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1.
Environ Pollut ; 355: 124089, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38729508

RESUMO

Glacial bodies in the Peruvian Andes Mountains store and supply freshwater to hundreds of thousands of people in central Peru. Atmospheric black carbon (BC) is known to accelerate melting of snow and ice, in addition to contributing to air pollution and the health of people. Currently there is limited understanding on the sources and temporal variability of BC in valley and mountain environments in Peru. To address this problem, this study combined surface observations of BC collected during 2022-2023 with WRF model simulations and HYSPLIT trajectories to analyze the dispersion and sources of BC in valley and high elevation environments and the associated local atmospheric circulations. Results show high BC concentrations are associated with the valley-mountain wind system that occurs on both sides of the Huaytapallana mountain range. A pronounced circulation occurs on the western slopes of Huaytapallana when concentrations of BC increase during daylight hours, which transports atmospheric pollutants from cities in the Mantaro River Valley to the Huaytapallana mountain range. Low concentrations of BC are associated with circulations from the east that are channeled by the pronounced ravines of the Andes-Amazon transition. On average, during the season of highest BC concentrations (July-November), the relative contributions of fossil fuels are dominant to biomass burning at the valley observatory and are slightly lower at the Huaytapallana observatory. These results demonstrate the need to promote mitigation actions to reduce emissions of BC and air pollution associated with forest fires and local anthropogenic activity.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Atmosfera , Monitoramento Ambiental , Fuligem , Peru , Poluentes Atmosféricos/análise , Fuligem/análise , Atmosfera/química , Poluição do Ar/estatística & dados numéricos
2.
Curr Biol ; 34(12): 2712-2718.e3, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38806055

RESUMO

New World porcupines (Erethizontinae) originated in South America and dispersed into North America as part of the Great American Biotic Interchange (GABI) 3-4 million years ago.1 Extant prehensile-tailed porcupines (Coendou) today live in tropical forests of Central and South America.2,3 In contrast, North American porcupines (Erethizon dorsatum) are thought to be ecologically adapted to higher-latitude temperate forests, with a larger body, shorter tail, and diet that includes bark.4,5,6,7 Limited fossils8,9,10,11,12,13 have hindered our understanding of the timing of this ecological differentiation relative to intercontinental dispersal during the GABI and expansion into temperate habitats.14,15,16,17,18 Here, we describe functionally important features of the skeleton of the extinct Erethizon poyeri, the oldest nearly complete porcupine skeleton documented from North America, found in the early Pleistocene of Florida. It differs from extant E. dorsatum in having a long, prehensile tail, grasping foot, and lacking dental specializations for bark gnawing, similar to tropical Coendou. Results from phylogenetic analysis suggest that the more arboreal characteristics found in E. poyeri are ancestral for erethizontines. Only after it expanded into temperate, Nearctic habitats did Erethizon acquire the characteristic features that it is known for today. When combined with molecular estimates of divergence times, results suggest that Erethizon was ecologically similar to a larger species of Coendou when it crossed the Isthmus of Panama by the early Pleistocene. It is likely that the range of this more tropically adapted form was limited to a continuous forested biome that extended from South America through the Gulf Coast.


Assuntos
Fósseis , Porcos-Espinhos , Porcos-Espinhos/anatomia & histologia , Animais , Fósseis/anatomia & histologia , América do Sul , Cauda/anatomia & histologia , Extinção Biológica , América do Norte , Evolução Biológica , Ecossistema
3.
Proc Biol Sci ; 291(2021): 20240262, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38654646

RESUMO

The fossil fish Ptychodus Agassiz, 1834, characterized by a highly distinctive grinding dentition and an estimated gigantic body size (up to around 10 m), has remained one of the most enigmatic extinct elasmobranchs (i.e. sharks, skates and rays) for nearly two centuries. This widespread Cretaceous taxon is common in Albian to Campanian deposits from almost all continents. However, specimens mostly consist of isolated teeth or more or less complete dentitions, whereas cranial and post-cranial skeletal elements are very rare. Here we describe newly discovered material from the early Late Cretaceous of Mexico, including complete articulated specimens with preserved body outline, which reveals crucial information on the anatomy and systematic position of Ptychodus. Our phylogenetic and ecomorphological analyses indicate that ptychodontids were high-speed (tachypelagic) durophagous lamniforms (mackerel sharks), which occupied a specialized predatory niche previously unknown in fossil and extant elasmobranchs. Our results support the view that lamniforms were ecomorphologically highly diverse and represented the dominant group of sharks in Cretaceous marine ecosystems. Ptychodus may have fed predominantly on nektonic hard-shelled prey items such as ammonites and sea turtles rather than on benthic invertebrates, and its extinction during the Campanian, well before the end-Cretaceous crisis, might have been related to competition with emerging blunt-toothed globidensine and prognathodontine mosasaurs.


Assuntos
Fósseis , Filogenia , Tubarões , Animais , Fósseis/anatomia & histologia , México , Tubarões/anatomia & histologia , Tubarões/classificação , Tubarões/fisiologia , Evolução Biológica , Dente/anatomia & histologia
4.
Environ Monit Assess ; 196(5): 481, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38683240

RESUMO

The continuous expansion of the global vehicle fleet poses a growing threat to environmental quality through heavy metal contamination. In this scenario, monitoring to safeguard public health in urban areas is necessary. Our study involved the collection of 36 street dust and 29 moss samples from roads of a Brazilian metropolis (Recife) with varying traffic intensities as follows: natural reserve (0 vehicles per day), low (< 15,000 vehicles per day), medium (15,000-30,000 vehicles per day), and high (> 30,000 vehicles per day). ICP-AES analysis was performed to determine the concentrations of nine potentially toxic metals (Ba, Cd, Cr, Cu, Mn, Ni, Pb, V, and Zn) to assess the influence of vehicular flow on urban contamination. In the street dust samples, the mean metal concentrations (mg kg-1) exhibited the following order: Ba (503.7) > Mn (303.0) > Zn (144.4) > Cu (95.3) > Cr (56.1) > Pb (34.2) > V (28.7) > Ni (11.3) > Cd (1.5). Conversely, in the moss samples, the metal concentration order was as follows (mg kg-1): Mn (63.8) > Zn (62.5) > Ba (61.0) > Cu (17.7) > Cr (8.0) > V (7.3) > Pb (7.0) > Ni (2.9) > Cd (0.3). Roads with higher traffic volumes exhibited the highest metal enrichments in moss samples for all metals and in dust samples for Cd, Cr, Mn, Ni, and V. However, dust from low-flow roads had higher enrichments for Ba, Cu, and Zn, indicating the influential role of other traffic-related factors in metal deposition. Our findings highlight traffic flow as the predominant source of pollution in urban centers, with both street dust and moss serving as sensitive indicators of metal input attributable to vehicular traffic. These indicators offer valuable insights for urban quality monitoring and pollution control efforts.


Assuntos
Cidades , Poeira , Monitoramento Ambiental , Metais Pesados , Metais Pesados/análise , Brasil , Monitoramento Ambiental/métodos , Poeira/análise , Poluentes Ambientais/análise , Emissões de Veículos/análise , Poluentes Atmosféricos/análise
5.
Environ Pollut ; 346: 123568, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38382732

RESUMO

Current methods for measuring black carbon aerosol (BC) by optical methods apportion BC to fossil fuel and wood combustion. However, these results are aggregated: local and non-local combustion sources are lumped together. The spatial apportioning of carbonaceous aerosol sources is challenging in remote or suburban areas because non-local sources may be significant. Air quality modeling would require highly accurate emission inventories and unbiased dispersion models to quantify such apportionment. We propose FUSTA (FUzzy SpatioTemporal Apportionment) methodology for analyzing aethalometer results for equivalent black carbon coming from fossil fuel (eBCff) and wood combustion (eBCwb). We applied this methodology to ambient measurements at three suburban sites around Santiago, Chile, in the winter season 2021. FUSTA results showed that local sources contributed ∼80% to eBCff and eBCwb in all sites. By using PM2.5 - eBCff and PM2.5 - eBCwb scatterplots for each fuzzy cluster (or source) found by FUSTA, the estimated lower edge lines showed distinctive slopes in each measurement site. These slopes were larger for non-local sources (aged aerosols) than for local ones (fresh emissions) and were used to apportion combustion PM2.5 in each site. In sites Colina, Melipilla and San Jose de Maipo, fossil fuel combustion contributions to PM2.5 were 26 % (15.9 µg m-3), 22 % (9.9 µg m-3), and 22 % (7.8 µg m-3), respectively. Wood burning contributions to PM2.5 were 22 % (13.4 µg m-3), 19 % (8.9 µg m-3) and 22% (7.3 µg m-3), respectively. This methodology generates a joint source apportionment of eBC and PM2.5, which is consistent with available chemical speciation data for PM2.5 in Santiago.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Material Particulado/análise , Monitoramento Ambiental/métodos , Estações do Ano , Fuligem/análise , Combustíveis Fósseis/análise , Aerossóis/análise , Carbono/análise
6.
Anat Rec (Hoboken) ; 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37779325

RESUMO

Four extant species of anhingids are found worldwide, all belonging to a single genus (Anhinga). However, the fossil record reveals a much greater diversity of this group in the past. The oldest known anhingids date back to the upper Oligocene period in Australia, but during the Miocene epoch in South America, they achieved their most remarkable diversity. This study describes newly discovered anhingid fossils from the Late Miocene period in South America. These fossils were extracted from the Acre conglomerate member, part of the Upper Miocene deposits in the southwestern Amazon region. The described fossils consist of two fragments of pelvic girdles, two femora, and two vertebrae belonging to a giant anhingid (Macranhinga sp.), as well as a vertebra from Anhinga minuta, the smallest of all darters. The examination of these fossils suggests the presence of potentially three distinct anhingid taxa within the same locality. The environment in which the conglomerate deposits were formed was ecologically complex. It is likely that these three species coexisted within the same ecosystem but avoided direct competition for food and reproductive sites by not fully exploiting their fundamental niche.

7.
Am J Bot ; 110(10): e16231, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37661813

RESUMO

PREMISE: Alismataceae, a sub-cosmopolitan family with ca. 17 genera and 113 species, is a large group of aquatic plants. Compression/impressions and bioinclusions of reproductive parts in amber support the documentation of the lineage in low-latitude North America. In Mexico, fossil aquatic plants have been infrequently documented. The new reproductive structures exhibit characteristics of Alismataceae, whose fossil record is mainly documented in the northern hemisphere through of fruits and seeds. METHODS: We described and compared 150 samples of reproductive structures preserved as impressions/compressions from the Oligocene Los Ahuehuetes locality in the state of Puebla, and two bioinclusions from the Miocene amber of Simojovel de Allende in the state of Chiapas, Mexico with extinct and extant taxa. Using a parsimony analysis based on 29 floral characters of 17 extant genera of the Alismataceae, we evaluated the relationship between the fossil material and potential living relatives. RESULTS: We discovered a new genus Nichima based on a perfect, actinomorphic flower with an expanded receptacle, three persistent sepals with multiple vasculatures, delicate and caducous petals, six stamens, and a gynoecium composed of three to more superior carpels, maturing into achenes. These characteristics resemble flowers of Alismataceae. Nichima represents an extinct member of the family, with two new species described here, Nichima magalloniae L. Hern., Cevallos-Ferriz et Hernández-Damián sp. nov. and Nichima gonzalez-medranoi L. Hern., Cevallos-Ferriz et Hernández-Damián, sp. nov. Their phylogenetic position suggests affinity with a clade that includes Baldiella, Echinodorus, and Alisma. CONCLUSIONS: Reproductive structures from the Cenozoic of Mexico support the identification of a new extinct genus, Nichima, evidencing the extensive history of Alismataceae in North America's low latitudes and suggesting a southern extension of the boreotropical flora.


Assuntos
Alismataceae , Filogenia , México , Âmbar , Flores , Fósseis
8.
Artigo em Inglês | MEDLINE | ID: mdl-37593207

RESUMO

This synoptic review aims to bring some general information on fossil scorpions, namely those trapped in amber - fossilized resin - ranging from Lower Cretaceous through the Palaeocene and up to the Miocene. The question to be addressed is how the study of these fossils can be connected with possible present scorpionism problems. A precise knowledge of these ancient lineages provides information about the evolution of extant lineages, including the buthoids, which contain most known noxious species. Among the Arthropods found trapped in amber, scorpions are considered rare. A limited number of elements have been described from the Late Tertiary Dominican and Mexican amber, while the most ancient Tertiary amber from the Baltic region produced more consistent results in the last 30 years, primarily focusing on a single limited lineage. Contrarily, the Cretaceous amber from Myanmar, also called Burmite, has yielded and continues to yield a significant number of results represented by several distinct lineages, which attest to the considerable degree of diversity that existed in the Burmese amber-producing forests. As in my previous similar contributions to this journal, the content of this note is primarily addressed to non-specialists whose research embraces scorpions in various fields such as venom toxins and public health. An overview knowledge of at least some fossil lineages can eventually help to clarify why some extant elements associated with the buthoids represent dangerous species while others are not noxious.

9.
J Morphol ; 284(6): e21588, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37183492

RESUMO

Penguins (Aves, Sphenisciformes) are pursuit divers that feed mainly on krill, fish, and squid. Although they are opportunistic feeders, some species are more generalists than others and many show dietary preferences toward krill and other crustaceans or fish and squid. Their diving depth seems to follow a body size pattern and relates to the type of item that they prey on. Penguins dive with their wing; hence their wing musculature is responsible for the animal maneuverability and strength while diving. In the present study, ecological traits such as diving depths and prey composition are used to explore if morphology relates to foraging habits. A geometric morphometric approach is used to quantitatively address these morphological differences in the wing apparatus of all extant penguins and a fossil species taking into consideration allometric and phylogenetic factors. Results show that morphological differences among penguins with different diets are significant and strong; groups are well separated with the greatest differences found between piscivorous and crustacivorous penguins. Dive depth has a moderate covariation with morphology and a strong correspondence with wing area. Last, Madrynornis mirandus, an exceptionally well-preserved fossil from the Miocene of Patagonia, is found to be close to the piscivorous and generalist piscivorous species. It is proposed that swimming styles correlate with specific traits of the anatomy of wing and pectoral girdle skeleton and muscles.


Assuntos
Mergulho , Spheniscidae , Animais , Spheniscidae/anatomia & histologia , Filogenia , Mergulho/fisiologia , Natação/fisiologia , Asas de Animais/fisiologia
10.
Ann Bot ; 131(7): 1133-1147, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37208295

RESUMO

BACKGROUND AND AIMS: The genus Buxus has high levels of endemism in the Caribbean flora, with ~50 taxa. In Cuba, 82 % grow on ultramafic substrates and 59 % are nickel (Ni) accumulators or Ni hyperaccumulators. Hence it is an ideal model group to study if this diversification could be related to adaptation to ultramafic substrates and to Ni hyperaccumulation. METHODS: We generated a well-resolved molecular phylogeny, including nearly all of the Neotropical and Caribbean Buxus taxa. To obtain robust divergence times we tested for the effects of different calibration scenarios, and we reconstructed ancestral areas and ancestral character states. Phylogenetic trees were examined for trait-independent shifts in diversification rates and we used multi-state models to test for state-dependent speciation and extinction rates. Storms could have contributed to Cuba acting as a species pump and to Buxus reaching other Caribbean islands and northern South America'. KEY RESULTS: We found a Caribbean Buxus clade with Mexican ancestors, encompassing three major subclades, which started to radiate during the middle Miocene (13.25 Mya). Other Caribbean islands and northern South America were reached from ~3 Mya onwards. CONCLUSIONS: An evolutionary scenario is evident in which Buxus plants able to grow on ultramafic substrates by exaptation became ultramafic substrate endemics and evolved stepwise from Ni tolerance through Ni accumulation to Ni hyperaccumulation, which has triggered species diversification of Buxus in Cuba. Storms could have contributed to Cuba acting as a species pump and to Buxus reaching other Caribbean islands and northern South America'.


Assuntos
Buxus , Níquel , Filogenia , Cuba , Ilhas , Região do Caribe , Índias Ocidentais , Especiação Genética
11.
Mol Phylogenet Evol ; 183: 107773, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36977459

RESUMO

Although a consensus exists that all living turtles fall within either Pleurodira or Cryptodira clades, estimating when these lineages split is still under debate. Most molecular studies date the split in the Triassic Period, whereas a Jurassic age is unanimous among morphological studies. Each hypothesis implies different paleobiogeographical scenarios to explain early turtle evolution. Here we explored the rich turtle fossil record with the Fossilized Birth-Death (FBD) and the traditional node dating (ND) methods using complete mitochondrial genomes (147 taxa) and a set of nuclear orthologs with over 10 million bp (25 taxa) to date the major splits in Testudines. Our results support an Early Jurassic split (191-182 Ma) for the crown Testudines with great consistency across different dating methods and datasets, with a narrow confidence interval. This result is independently supported by the oldest fossils of Testudines that postdate the Middle Jurassic (174 Ma), which were not used for calibration in this study. This age coincides with the Pangaea fragmentation and the formation of saltwater barriers such as the Atlantic Ocean and the Turgai Strait, supporting that diversification in Testudines was triggered by vicariance. Our ages of the splits in Pleurodira coincide with the geologic events of the Late Jurassic and Early Cretaceous. Conversely, the early Cryptodira radiation remained in Laurasia, and its diversification ensued as all its major lineages expanded their distribution into every continent during the Cenozoic. We provide the first detailed hypothesis of the evolution of Cryptodira in the Southern Hemisphere, in which our time estimates are correlated with each contact between landmasses derived from Gondwana and Laurasia. Although most South American Cryptodira arrived through the Great American Biotic Interchange, our results indicate that the Chelonoidis ancestor probably arrived from Africa through the chain islands of the South Atlantic during the Paleogene. Together, the presence of ancient turtle diversity and the vital role that turtles occupy in marine and terrestrial ecosystems underline South America as a chief area for conservation.


Assuntos
Fósseis , Tartarugas , Animais , Filogenia , Ecossistema , América do Sul
12.
New Phytol ; 238(6): 2685-2697, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36960534

RESUMO

Fossil discoveries can transform our understanding of plant diversification over time and space. Recently described fossils in many plant families have pushed their known records farther back in time, pointing to alternative scenarios for their origin and spread. Here, we describe two new Eocene fossil berries of the nightshade family (Solanaceae) from the Esmeraldas Formation in Colombia and the Green River Formation in Colorado (USA). The placement of the fossils was assessed using clustering and parsimony analyses based on 10 discrete and five continuous characters, which were also scored in 291 extant taxa. The Colombian fossil grouped with members of the tomatillo subtribe, and the Coloradan fossil aligned with the chili pepper tribe. Along with two previously reported early Eocene fossils from the tomatillo genus, these findings indicate that Solanaceae were distributed at least from southern South America to northwestern North America by the early Eocene. Together with two other recently discovered Eocene berries, these fossils demonstrate that the diverse berry clade and, in turn, the entire nightshade family, is much older and was much more widespread in the past than previously thought.


Assuntos
Capsicum , Solanum , Fósseis , Frutas , América do Sul , Filogenia
13.
J. venom. anim. toxins incl. trop. dis ; 29: e20230040, 2023. ilus, mapas
Artigo em Inglês | VETINDEX | ID: biblio-1452405

RESUMO

This synoptic review aims to bring some general information on fossil scorpions, namely those trapped in amber - fossilized resin - ranging from Lower Cretaceous through the Palaeocene and up to the Miocene. The question to be addressed is how the study of these fossils can be connected with possible present scorpionism problems. A precise knowledge of these ancient lineages provides information about the evolution of extant lineages, including the buthoids, which contain most known noxious species. Among the Arthropods found trapped in amber, scorpions are considered rare. A limited number of elements have been described from the Late Tertiary Dominican and Mexican amber, while the most ancient Tertiary amber from the Baltic region produced more consistent results in the last 30 years, primarily focusing on a single limited lineage. Contrarily, the Cretaceous amber from Myanmar, also called Burmite, has yielded and continues to yield a significant number of results represented by several distinct lineages, which attest to the considerable degree of diversity that existed in the Burmese amber-producing forests. As in my previous similar contributions to this journal, the content of this note is primarily addressed to non-specialists whose research embraces scorpions in various fields such as venom toxins and public health. An overview knowledge of at least some fossil lineages can eventually help to clarify why some extant elements associated with the buthoids represent dangerous species while others are not noxious.(AU)


Assuntos
Animais , Escorpiões/anatomia & histologia , Âmbar/análise , Fósseis
14.
Pap. avulsos zool ; 63: e202363019, 2023. tab, ilus, mapas
Artigo em Inglês | VETINDEX | ID: biblio-1448756

RESUMO

The Continental African abelisauroid theropod dinosaur fossil record from the Jurassic-Cretaceous periods is becoming increasingly better understood, and offers great insight into the evolution and biogeography of this long-lived group of carnivores. Abelisauroidea is among the most familiar groups of theropod dinosaurs from Gondwana, with fossil records in South America, Australia, India and Africa, along with Europe. The objective of the present study is to review the fossil record of abelisauroids in continental Africa. Based on the literature and records from the online databases "The Paleobiology Database" and "The Theropod Database", we review the distribution of these theropods in Africa and comment on their evolution. The African continent is a major region of importance when it comes to 26 Abelisauroidea fossil findings, including records of both major subdivisions of the clade: the Abelisauridae and Noasauridae families. The oldest Abelisauroidea fossil record found in Africa dates from the Late Jurassic, while the final records date from the end of the Cretaceous. This indicates that clade was the longest surviving lineage of the large theropods of Africa, and they filled a variety of ecological roles, including apex predators, at the end of the Cretaceous, when tyrannosaurids occupied similar niches in the northern continents.


Assuntos
Animais , Dinossauros/classificação , Fósseis , África
15.
Pap. avulsos zool ; 63: e202363012, 2023. graf
Artigo em Inglês | VETINDEX | ID: biblio-1431025

RESUMO

In describing Cyclocancer to accommodate his new species C. tuberculatus, Beurlen highlighted that his new genus was a cancroid intermediate in form between Atelecyclus and Cancer, but with enough characters to be placed in a new genus. Examination of C. tuberculatus type material revealed that Cyclocancer is a junior synonym of Hepatus. Therefore, C. tuberculatus is herein transferred into Hepatus as H. beurleni nomen novum because H. tuberculatus (Beurlen, 1958) is a junior homonym of H. tuberculatusSaussure (1858), a junior synonym of Hepatus pudibundus (Herbst, 1785). Miohepatus gen. nov., comb. nov. is proposed here to accommodate Hepatella amazonica Beurlen from the Pirabas Formation, Neogene, Pará, Brazil, based on new morphological evidence from the type material.(AU)


Assuntos
Animais , Decápodes/anatomia & histologia , Decápodes/classificação , Especificidade da Espécie , Brasil
16.
Pap. avulsos zool ; 63: e202363014, 2023.
Artigo em Inglês | VETINDEX | ID: biblio-1434549

RESUMO

Santana et al. (2022) described a new genus and species of fossil crab, Chronocancer camilosantanai, from carbonate concretions of the Romualdo Formation of the Araripe Sedimentary Basin. The journal in which the description appeared was published online only and the new name did not include a ZooBank registration number (LSID), as required for validation of new names in electronic-only publications. The present note serves to validate the name Chronocancer camilosantanai by fulfilling the ICZN conditions for nomenclatural availability. The date and authorship of the specific name, accordingly, are those of this note, not Santana et al. (2022).(AU)


Assuntos
Animais , Braquiúros/anatomia & histologia , Braquiúros/classificação , Brasil , Fósseis
17.
J. venom. anim. toxins incl. trop. dis ; J. venom. anim. toxins incl. trop. dis;29: e20230040, 2023. graf, ilus, mapas
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1506644

RESUMO

This synoptic review aims to bring some general information on fossil scorpions, namely those trapped in amber - fossilized resin - ranging from Lower Cretaceous through the Palaeocene and up to the Miocene. The question to be addressed is how the study of these fossils can be connected with possible present scorpionism problems. A precise knowledge of these ancient lineages provides information about the evolution of extant lineages, including the buthoids, which contain most known noxious species. Among the Arthropods found trapped in amber, scorpions are considered rare. A limited number of elements have been described from the Late Tertiary Dominican and Mexican amber, while the most ancient Tertiary amber from the Baltic region produced more consistent results in the last 30 years, primarily focusing on a single limited lineage. Contrarily, the Cretaceous amber from Myanmar, also called Burmite, has yielded and continues to yield a significant number of results represented by several distinct lineages, which attest to the considerable degree of diversity that existed in the Burmese amber-producing forests. As in my previous similar contributions to this journal, the content of this note is primarily addressed to non-specialists whose research embraces scorpions in various fields such as venom toxins and public health. An overview knowledge of at least some fossil lineages can eventually help to clarify why some extant elements associated with the buthoids represent dangerous species while others are not noxious.(AU)


Assuntos
Animais , Escorpiões/anatomia & histologia , Fósseis , Âmbar/análise
18.
Biology (Basel) ; 11(8)2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-36009785

RESUMO

Evidence that organic material preserves in deep time (>1 Ma) has been reported using a wide variety of analytical techniques. However, the comprehensive geochemical data that could aid in building robust hypotheses for how soft-tissues persist over millions of years are lacking from most paleomolecular reports. Here, we analyze the molecular preservation and taphonomic history of the Dreadnougtus schrani holotype (MPM-PV 1156) at both macroscopic and microscopic levels. We review the stratigraphy, depositional setting, and physical taphonomy of the D. schrani skeletal assemblage, and extensively characterize the preservation and taphonomic history of the humerus at a micro-scale via: (1) histological analysis (structural integrity) and X-ray diffraction (exogenous mineral content); (2) laser ablation-inductively coupled plasma mass spectrometry (analyses of rare earth element content throughout cortex); (3) demineralization and optical microscopy (soft-tissue microstructures); (4) in situ and in-solution immunological assays (presence of endogenous protein). Our data show the D. schrani holotype preserves soft-tissue microstructures and remnants of endogenous bone protein. Further, it was exposed to LREE-enriched groundwaters and weakly-oxidizing conditions after burial, but experienced negligible further chemical alteration after early-diagenetic fossilization. These findings support previous hypotheses that fossils that display low trace element uptake are favorable targets for paleomolecular analyses.

19.
Am J Bot ; 109(6): 986-1003, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35567490

RESUMO

PREMISE: Two distinct types of fossil infructescences from the early Eocene Laguna del Hunco flora, Chubut Province, Patagonia, Argentina, preserve features of the family Cunoniaceae. The goal of the study was to assess their affinities within Cunoniaceae and to interpret their evolutionary and biogeographical significance. METHODS: Specimens were collected from the Tufolitas Laguna del Hunco, Huitrera Formation. They were prepared, photographed, and compared morphologically with similar extant and fossil fruits and infructescences using published literature and herbarium material. RESULTS: The fruit and infructescence morphology place the fossil taxa within Cunoniaceae. They do not conform to any extant genus, supporting the erection of two new fossil genera. Racemofructus gen. nov. shares diagnostic features of the tribe Cunonieae, especially Weinmannia s.l., and exhibits two tribal morphological synapomorphies: a racemose inflorescence and a replum composed of a single column. Cunoniocarpa gen. nov. specimens are paniculate inflorescences with basipetally dehiscent, bicarpellate capsules that have persistent styles and calyces. Its replum morphology suggests an affinity to the tribe Caldcluvieae, particularly to the genus Ackama. CONCLUSIONS: The new Patagonian fossils described herein constitute the oldest record of cunoniaceous capsules globally, supplementing a significant body of fossil evidence from pollen, wood, and reproductive structures from southern South America and Antarctica that suggests that the Cunoniaceae were diversified and widely distributed in the southern hemisphere by the early Eocene. Racemofructus and Cunoniocarpa are, respectively, the first fossil records from South America of reproductive structures with affinity to tribes Cunonieae and Caldcluvieae.


Assuntos
Evolução Biológica , Fósseis , Argentina , Cápsulas , Flores/anatomia & histologia
20.
Cladistics ; 38(5): 538-562, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35475520

RESUMO

Filistatids, the crevice weavers, are an ancient family of cribellate spiders without extant close relatives. As one of the first lineages of araneomorph spiders, they present a complicated mixture of primitive and derived characters that make them a key taxon to elucidate the phylogeny of spiders, as well as the evolution of phenotypic characters in this group. Their moderate diversity (187 species in 19 genera) is distributed mainly in arid and semi-arid subtropical zones of all continents, except Antarctica. The objective of this paper is to generate a comprehensive phylogenetic hypothesis for this family to advance the understanding of its morphological evolution and biogeography, as well as lay the basis for a natural classification scheme. By studying the morphology using optical and electronic microscopy techniques, we produced a matrix of 302 morphological characters coded for a sample of 103 species of filistatids chosen to represent the phylogenetic diversity of the family. In addition, we included sequences of four molecular markers (COI, 16S, H3 and 28S; 3787 aligned positions) of 70 filistatid species. The analysis of the data (morphological, molecular, and combined) consistently indicates the separation of the Filistatidae into two subfamilies, Prithinae and Filistatinae, in addition to supporting several groups of genera: Filistata, Zaitunia and an undescribed genus from Madagascar; Sahastata and Kukulcania; all Prithinae except Filistatinella and Microfilistata; Antilloides and Filistatoides; a large Old World group including Pritha, Tricalamus, Afrofilistata, Labahitha, Yardiella, Wandella and putative new genera; and a South American group formed by Lihuelistata, Pikelinia and Misionella. Pholcoides is transferred to Filistatinae and Microfilistata is transferred to Prithinae, and each represents the sister group to the remaining genera of its own subfamily. Most genera are valid, although Pikelinia is paraphyletic with respect to Misionella, so we consider the two genera as synonyms and propose a few new generic combinations. Considering the new phylogenetic hypothesis, we discuss the evolution of some morphological character systems and the biogeography of the family. The ages of divergence between clades were estimated using a total-evidence tip-dating approach by including fossils of Filistatidae and early spider clades; this approach resulted in younger age estimates than those obtained with traditional node-dating. Filistatidae is an ancient family that started diversifying in the Mesozoic and most genera date to the Cretaceous. Clades displaying transcontinental distributions were most likely affected by continental drift, but at least one clade shows unequivocal signs of transoceanic long-distance dispersal.


Assuntos
Aranhas , Animais , Regiões Antárticas , Fósseis , Madagáscar , Filogenia , Aranhas/genética
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