In the early 20th century, Alphonse Meunier described "Papulifères" as a group of enigmatic forms of unknown taxonomic affinity characterized by possessing a hyaline pimple, a "papula". In the early 1980's Papulifères were equated with cysts of tintinnid ciliates. The most conspicuous forms, the large Fusopsis, have been widely found, and are now known to resemble the cyst of a certain species of oligotrich ciliate (i.e., Cyrtostrombidium boreale). Thus today, Papulifère forms are often assumed to be cysts of oligotrich ciliates. Here we report on 26 Papulifère forms, of more or less distinct morphologies, found in the plankton of the Chukchi Sea. We found forms resembling some of those described by Meunier, and recorded here for the first time since Meunier's reports, and others that do not resemble any of Meunier's Papulifères. Here, we first review the literature on Papulifères, then we present the surprising variety of forms we found in Chukchi Sea, and for some, we provide for the first time data on morphological variability. With this report we have expanded the catalogue of observed Papulifère forms and documented variability in the dimensions of some morphotypes. However, we urge caution in assigning a ciliate species name to any given Papulifère form in the absence of corroborating data. There is a need for observational and/or sequence-based data to elucidate the identity of Papulifère forms.

Malaria diagnosis continues to be one of the most important steps in the cycle of control specially in endemic countries with low parasitic load infections. Loop-mediated isothermal amplification (LAMP) and ultrasensitive PCR (Us-PCR) are two promising candidates for malaria diagnosis. A cross sectional study performed at King Faisal Hospital, Taif KSA involved patients suffering from signs and symptoms suggesting of malaria, 35 blood samples diagnosed by Nested Multiplex PCR as a reference method (13 P. falciparum, 17 P. vivax, 3 mixed P. falciparum and P. vivax) plus two negative controls were selected to be included in this study to analyse the performance of two LAMP methods (LAMP OptiGene® and LAMP WarmStart®) and two ultrasensitive PCRs (Us-PCR TARE-2 and Us-PCR Var-ATS). LAMP OptiGene® and LAMP WarmStart® performances were identical and better than the performance of Us PCR TARE 2 and Us-PCR var-ATS for P. falciparum, achieving 93.75% sensitivity, 100% specificity and 97.17% accuracy versus 87.5% sensitivity, 100% specificity and 94.29% accuracy for the Us PCR TARE 2 and 81.25% sensitivity, 94.74% specificity and 88.57% accuracy for the Us PCR var-ATS respectively. In P. vivax diagnosis LAMP OptiGene® performed excellently with 100% sensitivity, specificity, and accuracy while LAMP WarmStart® and Us-PCR Cox1 achieved 100% sensitivity, specificity 93.33% and 97.14% accuracy. The study results highlighted the benefits of using LAMP techniques for field diagnosis of malaria in different settings where the need for a more sensitive and reliable molecular tool is mandatory but at the same time removing the high cost, long turnaround time and the need of highly specialized trained technicians to perform more sophisticated molecular techniques.

We investigated the diversity of testate amoebae in an urban stream located within the Igarapé São Francisco Environmental Protection Area in Acre, northern Brazil, during the dry season, and evaluated the factors mediating the structure of this protist community. We collected 108 water samples for the analysis of the testate amoeba community and the limnological variables at six sampling points on the stream, between July and September 2018. We used a Redundancy Analysis (RDA) to verify the influence of environmental variables on the protist community. We recorded 76 species of testate amoebae from eight families, with most records from the families Difflugiidae, Arcellidae, Centropydae and Netzeliidae. More than half (49) of the species were recorded in Acre for the first time. The abundance of the amoebae of the family Trigonopiridae was regulated by the dissolved oxygen concentrations and the pH, while that of the Netzeliidae, Difflugiidae and Lesquereusidae was influenced by the pH, chloride concentrations, and the depth and transparency of the water. In the case of the family Arcellidae, abundance was determined by the turbidity and transparency of the water and the nitrate concentrations, while that of Centropyxis sp. was associated with the concentrations of thermotolerant coliforms. These findings indicate that, while the São Francisco stream is subject to anthropogenic impacts, it still presents adequate conditions for these organisms in some of its stretches. The abundance of these amoebae was influenced primarily by the productivity of the system, as indicated by the high protist densities recorded in the areas in which primary productivity was highest. These findings support the use of these protists in studies that investigate the most appropriate indicator organisms that respond to anthropogenic impacts and shifts in environmental quality.The results of the present study demonstrated the importance of this aquatic ecosystem for the biodiversity of the study area, and the need to further expand our knowledge on the adaptations and interactions of the aquatic communities of the Amazon region.

Resting cyst formation is a crucial process of cryptobiosis in protists. In colpodid ciliates, cyst formation is accompanied by large-scale morphological changes such as changes of cell shape, resorption of cilia, and formation of a cyst wall; additionally, the cell cycle is arrested. These changes provide acquired tolerance against environmental stresses. During cyst formation, mitochondrial membrane potential is reduced and the level of the ATP synthase beta chain is suppressed, strongly indicating that metabolism has ceased. Here, however, we show that ATP levels are elevated during the initial phases of encystment implying that metabolism may not be completely suppressed. This finding suggests another aspect of resting cyst formation that is not applicable to cryptobiosis.