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1.
Acta Trop ; 211: 105614, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32621936

RESUMO

In this study, the first records of lesions in osteoderms of Holmesina, a group of fossil cingulates related to armadillos, possibly caused by the action of penetrating fleas (Siphonaptera) are described. Three individuals of Holmesina cryptae (Pampatheriidae) were collected from Quaternary sediments in Lapinha Cave (Iramaia, Bahia state, Brazil). Their osteoderms were analyzed by stereomicroscope and scanning electron microscopy and alterations on their surfaces were recognized. We found 63 marks distributed in 23 of 1300 analyzed osteoderms (approximately 1.8% of the total of osteoderms), characterized by vertical cavities with well-delimited circular borders similar to those lesions made by Tungidae fleas in extant mammals. These records indicate that there was an interaction between penetrating fleas and pampatheres during the Quaternary in Brazilian Intertropical Region, and contribute to the understanding of the evolution of these ectoparasites and the relationship with their hosts.


Assuntos
Fósseis/parasitologia , Sifonápteros/crescimento & desenvolvimento , Xenarthra/parasitologia , Animais , Brasil , Paleopatologia
2.
PeerJ ; 8: e8880, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32509444

RESUMO

The new ichnospecies Paleohelcura araraquarensis isp. nov. is described from the Upper Jurassic-Lower Cretaceous Botucatu Formation of Brazil. This formation records a gigantic eolian sand sea (erg), formed under an arid climate in the south-central part of Gondwana. This trackway is composed of two track rows, whose internal width is less than one-quarter of the external width, with alternating to staggered series, consisting of three elliptical tracks that can vary from slightly elongated to tapered or circular. The trackways were found in yellowish/reddish sandstone in a quarry in the Araraquara municipality, São Paulo State. Comparisons with neoichnological studies and morphological inferences indicate that the producer of Paleohelcura araraquarensis isp. nov. was most likely a pterygote insect, and so could have fulfilled one of the ecological roles that different species of this group are capable of performing in dune deserts. The producer could have had a herbivorous or carnivorous diet or been part of the fauna of omnivores, being able to adopt herbivorous, carnivorous, and saprophagous diets when necessary. In modern dune deserts, some species of pterygote insects are detritivores (like Tenebrionidae), relying on organic matter that accumulated among the sand grains of the dunes during dry periods with no plant growth. The presence of additional burrows suggests that the Botucatu paleodesert would have had a detritivorous fauna like this. Based on the interpretation of the ichnofossil producers, it was possible to reconstruct the food web of this paleodesert. All the omnivorous and herbivorous invertebrates and the herbivorous ornithopod dinosaurs made up the primary consumers. These animals were, in turn, the food source for bigger carnivorous or omnivorous animals unable to feed on detritus, like arachnids, possible predatory insects, mammaliaforms, and theropod dinosaurs. The highest trophic level was occupied by larger theropod dinosaurs and mammaliaforms, which, because of their size, could prey upon a wide range of animals. The producer of Paleohelcura araraquarensis isp. nov. could have been a primary consumer if it were an omnivorous detritivore or a herbivore, or a secondary consumer if it were produced by a predatory insect or an omnivore relying on animal biomass. The description of this new trackway expands the knowledge on the faunal composition of the Botucatu paleodesert and provides insights into the ecological relationships in ancient deserts. The presence of these arthropod trackways in Mesozoic eolian deposits helps to trace a continuity between Paleozoic and post-Paleozoic desert ichnofaunas, further reinforcing a single Octopodichnus-Entradichnus Ichnofacies for eolian deposits.

3.
Zootaxa ; 4661(3): zootaxa.4661.3.1, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31716695

RESUMO

Pampatheriidae is a group of South American native cingulates recorded from the Middle Miocene to the Early Holocene. These animals arrived in North America during the Great American Biotic Interchange. During the Quaternary, at least three genera existed: Tonnicinctus Góis, González Ruiz, Scillato-Yané and Soibelzon, Pampatherium Gervais and Ameghino, and Holmesina Simpson. They are differentiated mainly by craniodental and osteodermal characters. In this paper, we describe a new species of Holmesina from Bahia state, Brazil. Two well-preserved specimens possessing osteoderms associated with their skeletons enabled us to determine the genus and species more reliably. Holmesina cryptae sp. nov. differs from the other Quaternary pampatheres by having the simplest ornamental pattern of osteoderms, sharing characteristics between Pampatherium and Holmesina osteoderms and the most robust skull among the Holmesina species, however preserving the main synapomorphies of the genus. Moreover, the integrity of the remains of H. cryptae sp. nov. enabled us to describe elements of the hyoid apparatus, the clavicle, the entire vertebral column and the pelvis. It was also possible to measure its total axial length (2.2 m) more reliably, which is smaller than previously estimated for other pampatheres. Holmesina cryptae sp. nov. constitutes the sixth species of the genus, and it is the fourth in South America.


Assuntos
Xenarthra , Animais , Brasil , América do Norte , Crânio
4.
Radiat Prot Dosimetry ; 172(1-3): 296-301, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27473703

RESUMO

Electron spin resonance (ESR) dating was applied to date a sample of fossil tooth found in Ribeira Valley, São Paulo, Brazil. This region is characterized by abundant fossil records of Pleistocene-Holocene South American megafauna belonging to different faunistic moments related to climate changes during the quaternary. As the number of fossils dated is not too large, the dating of materials from this region will provide important information to better understand the events associated with the presence and extinction of these species. The equivalent dose (De) was determined using single exponential fitting resulting in (24 ± 1)Gy. The De was converted to age using ROSY ESR Dating program and the concentration of radioisotopes present in the sample and soil determined through neutron activation analysis. The ages cover the range of 25-34 ka. This information is important to contextualize other findings in the region from different sites and to help obtain better information about the climate changes in this region.


Assuntos
Bioensaio/métodos , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Fósseis , Datação Radiométrica/métodos , Dente/química , Dente/efeitos da radiação , Animais , Brasil , Mamíferos , Doses de Radiação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Rev. bras. entomol ; Rev. bras. entomol;54(2): 263-269, Apr.-June 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-553862

RESUMO

Parasitoids of the family Ichneumonidae (Hymenoptera) were obtained during an inventory of Lepidoptera larvae caught feeding in the wild on Croton floribundus (Euphorbiaceae). The Lepidoptera larvae were collected from host plants along trails inside three preserved forest areas in the Brazilian state of São Paulo. Fifteen different species of Ichneumonidae belonging to five subfamilies (Banchinae, Campopleginae, Cremastinae, Mesochorinae and Metopiinae) were obtained. Seven species of Ichneumonidae were reared from leaf rollers: Meniscomorpha sp. (Banchinae) and Leurus caeruliventris (Cresson) (Metopiinae) from Dichomeris sp. (Gelechiidae); Mesochorus sp.1 (Mesochorinae) [as a parasitoid of Hypomicrogaster sp. (Braconidae, Microgastrinae)], Campoplex sp. (Campopleginae) and Leurus sp. from Olethreutinae sp. (Tortricidae); Sphelodon annulicornis Morley (Banchinae) and Eutanygaster brevipennis Cameron (Cremastinae) were also reared from two unidentified species of Gelechiidae. The other eight species were reared from the larvae of exposed feeders: Diradops sp. (Banchinae) from Miselia albipuncta Hampson (Noctuidae), Casinaria sp. (Campopleginae) from Hymenomima conia Prout (Geometridae), Charops sp. (Campopleginae) from Bagisara paulensis Schaus (Noctuidae) and Oxydia vesulia (Cramer) (Geometridae), two species of Hyposoter Fõrster (Campopleginae) from Semaeopus sp. (Geometridae) and H. conia, two species of Microcharops Roman (Campopleginae) from B. paulensis and an unidentified species of Limacodidae and Mesochorus sp. 2 [reared from what was probably Aleiodes sp. (Braconidae, Rogadinae)] from an unidentified species of Noctuidae.


Parasitóides da família Ichneumonidae (Hymenoptera) foram obtidos durante um inventário de larvas de Lepidoptera sobre Croton floribundus (Euphorbiaceae). As larvas de Lepidoptera foram coletadas sobre as plantas que ocorrem nas bordas de caminhos em três áreas preservadas de mata do Estado de São Paulo, Brasil. Quinze espécies pertencentes a cinco subfamílias (Banchinae, Campopleginae, Cremastinae, Mesochorinae and Metopiinae) foram registradas. Sete espécies de Ichneumonidae foram obtidas de larvas que elaboram abrigos: Meniscomorpha sp. (Banchinae) e Leurus caeruliventris (Cresson) (Metopiinae) parasitóides de Dichomeris sp. (Gelechiidae); Mesochorus sp.1 (Mesochorinae) [parasitóide de Hypomicrogaster sp. (Braconidae, Microgastrinae)], Campoplex sp. (Campopleginae) e Leurus sp. sobre Olethreutinae sp. (Tortricidae); Sphelodon annulicornis Morley (Banchinae) e Eutanygaster brevipennis Cameron (Cremastinae) parasitóides de duas espécies não identificadas de Gelechiidae. As outras oito espécies foram obtidas de larvas encontradas em situações expostas: Diradops sp. (Banchinae) sobre Miselia albipuncta Hampson (Noctuidae), Casinaria sp. (Campopleginae) sobre Hymenomima conia Prout (Geometridae), Charops sp. (Campopleginae) parasitóide de Bagisara paulensis Schaus (Noctuidae) e Oxydia vesulia (Cramer) (Geometridae), duas espécies de Hyposoter Fõrster (Campopleginae) sobre Semaeopus sp. (Geometridae) e H. conia, duas espécies de Microcharops Roman (Campopleginae) sobre Bagisara paulensis e Limacodidae sp., e Mesochorus sp. 2 [provavelmente parasitóide de Aleiodes sp. (Braconidae, Rogadinae)] sobre espécie não identificada de Noctuidae.

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