Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
PeerJ ; 12: e16670, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38188171

RESUMO

Background: A new fossil species of whipscorpion, Mesoproctus rayoli n. sp., is described. The specimen originates from the Crato Formation, dating to the Lower Cretaceous (Aptian/Albian) period within the Araripe Sedimentary Basin. This species has been provisionally assigned to Mesoproctus Dunlop, 1998, as it represents the sole known Thelyphonida fossil genus discovered in South America and within Araripe Lagerstätte. Methods: The material underwent detailed description and illustration processes. Key diagnostic characters, such as body length, pedipalpal coxae apophysis, the form of the opisthosoma, and the length of leg IV, were meticulously examined. SEM methods were applied in this study. Results: Through the detailed analysis, comparisons and differences to Mesoproctus rowlandi Dunlop, 1998 were made possible. Additionally, a well-preserved specimen of the rare camel spider, Cratosolpuga wunderlichi Selden, in Selden and Shear, 1996, was identified from the limestones of the Crato Formation. The newly discovered fossil specimen of Cratosolpuga wunderlichi suggests two characters not previously described: (i) a segmented tarsomere on leg IV; and (ii) a leg I with one tarsal claw.


Assuntos
Aracnídeos , Aranhas , Animais , Brasil , Fósseis , Carbonato de Cálcio , Camelus
2.
Sci Rep ; 13(1): 14549, 2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37666850

RESUMO

Direct evidence of paleo-parasitism in crustaceans is very scarce. Epicaridean isopods are obligatory parasites of crustaceans, including decapods such as crabs, shrimps, and lobsters. Their interaction with hosts is known from fossils as far back as the Jurassic through deformations of the branchial cuticle on the hosts. Their small size and low fossilization potential, outside of those larvae that have been found in amber, makes understanding the group's evolution challenging. Here, we report the oldest evidence of paleo-parasitism in marine shrimps and an imprint of a putative adult parasite that appears to be an epicaridean isopod. Our results suggest that the parasite-host interaction between epicaridean isopods and marine shrimps started at least 110 million years ago, and the Tethys Sea was a possible dispersal pathway for this lineage of parasites during the Jurassic and Cretaceous, as known for other marine organisms through most of the Mesozoic and Cenozoic. The oldest fossil records of bopyrid swellings associated with a large number of decapods from the Jurassic in Europe suggest that the Tethys region was a center of epicaridean distribution as a whole. Recent parasitic isopods found on dendrobranchiate shrimps are restricted to the Indo-Pacific and may represent a relict group of a lineage of parasites more widely distributed in the Mesozoic.


Assuntos
Decápodes , Gastrópodes , Isópodes , Animais , Fósseis , Âmbar , Europa (Continente)
4.
Zootaxa ; 5314(1): 1-62, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37518623

RESUMO

Here we provide an illustrated and annotated checklist of brachyuran crabs associated with shallow water marine habitats (nearshore rubble and subtidal) in Barbados, West Indies (13.1939°N, 59.5432°W). Twenty-one (21) survey sites in nearshore rubble and shallow subtidal habitats were surveyed between October 2018 to September 2021. Nearshore rubble habitats were surveyed at low tide during the day and night periods. Shallow nearshore subtidal habitats were surveyed every 9-12 days from February to October 2019 using crab traps placed ~ 4 m deep on sandy and rocky bottoms. A total of 1,640 specimens were recorded, belonging to nine (9) superfamilies, 14 families, 34 genera, and 44 species. The genera Charybdis De Haan, 1833, Pitho Bell, 1835, Thoe Bell, 1835, and Uhlias Stimpson, 1871 are here reported for the first time for Barbados. Thirteen (13) species are first records for Barbados, thus extending their geographic range. The most abundant and widespread species collected was Mithraculus coryphe Herbst, 1801, which accounted for 35% (N = 570) of the specimens, occurring in both nearshore rubble and subtidal habitats.


Assuntos
Braquiúros , Infestações por Piolhos , Humanos , Animais , Barbados , Água , Índias Ocidentais
5.
PLoS One ; 18(3): e0281334, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36947562

RESUMO

Stenopodidean shrimps are mostly cryptic in their habitats and are typically related with coral rubble or dead coral heads, rocks and crevices, and in association with other marine invertebrate such as sponges, crinoids and corals. Here, we describe a new stenopodidean shrimp, Dubiostenopus parvus n. gen. n. sp., from the Romualdo Formation (Aptian/Albian), Araripe Sedimentary Basin. The specimen studied here was collected in the municipality of Trindade, Pernambuco State, Brazil. The specimen is the imprint of a small shrimp approximately 10 mm in length, with a robust cephalothorax, a well-developed cheliped in the third pereiopod, and a second pleura not overlapping the first. This is the first stenopodidean shrimp described from the Romualdo Formation and the first described from South America. Comparisons with other Brazilian shrimp-like fossils are made, as well as comparisons with all other fossil stenopodideans.


Assuntos
Antozoários , Decápodes , Animais , Brasil , Crustáceos , Fósseis , Ecossistema
6.
Arthropod Struct Dev ; 66: 101132, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34863064

RESUMO

Several majoid crabs are known to adhere exogenous materials to their bodies, a behaviour called decoration. Until now, the adhesion of exogenous materials to the body is most attributed to the well-known hooked setae. Here, we analysed the carapace of Macrocoeloma trispinosum (Latreille, 1825) under light and electron microscopy to study the different mechanisms allowing majoid crabs to decorate themselves. Five setal types are described here, of which four for the first time: velvet type I, velvet type II, depressa and cattail seta. These setae are morphologically and histologically detailed, and new hypotheses about the fixation of exogenous material on the carapace are explored. M. trispinosum has a complex setal apparatus for the adhesion of the decoration, with tegumental ducts along the shaft of most setae. These tegumental ducts are connected to glands formed by large cells arranged radially (rosette or acini) at the base of the setae, in the connective tissue, just below the epithelium. We could observe these glands in different stages of maturation, and no valve-like structure was observed, which may indicate a continuous flow of protein secretion that could serve as an adhesive substance found in the apex of most setae. This is the first record indicating a potential chemical adhesion mechanism aiding the masking process in decorator crabs.


Assuntos
Braquiúros , Exoesqueleto , Animais , Braquiúros/anatomia & histologia , Sensilas
7.
Motriz (Online) ; 28: e10220016521, 2022. tab
Artigo em Inglês | LILACS | ID: biblio-1375936

RESUMO

Abstract Aim: Social distancing policies to combat the pandemic of COVID-19 directly impacted the physical activity (PA) index of the population. This study aimed to analyze the factors associated with insufficient leisure-time PA and the changing behavior of residents of the city of Sao Paulo, the epicenter of the pandemic in Brazil. Methods: The questionnaire used in this research was made available online and included questions on demographics and physical activity. A total of 1.096 adult residents of Sao Paulo completed the questionnaire between July 8th and August 8th, 2020. Results: For individuals who were already physically active before the restrictions, a total of 55.8% of the sample kept insufficiently active during the quarantine. Factors such as education, working conditions, and direct relationship with Covid-19 care were associated with decreased leisure-time PA practice, impacting 57.6% of the sample, especially females. People with less formal education, those who possibly changed their routines to working from home, and those who were directly connected to Covid cases were not able to maintain a daily PA routine. Conclusion: The data presented here warn about the impacts of the pandemic on engagement in PA, suggesting the need for incentives from intersectoral public policies on sports, leisure, and health to perform these activities.


Assuntos
Humanos , Exercício Físico , Comportamento Sedentário , Distanciamento Físico , COVID-19/prevenção & controle , COVID-19/epidemiologia , Estudos Transversais , Inquéritos e Questionários
8.
Zootaxa ; 5052(4): 451-485, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34810860

RESUMO

Considering the growing threats to the biodiversity of small Caribbean islands (e.g., habitat loss and fragmentation, overexploitation, invasive species, and climate change), it is important to establish biodiversity inventories that serve as baselines for monitoring and evaluation of conservation efforts. In Barbados (West Indies), the most recent comprehensive taxonomic account of brachyuran crabs came from Rathbun (1921) reporting the specimens collected by the University of Iowa Barbados-Antigua Expedition in 1918. The present study fills the 100-year gap in knowledge by providing an updated taxonomic checklist of brachyuran crabs associated with semi-terrestrial and estuarine habitats in Barbados. A total of 245 specimens representing three superfamilies, six families, nine genera, and 13 species were collected over a period of 425 search-hours in twenty-seven sampling locations in semi-terrestrial and estuarine habitats of Barbados between September 2018 and November 2020. The families with the highest numbers of species identified were Gecarcinidae (3) and Portunidae (3), followed by Grapsidae (2), Sesarmidae (2), Ocypodidae (2), and Varunidae (1). The species Armases ricordi (H. Milne Edwards, 1853), Cyclograpsus integer H. Milne Edwards, 1837, and Callinectes sapidus Rathbun, 1896, are recorded here for the first time for Barbados.


Assuntos
Braquiúros , Infestações por Piolhos , Animais , Barbados , Ecossistema , Índias Ocidentais
9.
Zootaxa ; 4915(2): zootaxa.4915.2.11, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33756580

RESUMO

Hernáez et al. (2020) described a new species of ghost shrimp, Neocallichirus pinheiroi, from northeastern coast of Brazil, Western Atlantic. Although the description and figures presented by Hernáez et al. (2020) fully characterize the new species, the journal issue in which the description appeared was published online only, and the article in which N. pinheiroi appeared did not include a ZooBank registration number (LISD), required for validation of new names in electronic-only publications [vide Art. 8.5.3 of the amended Code of the International Commission on Zoological Nomenclature (ICZN, 1999, 2012)]. As result, the name Neocallichirus pinheiroi Hernáez, Windsor, Paula Santana, 2020, is not available according the International Code of Zoological Nomenclature (ICZN, 1999, 2012). Therefore, the present note serves to validate the name Neocallichirus pinheiroi by fulfilling the ICZN conditions for nomenclatural availability.


Assuntos
Decápodes , Animais
10.
Zootaxa ; 4920(1): zootaxa.4920.1.9, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33756681

RESUMO

Hernáez et al. (2020) described a new fossil species of ghost shrimp, Callichirus santensis, from the Upper Pleistocene Cananéia Formation, southeast Brazil. The article in which C. santensis† was originally proposed was published online only (Hernáez et al., 2020), but did not include a ZooBank registration number (LISD), required for validation of the new names in electronic-only publications [vide Art. 8.5.3 of the amended Code of the International Commission on Zoological Nomenclature (ICZN, 1999, 2012)]. Therefore, the present note serves to validate the name Callichirus santensis by fulfilling the ICZN conditions for nomenclatural availability.


Assuntos
Decápodes , Animais , Fósseis
11.
PeerJ ; 8: e9370, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32655990

RESUMO

A new species of freshwater crab, Fredius ibiapaba, is described and illustrated from a mid-altitude forested patch in Ipú (Ibiapaba plateau, Ceará, northeastern Brazil), between 635 to 782 m. The new species can be separated from its congeners by the morphology of its first gonopod: proximal half remarkably swollen, sloping abruptly downwards distally to a nearly right-angular shoulder; mesial lobe much smaller than cephalic spine; cephalic lobe moderately developed; auxiliary lobe lip, delimiting field of apical spines, protruded all the way to distal margin of auxiliary lobe. Comparative 16S rDNA sequencing used to infer the phylogenetic placement of Fredius ibiapaba n. sp. revealed that it is the sister taxon of F. reflexifrons, a species which occurs allopatrically in the Amazon and Atlantic basin's lowlands (<100 m). Fredius ibiapaba n. sp. and F. reflexifrons are highly dependent upon humidity and most probably were once part of an ancestral population living in a wide humid territory. Shrinking humid forests during several dry periods of the Tertiary and Quaternary likely have resulted in the fragmentation of the ancestral humid area and hence of the ancestral crab population. Fredius reflexifrons evolved and spread in a lowland, humid river basin (Amazon and Atlantic basins), whilst F. ibiapaba n. sp. evolved isolated on the top of a humid plateau. The two species are now separated by a vast intervening area occupied by the semiarid Caatinga.

12.
Sci Total Environ ; 738: 139787, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-32540602

RESUMO

Rare-earth elements have gained significant attention as they are currently widely used in high tech, chemical, and pharmaceutical industries. Here we used the fiddler crabs Leptuca leptodactyla as bioindicators to verify the presence of rare-earth elements in two mangrove areas of the Ubatuba, northern littoral of São Paulo state, Brazil. The specimens were collected in the mangrove areas of the Tavares River and Quiririm-Puruba river system, separated by season (dry and rainy). A total of 243 individuals were collected and analyzed. For determination and quantification of the elements we used the instrumental neutron activation analysis (INAA) technique. In both the dry and rainy season, the elements La, Ce, Sm, Eu, Tb, Yb and Sc were detected in samples of both mangroves, with La and Ce presenting higher concentrations. Samples from Tavares River mangrove had higher concentration levels of rare-earth elements than those of the Quiririm-Puruba river system. That is probably due to the central geographic position of the Tavares River in Ubatuba, which crosses a large portion of the city and receives a great amount of sewage. On the other hand, the Quiririm-Puruba river system has less anthropogenic inputs, thus, it receives much fewer rare-earth elements when compared to the Tavares River.


Assuntos
Braquiúros , Metais Terras Raras/análise , Animais , Brasil , Cidades , Biomarcadores Ambientais
13.
Zootaxa ; 4688(1): zootaxa.4688.1.6, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31719461

RESUMO

In this paper we report the first occurrence of two rare spider crabs (Majoidea) from Brazil, with additional morphological information based on material collected in the upper continental slope of the Potiguar Basin, northeast of Brazil. Lepteces ornatus Rathbun, 1893 (Epialtidae), originally described from the Gulf of Mexico and also reported from Uruguay, is now recorded from Brazilian waters (off Rio Grande do Norte), whereas Collodes leptocheles Rathbun, 1894 (Inachoididae) was considered for a long time as an endemic species of Gulf of Mexico and herein is being recorded for the first time in the Southern Atlantic.


Assuntos
Braquiúros , Decápodes , Animais , Brasil , Golfo do México , Uruguai
14.
Zookeys ; (825): 1-24, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30814903

RESUMO

Three new species and a new genus of majoid crabs from deep waters in the eastern Pacific are described and illustrated using morphological and molecular data. A new species of inachoidid, Collodesanartius sp. n. is described from Peru, which resembles C.tenuirostris Rathbun, 1893, in the general appearance of the carapace, but is distinguished by the details of tubercles on the carapace and thoracic sternum, proportions of the pereopod articles, and bathymetric distribution. A new epialtid, Nibiliamachala sp. n., is described from Ecuador; Nibilia A Milne-Edwards, 1878 has, until now, been considered to be monotypic, occurring only in the western Atlantic. This new species, from the eastern Pacific, closely resembles N.antilocapra (Stimpson, 1871) in the general morphology, but can be distinguished by the number of spines on the carapace and pereopods. Another epialtid, Solincaaulix gen. n. et sp. n, is establish for material collected from Ecuador and Peru, and can be easily identified from other taxa by the presence of a deep furrow between the very inflated branchial regions.

15.
Zootaxa ; 4418(3): 201-227, 2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-30313582

RESUMO

The genus Scyramathia A. Milne-Edwards, 1880 (type species Amathia carpenteri Norman in Wyville Thomson, 1873) is herein removed from the synonymy of Rochinia A. Milne-Edwards, 1875 (type species R. gracilipes A. Milne-Edwards, 1875) and a new genus, Minyorhyncha, is established for Amathia crassa A. Milne-Edwards, 1879, a species previously placed in the genus Rochinia. The genus Anamathia Smith, 1885 (type species Amathia rissoana Roux, 1828), widely regarded as a synonym of Rochinia, is confirmed as a valid genus. The morphological differences between Rochinia (as revealed by its type species), Anamathia, Scyramathia and Minyorhyncha are discussed and illustrated. The strong ontogenetic changes in Minyorhyncha crassa n. gen., n. comb. are also discussed and illustrated. Lectotypes are selected for Rochinia gracilipes A. Milne-Edwards, 1875, and Amathia agassizii Smith, 1882, a junior synonym of Minyorhyncha crassa n. gen., n. comb.


Assuntos
Distribuição Animal , Braquiúros , Estruturas Animais , Animais , Tamanho Corporal , Briozoários
16.
Zootaxa ; 4527(4): 494-500, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30651485

RESUMO

The first fossil Solenoceridae found from the Cretaceous (Aptian-Albian) is described in the Araripe Sedimentary basin, Priorhyncha feitosai n. gen. n. sp. The material was collected in the strata of the Romualdo Formation, municipality of Trindade, Pernambuco. Characters that permit placement of the new species in Solenoceridae are: a short, dorsally serrated rostrum; a marked cervical groove; and the presence of an antennal spine. Those characters are also diagnostic for Priorhyncha feitosai n. gen. n. sp. when compared to the other Dendrobranchiata shrimp described from this basin.


Assuntos
Decápodes , Fósseis , Animais , Brasil
17.
Appl Radiat Isot ; 120: 66-70, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27918918

RESUMO

Smilodon is a genus of big cats that lived from the early to the late Pleistocene in regions extending from North to South America. The fossil records of the "saber-toothed cats" are uneven, with some taxa being quite abundant in certain regions. In Brazil, Smilodon populator is a well-known species whose remains, although scarce in comparison to other large mammals, are found all across the country. In particular, there are multiple records of this species in the region of the Serra da Capivara National Park. This area was home to a rich Pleistocene-Holocene fauna, including many mammals. Here, we report on the Electron Spin Resonance dating of a Smilodon populator tooth found in "Toca de Cima dos Pilão", located in the surroundings of the Serra da Capivara National Park. The equivalent dose found after exponential fitting of dose-response curve was (2.7±0.3)x102Gy. Neutron Activation Analysis was used to determine the concentration of radioisotopes present in the sample and in the sediment to calculate the internal and external dose rates. The result of age found is 93±9ka, which confirmed the presence of this species in Serra da Capivara National Park in the late Pleistocene.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica/métodos , Felidae , Datação Radiométrica/métodos , Animais , Brasil , Felidae/anatomia & histologia , Fósseis/anatomia & histologia , História Antiga , Paleodontologia/métodos , Dente/anatomia & histologia
18.
Zootaxa ; 4184(3): zootaxa.4184.3.6, 2016 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-27988777

RESUMO

Stenocionops furcatus (Olivier, 1791) and S. coelatus (A. Milne-Edwards, 1878) have been treated either as subspecies or as species in their own right, but never as each other's synonyms. Compared to S. coelatus, S. furcatus has been regarded as having smoother dorsal surface carapace, shorter rostral spines, straighter and less divergent rostrum. and smaller interorbital width. These morphological differences between the two species, however, can be attributed to changes over ontogeny and, therefore, cannot be used as distinguishing characters. Adults of S. coelatus and S. furcatus can, however, be safely separated from each other by the presence in S. coelatus of a strong crenation on the anterior margin of the male sterno-abdominal cavity, which is absent in S. furcatus. A lectotype for S. coelatus is designated. The synonymy between S. furcatus, Cancer cornudo Herbst, 1804, and Chorinus armatus Randall, 1839, is confirmed based on the holotypes of the latter two species.


Assuntos
Braquiúros/classificação , Distribuição Animal , Exoesqueleto , Animais , Braquiúros/anatomia & histologia , Feminino , Masculino , Especificidade da Espécie
19.
Zootaxa ; 4171(2): 365-372, 2016 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-27701230

RESUMO

A new species of freshwater crab, Kingsleya attenboroughi n. sp., from the Arajara district, Ceará state, Brazil, is described and illustrated. The new species differs from congeners by having a short apical plate in the first gonopod, with anteriorly directed lobes and proximally angular; proximal lobe of the apical plate with conspicuous semicircular protuberance in mesial and sternal views; marginal process protruded, projecting mesially in sternal view and subquadrate in mesial view; and field of apical spines narrow, tapering distally, with small spines concentrated proximally. Opportunity is taken to illustrate K. gustavoi Magalhães, 2005, the closest allied species of K. attenboroughi n. sp. A key for the species of Kingsleya Ortmann, 1897 is provided.


Assuntos
Braquiúros/anatomia & histologia , Braquiúros/classificação , Animais , Brasil , Espécies em Perigo de Extinção , Feminino , Masculino
20.
Zootaxa ; 4052(3): 383-93, 2015 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-26701438

RESUMO

A new species of spider crab, Sunipea callistus, n. sp., from Cape Guardafui, Somali Republic, is described and illustrated. Sunipea indicus (Alcock, 1895) is also redescribed and figured. Sunipea callistus n. sp. differs from S. indicus in the structures of the carapace, third maxillipeds, thoracic sternum, male abdomen, and chelipeds. Despite a number of characteristics that separate both species, these differences are more pronounced in males and are less evident in females. A diagnosis for the genus is provided.


Assuntos
Braquiúros/anatomia & histologia , Braquiúros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Braquiúros/crescimento & desenvolvimento , Feminino , Masculino , Tamanho do Órgão
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...