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We performed a macroscopic and radiological inspection in a set of bones belonging to the fossil mammal assemblage of Zabelê Paleontological Site (Late Pleistocene-Northgrippian), in northeastern Brazil. Radiological analyzes were carried out using conventional X-ray and X-ray microtomography (µCT) equipment. This study revealed four different types of diseases (calcium pyrophosphate deposition disease – CPPD, infection, trauma and tendon avulsion) restricted to the giant ground sloth E. laurillardi (5.36% of MNI) and in an indeterminate mammal species. The apparent restriction to E. laurillardi is related to taphonomic/palaeoecological bias. The data expand the number of occurrences of diseases in xenarthras species. [ABSTRACT FROM AUTHOR]

Aulacothrips dictyotus Hood, 1952 (Thysanoptera: Heterothripidae) is a highly specific ectoparasite, which infests nymphs and adults of Aetalion reticulatum (Linnaeus, 1758) (Hemiptera: Aetalionidae) in South America. However, nothing is known about the consequences of this remarkable interaction to the hemipterans, which also exhibit mutualistic associations with ants. In this study, we test the hypothesis that Au. dictyotus directly affects Ae. reticulatum behaviour by comparing ethograms of thrips‐infected and uninfected aetalionids. An analysis of 15 behavioural acts showed significant differences in the behaviour of Ae. reticulatum between these two experimental groups. Hemipterans exhibited dramatic changes in behaviour under Au. dictyotus presence, and the frequencies of some behaviours related to locomotion were statistically higher in individuals with thrips, as well as kicking movements using the hind legs. Moreover, infected aetalionids showed higher frequencies of grooming behaviour, which seems to have some efficacy in detaching Au. dictyotus. We demonstrated that thrips presence disturb host foraging behaviour and induces unusual behavioural acts that are likely to be very costly to hosts. Our results suggest that thrips parasitism constitutes an important selective force for hemipterans and that its effects can influence host individuals, the aggregation and potentially the mutualistic interaction with ants. [ABSTRACT FROM AUTHOR]

The rice stalk stink bug, Tibraca limbativentris Stål, damages plant stalks while feeding, making it one of the most important rice pests in South America. Because the feeding behavior of T. limbativentris has not yet been studied in rice, we investigated T. limbativentris stylet penetration (probing) in rice stalks. A waveform library was created using the new AC-DC EPG monitor with different levels of input resistance (Ri). Six different waveforms were recorded and correlated via histological studies and grouped into three phases: non-probing waveforms (Z and Np), pathway waveforms (Tl1), and ingestion waveforms (Tl2 and Tl3). The Z waveform was observed when the stink bug was standing still on the plant surface, Np when the stink bug was walking on plant surface, Tl1 was associated with stylet insertion and deep penetration into the plant tissue, and Tl2 when the stink bug was feeding on xylem vessels. The Tl3 waveform was associated with the rupture of stalk cells and was divided into two subtypes (Tl3a and Tl3b). The Tl3a waveform probably represents cell laceration with combined enzymatic maceration of stalk tissues, while Tl3b represents a short ingestion period of macerated tissues. Tibraca limbativentris uses two strategies to feed on rice stalks: a salivary sheath for feeding on xylem vessels and cell rupture (laceration and maceration) for feeding on parenchyma cells. Our study provides crucial benchmark definitions of waveforms. Future studies can now compare effects of treatments on stink bug feeding, to ultimately improve management of this pest in rice. [ABSTRACT FROM AUTHOR]

Isoetes dubsii sp. nov. and I. santacruzensis sp. nov., two new species from lowland areas in South America, are described, illustrated and compared to similar species. Isoetes dubsii can be distinguished from other species of the Brazilian Pantanal wetlands by a set of characters including leaves that are long, flexuous and trigonal in transverse section, tri-lobate stems, rudimentary velum, pustulate megaspores of 310-390 µm diameter and laesurae of the megaspore at least four times wider than high. Isoetes santacruzensis has flexuous, filiform leaves, 0.4-0.8 mm wide at mid length and reaching up to 15 cm long, black or reddish-black sporangia, sclerified phyllopodia and sparsely verrucate megaspores of 320-390 µm in diameter. We also include a key for species from the Brazilian Pantanal wetlands and Bolivia and spore images for all species that are discussed. Isoetes dubsii and I. santacruzensis are only known from their type localities and they may deserve special attention concerning their conservation status. However, based on our current knowledge on these species and according to IUCN Red List criteria, they are assessed here as data deficient (DD). [ABSTRACT FROM AUTHOR]

Sporothrix brasiliensis is the main agent of zoonotic sporotrichosis transmitted by domestic cats in South America. In humans, sporotrichosis commonly presents with cutaneous or lymphocutaneous lesions, and in cats, with multiple ulcerated skin lesions associated with enlarged lymph nodes and respiratory signs. Fungal virulence factors may affect the clinical presentation of the mycoses. Sporothrix spp. present some virulence factors. This study aims to compare 24 S. brasiliensis strains from 12 familiar outbreaks of cat-to-human transmitted sporotrichosis. Fungal growth in different substrates, thermotolerance, resistance to oxidative stress, and production of enzymes were evaluated. An invertebrate model of experimental infection was used to compare the virulence of the strains. The strains grew well on glucose and N-acetyl-D-glucosamine but poorly on lactate. Their thermotolerance was moderate to high. All strains were susceptible to hydrogen peroxide, and the majority produced hemolysins but not phospholipase and esterase. There was no significant difference in the putative virulence-associated factors studied among the different hosts. Moreover, strains isolated from a human and a cat from four familiar outbreaks presented a very similar profile of expression of these factors, reinforcing the zoonotic transmission of S. brasiliensis in Brazil and demonstrating the plasticity of this species in the production of virulence factors. [ABSTRACT FROM AUTHOR]

Oceanic heat sources disturb the atmosphere, which, to come back to its initial state, disperses waves. These waves affect the climate in remote regions, characterizing the teleconnection patterns. In this study, we describe eight teleconnection patterns that affect South America climate: the El Niño–Southern Oscillation (ENSO), the Pacific Decadal Oscillation (PDO), the Atlantic Multidecadal Oscillation (AMO), the Tropical Atlantic Dipole (TAD), the South Atlantic Dipole (SAD), the Southern Annular Mode (SAM), the Madden–Julian Oscillation (MJO), and the Indian Ocean Dipole (IOD). Precipitation and winds at 850‐hPa anomalies, considering these teleconnection patterns in ENSO neutral periods, are also presented. Overall, southeastern South America and the north sector of the North and Northeast regions of Brazil are the most affected areas by the teleconnection patterns. In general, there is a precipitation dipole pattern between these regions during each teleconnection pattern. [ABSTRACT FROM AUTHOR]

The incorrect author name is: Jéssica S. de Guedes The correct author name is: Jéssica de S. Guedes The author group has been updated above and the original article [[1]] has been corrected. B Correction: Immun Ageing 19, 57 (2022) b B https://doi.org/10.1186/s12979-022-00310-y b Following publication of the original article [[1]], the authors identified an error in the author name of Jéssica de S. Guedes. Mateus V. de Castro, Monize V. R. Silva, Erick C. Castelli and Keity S. Santos contributed equally to this work. [Extracted from the article]