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Simple Summary: The flat mite family Tenuipalpidae includes 41 genera and more than 1100 species worldwide, and is considered one of the most important families of phytophagous mites. The Ultratenuipalpus is a small genus with 25 known species present in almost all zoogeographic regions. Here, a new species Ultratenuipalpus parameekeri Castro, Ochoa & Feres sp. nov. is described from specimens collected on ferns from Brazil. It represents the first species of the genus described from the country. The type species of the genus Ultratenuipalpus meekeri (De Leon) is redescribed based on types and newly collected material from Mexico. Highly detailed low-temperature scanning electron image (LT-SEM) micrographs and DNA barcodes are provided for both species. The taxonomy of the genus Ultratenuipalpus and the ontogenetic additions of leg setae are discussed. Species of the genus Ultratenuipalpus bear a broad subquadrate propodosoma with many large, flattened, lanceolate to ovate dorsal setae. They also bear some plesiomorphic character states, such as the presence of three pairs of ventral ps setae. Here, we describe Ultratenuipalpus parameekeri Castro, Ochoa & Feres sp. nov. based on adult females, males, and immatures, collected on ferns from Brazil. We also re-describe Ultratenuipalpus meekeri (De Leon), the type species of the genus, based on types and newly collected material from Mexico, and include additional novel data (e.g., dorsal and ventral ornamentation, leg chaetotaxy, and setal measurements) in a standardized form. We include highly detailed images obtained using LT-SEM, accompanied by DNA barcodes, for both species. The ontogenetic additions of leg chaetotaxy are presented and discussed. [ABSTRACT FROM AUTHOR]

Species of the genus Ultratenuipalpus bear a broad subquadrate propodosoma with many large, flattened, lanceolate to ovate dorsal setae. They also bear some plesiomorphic character states, such as the presence of three pairs of ventral ps setae. Here, we describe Ultratenuipalpus parameekeri Castro, Ochoa & Feres sp. nov. based on adult females, males, and immatures, collected on ferns from Brazil. We also re-describe Ultratenuipalpus meekeri (De Leon), the type species of the genus, based on types and newly collected material from Mexico, and include additional novel data (e.g., dorsal and ventral ornamentation, leg chaetotaxy, and setal measurements) in a standardized form. We include highly detailed images obtained using LT-SEM, accompanied by DNA barcodes, for both species. The ontogenetic additions of leg chaetotaxy are presented and discussed.

Low temperature scanning electron microscopy (LT-SEM) has revealed anatomical details suggesting that Osperalycus and Gordialycus (Acariformes: Nematalycidae) have an unusual feeding apparatus that is hypothesized to be specialized for feeding on the fluid contents of small microorganisms (diameter < 5 μm). Both mite genera have a feeding strategy that appears to involve picking up small microorganisms and placing them onto the subcapitulum for puncturing. However, they have slightly different variants of the same basic rupturing mechanism. Whereas Gordialycus has evolved expansive and convergent rutella to hold the microorganisms in place while pushing chelicerae into them, Osperalycus has evolved a pouch into which a microorganism is inserted. The rutella reinforce this pouch while the chelicerae break up the microorganism. Both types of mouthpart apparatus seem to be adapted to minimize waste, an appropriate specialization given the organically impoverished habitats in which these mites live. [ABSTRACT FROM AUTHOR]

Previous research on the locomotion of the Nematalycidae has only been undertaken on Gordialycus, which is by far the most elongated genus of the family. Gordialycus is dependent on an unusual form of peristalsis to move around. It was not known whether the genera of Nematalycidae with shorter bodies also used this mode of locomotion. Our videographic recordings of Osperalycus did not reveal peristalsis. Instead, this mite appears to move around the mineral regolith via the expansion and constriction of the metapodosomal and genital region, allowing greater versatility in the way that the annular regions contract and extend. This type of locomotion would enable relatively short bodied nematalycids to anchor themselves into secure positions before extending their anterior regions through tight spaces. Low-temperature scanning electron micrographs show that the short bodied genera have integumental features that appear to be associated with this mode of locomotion. Peristalsis is almost certainly a more derived form of locomotion that is an adaptation to the unusually long body form of Gordialycus. [ABSTRACT FROM AUTHOR]

Three new species of Tarsonemidae, Daidalotarsonemus oliveirai Rezende, Lofego & Ochoa, sp. n., Excelsotarsonemus caravelis Rezende, Lofego & Ochoa, sp. n. and Excelsotarsonemus tupi Rezende, Lofego & Ochoa, sp. n. are described and illustrated. Measurements for these species are provided, as well as drawings, phase contrast (PC), differential interference contrast (DIC) and low temperature scanning electron microscopy (LT-SEM) micrographs. Some characters, which have not been used or clearly understood, are described herein. Biological, ecological and agricultural aspects about the role of these species in the rainforest and its surrounding environment are briefly discussed. [ABSTRACT FROM AUTHOR]

Trachymolgus purpureus Fisher & Dowling sp. n. is described from the Ozark highlands of North America. A diversity of imaging techniques are used to illustrate the species including low-temperature scanning electron microscopy (LT-SEM), stereomicrography, compound light micrography, and digitally created line drawings. Developmental stages (larva, nymphs, and adult) and morphology are illustrated and discussed, and terminological corrections are suggested. Trachymolgus recki Gomelauri, 1961 is regarded as being described from tritonymphs. A key to Trachymolgus is presented. [ABSTRACT FROM AUTHOR]

Abstract: Hydrocolloids are added in ice-creams and frozen desserts to produce smooth texture and protect the product during its storage. The high-pressure freezing techniques also aimed to enhance product qualities. In this work, both the hydrocolloid and the high-pressure processing actions are combined. A 0.3% (w/w) of guar gum (viscous solution) or of locust bean gum plus xanthan gum (gel) was mixed in sucrose solutions (16% w/w) to analyze whether water mobility affected ice crystal formation. Sucrose solutions with or without hydrocolloids were frozen by high-pressure assisted freezing (HPAF) at 100MPa and by high-pressure shift freezing (HPSF) from 210MPa to 0.1 and 100MPa, to compare their effects on the ice crystal characteristics. Ice crystal sizes were determined from images obtained by low temperature scanning microscopy (LT-SEM). Ice crystals were smaller after HPSF than after HPAF, due to greater supercooling following expansion and to shorter phase transition times. As regards the hydrocolloids, ice crystals were smaller when the mixture of locust bean and xanthan gums were added irrespective of the freezing method. The formation of a gel-like structure at ambient temperature strengthened by a cryo-gelation effect in the frozen state may limit water molecule diffusion and ice crystal growth. [Copyright &y& Elsevier]

Abstract: Four oil-in-water emulsions, stabilized by native or pre-denatured whey proteins in the absence or presence of casein, were whipped at −5°C and stored at −30°C for several weeks. The microstructure of these whipped-frozen emulsions, which differed by their protein content, were observed by low-temperature scanning electron microscopy (LT-SEM), and transmission electron microscopy (TEM) following freeze-substitution and low-temperature embedding. Fat globule aggregation and adsorbed protein content in whipped-frozen emulsions were determined after application of thawing, dilution or centrifugation. Micrographs indicated that in aerated products, partial replacement of native whey proteins by pre-denatured whey proteins or casein introduced (i) more homogeneity in air bubble size, (ii) more attachment of fat globules to their air–serum interface, and (iii) fat globules in the continuous matrix that were in closer contact with each other. These differences in the microstructures of whipped-frozen emulsions were attributed to differing surface heterogeneity of adsorbed protein particles to fat globule interfaces. [Copyright &y& Elsevier]