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2.
Proc Biol Sci ; 288(1960): 20211760, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34610770

RESUMO

Tardigrades are a diverse group of charismatic microscopic invertebrates that are best known for their ability to survive extreme conditions. Despite their long evolutionary history and global distribution in both aquatic and terrestrial environments, the tardigrade fossil record is exceedingly sparse. Molecular clocks estimate that tardigrades diverged from other panarthropod lineages before the Cambrian, but only two definitive crown-group representatives have been described to date, both from Cretaceous fossil deposits in North America. Here, we report a third fossil tardigrade from Miocene age Dominican amber. Paradoryphoribius chronocaribbeus gen. et sp. nov. is the first unambiguous fossil representative of the diverse superfamily Isohypsibioidea, as well as the first tardigrade fossil described from the Cenozoic. We propose that the patchy tardigrade fossil record can be explained by the preferential preservation of these microinvertebrates as amber inclusions, coupled with the scarcity of fossiliferous amber deposits before the Cretaceous.


Assuntos
Âmbar , Fósseis , Evolução Biológica , América do Norte
3.
Sci Rep ; 9(1): 20220, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882600

RESUMO

With approximately 1,500 extant species, freshwater crabs (Decapoda: Brachyura) are among the most diverse decapod crustaceans. Nevertheless, their fossil record is extremely limited: only Potamidae, Potamonautidae and Trichodactylidae are reported up to the Eocene of the Neotropics so far. This work documents unusually large decapod claws from the Upper Cretaceous (Campanian) continental deposits of Velaux and vicinity (southern France), in close association with large vertebrate remains. In addition to (1) the systematic assignment of these claws, the study addresses (2) the salinity trends in the deposit environment from its faunal assemblage and the elementary chemical patterns of fossils, and (3) the likely scenario for their auto/allochthony in the Velaux fluvial system. These claws belong to a new taxon, Dinocarcinus velauciensis n. gen. n. sp., referred to as Portunoidea sensu lato, a group of "true" crabs nowadays linked to marine systems. However, the faunal assemblage, the claw taphonomy and the carbonates Y/Ho signatures support their ancient freshwater/terrestrial ecology, making them the oldest reported continental brachyurans and extending the presence of crabs in freshwater environments by 40 Ma. Either as primary or as secondary freshwater crabs, the occurrence of these portunoids in Velaux is an evidence for the independent colonizations of continental environments by multiple brachyuran clades over time, as early as the Campanian.


Assuntos
Osso e Ossos/anatomia & histologia , Braquiúros/anatomia & histologia , Dinossauros/anatomia & histologia , Fósseis , Casco e Garras/anatomia & histologia , Animais , Evolução Biológica , Braquiúros/classificação , Dinossauros/classificação , Água Doce , Modelos Biológicos , Paleontologia/métodos , Especificidade da Espécie
4.
BMC Evol Biol ; 19(1): 213, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752661

RESUMO

BACKGROUND: Dispersal is essential for terrestrial organisms living in disjunct habitats and constitutes a significant challenge for the evolution of wingless taxa. Springtails (Collembola), the sister-group of all insects (with Diplura), are reported since the Lower Devonian and are thought to have originally been subterranean. The order Symphypleona is reported since the early Cretaceous with genera distributed on every continent. This distribution implies an ability to disperse over oceans, however symphypleonan Collembola have never been reported in marine water contrary to other springtail orders. Despite being highly widespread, modern springtails are rarely reported in any kind of biotic association. Interestingly, the fossil record has provided occasional occurrences of Symphypleona attached by the antennae onto the bodies of larger arthropods. RESULTS: Here, we document the case of a ~ 16 Ma old fossil association: a winged termite and ant displaying not some, but 25 springtails attached or in close proximity to the body. The collembola exhibit rare features for fossils, reflecting their courtship and phoretic behaviours. By observing the modes of attachment of springtails on different arthropods, the sex representation and ratios in springtail antennal anatomies in new and previously reported cases, we infer a likely mechanism for dispersal in Symphypleona. By revealing hidden evidence of modern springtail associations with other invertebrates such as ants and termites, new compelling assemblages of fossil springtails, and the drastic increase of eusocial insects' abundance during the Cenozoic (ants/termites comprising more than a third of insects in Miocene amber), we stress that attachment on winged castes of ants and termites may have been a mechanism for the worldwide dispersal of this significant springtail lineage. Moreover, by comparing the general constraints applying to the other wingless soil-dwelling arthropods known to disperse through phoresy, we suggest biases in the collection and observation of phoretic Symphypleona related to their reflexive detachment and infer that this behaviour continues today. CONCLUSIONS: The specific case of tree resin entrapment represents the (so far) only condition uncovering the phoretic dispersal mechanism of springtails - one of the oldest terrestrial arthropod lineages living today.


Assuntos
Artrópodes/anatomia & histologia , Artrópodes/fisiologia , Fósseis , Âmbar , Animais , Formigas , Artrópodes/classificação , Evolução Biológica , Ecossistema , Isópteros , Masculino , Solo
5.
Sci Rep ; 9(1): 5332, 2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30926859

RESUMO

Exceptional and extremely rare preservation of soft parts, eyes, or syn-vivo associations provide crucial palaeoecological information on fossil-rich deposits. Here we present exceptionally preserved specimens of the polychelidan lobster Voulteryon parvulus, from the Jurassic of La Voulte-sur-Rhône Fossil-Lagerstätte, France, bearing eyes with hexagonal and square facets, ovaries, and a unique association with epibiont thecideoid brachiopods, giving insights onto the palaeoenvironment of this Lagerstätte. The eyes, mostly covered in hexagonal facets are interpreted as either apposition eyes (poorly adapted to low-light environment) or, less likely, as refractive or parabolic superposition eyes (compatible with dysphotic palaeoenvironments). The interpretation that V. parvulus had apposition eyes suggests an allochthonous, shallow water origin. However, the presence of thecideoid brachiopod ectosymbionts on its carapace, usually associated to dim-light paleoenvironments and/or rock crevices, suggests that V. parvulus lived in a dim-light setting. This would support the less parsimonious interpretation that V. parvulus had superposition eyes. If we accept the hypothesis that V. parvulus had apposition eyes, since the La Voulte palaeoenvironment is considered deep water and had a soft substrate, V. parvulus could have moved into the La Voulte Lagerstätte setting. If this is the case, La Voulte biota would record a combination of multiple palaeoenvironments.


Assuntos
Decápodes , Fósseis , Paleontologia , Animais , Decápodes/anatomia & histologia , França
6.
Sante Publique ; Vol. 31(4): 561-566, 2019.
Artigo em Francês | MEDLINE | ID: mdl-31959257

RESUMO

INTRODUCTION: Spontaneous reporting remains one of the cornerstones of post-marketing drug safety surveillance. One of its main limitations is a lack of completeness.The main aim of this study was to assess the completeness of pharmacovigilance reports sent by general practitioners (GPs) to regional pharmacovigilance centers (RPC) reported in the French pharmacovigilance database (FPVD). Secondary aim was to identify factors associated with complete reports. METHOD: All adverse drugs reactions (ADRs) sent by GPs in France in 2015 were analyzed. According to information provided in ADR reports (ADR, date of occurrence, clinical description, drugs suspected, etc.), completeness was analyzed from “mandatory” criteria (age, gender, ADR and suspected drug(s)) and “non-mandatory” criteria (medical history, concomitant drugs, symptoms evolution and complementary exams) and classified as “well-documented”, “slightly-documented” or “poorly-documented”. RESULTS: In 2015, the FPVD contained 3,020 ADR reports realized by GPs. Only 16.4% of these reports were classified as “well-documented”, in accordance with study criteria. The most poorly documented items were concomitant drugs (41.4%) and complementary exams (37.4%). An association between a “well-documented” ADR report and its “seriousness” (OR = 3,02 [95% CI 2,44; 3,23], P < 10–3) and elderly compared to adults (OR = 1,76 [95% CI 1,42; 2,18], P < 10–3) or children (OR = 4,59 [95% CI 2,51; 8,39], P < 10–3). CONCLUSION: Our study shows that only one out of six ADR reports was “well-documented”. It appears to be important to promote pharmacovigilance to improve completeness of ADR reports.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos/normas , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Clínicos Gerais , Farmacovigilância , Padrões de Prática Médica/normas , França , Humanos
7.
Naturwissenschaften ; 103(9-10): 85, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27689232

RESUMO

Coprolites of terrestrial vertebrates from the Sparnacian Le Quesnoy locality (Ypresian, Eocene, MP7, 53 Ma; Oise, France) were examined for possible parasitic helminth eggs. The extraction of the coprolite components was performed by a weak acetolyse and a slide mounting in glycerin. This long examination did not reveal paleoparasite remains, which may be explained through several arguments. However, some pollen grains, some enigmatic components, and two well-preserved first-instar cochineal nymphs (Hemiptera: Sternorrhyncha: Coccoidea) were evidenced in coprolites. Identified as Coccidae, these larvae are the earliest stage of the scale insect development ever reported as fossil, revealing the specific environment of preservation that fossilized scats may provide. These observations, combined to the coprolites morphotype, enable to ascribe the fossil scats producer to a small herbivorous mammal present in the deposit (early perissodactyls or Plesiadapidae). Regarding the ecology of extant representatives of Coccidae, this mammal was a likely foliage consumer, and the abundant Juglandaceae and/or Tiliaceae from Le Quesnoy might have lived parasitized by scale insects. These Early Eocene parasites had an already well-established dissemination strategy, with prevalent minute first-instar larvae. The herein performed extraction technique appears well-suited for the study of carbonate coprolites and could certainly be useful for evidencing other kind of microorganisms (including internal parasites).


Assuntos
Fezes , Fósseis , Hemípteros/fisiologia , Vertebrados , Animais , Fezes/parasitologia , França , Herbivoria , Larva
8.
Curr Biol ; 26(10): 1376-82, 2016 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-27161503

RESUMO

Symbiosis [1], understood as prolonged interspecific association, is as ancient as the eukaryotic cell [2, 3]. A variety of such associations have been reported in the continental fossil record, albeit sporadically. As for mites, which as a group have been present since the Devonian (ca. 390 mya) [4, 5] and are involved in a tremendous variety of modern-day symbioses, reported associations are limited to a few amber-preserved cases [6-11], with the earliest instance in the Cretaceous (ca. 85 mya) [11]. As a consequence, the antiquity and origin of associations involving small-sized mites and larger animals are poorly understood. Here we report, recovered from the Carboniferous Xiaheyan locality (ca. 320 mya), an oribatid mite located on the thorax of an extinct relative of grasshoppers, crickets, and katydids [12]. The mite was investigated using several methods, including phase-contrast tomography. The detailed morphological data allowed the placement of the mite in a new family within Mixonomata, whose fossil record is thus extended by ca. 250 Ma. Specimen and abundance distribution data derived from the fossil insect sample indicate that specimens from the corresponding excavation site were buried rapidly and were sub-autochthonous, indicating a syn vivo association. Moreover, the mite is located in a sequestered position on the insect. The observed interaction best fits the definition for phoresy, in which the benefit is transport and protection for the mite. This discovery demonstrates that this association, a trait shared by representatives of the most speciose mite taxa, arose very early during mite evolution.


Assuntos
Evolução Biológica , Insetos/fisiologia , Ácaros/classificação , Ácaros/fisiologia , Simbiose , Animais , China , Fósseis/anatomia & histologia , Insetos/anatomia & histologia , Ácaros/anatomia & histologia , Filogenia
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