtomography (PPC-SRµCT), the contents of five morphologically similar coprolites collected from two fossil-bearing intervals from the highly fossiliferous Upper Triassic locality at Krasiejów in Silesia, Poland. Beetle remains, mostly elytra, and unidentified exoskeleton fragments of arthropods are the most conspicuous inclusions found in the coprolites. The abundance of these inclusions suggests that the coprolite producer deliberately targeted beetles and similar small terrestrial invertebrates as prey, but the relatively large size of the coprolites shows that it was not itself a small animal. The best candidate from the body fossil record of the locality is the dinosauriform Silesaurus opolensis Dzik, 2003, which had an anatomy in several ways similar to those of bird-like neotheropod dinosaurs and modern birds. We hypothesize that the beak-like jaws of S. opolensis were used to efficiently peck small insects off the ground, a feeding behaviour analogous to some extant birds.

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