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Macrofauna of sheltered and pocket beaches located in embayments, estuaries or landward of protective reefs has not been adequately assessed in beach ecology. In this setting, the concurrent role of large-scale morphodynamics and wave-exposure gradients in shaping biological patterns is still uncertain. To examine variations in community descriptors and the influence of physical factors on macrofauna, 12 sandy beaches on five islands within Sepetiba Bay (SE Brazil) were characterized in terms of beach morphodynamics and dimensions (length and width), such as geographical position relative to the bay mouth. A total of 80 species were collected and identified. Community descriptors of macrofauna responded to morphodynamics and exposure gradients. Increases in species richness, and abundance, from harsh reflective (coarse sands, steep slopes) to benign dissipative (fine sands, gentle slopes) beaches, and from the bay mouth (exposed beaches) towards the inner bay (sheltered beaches) were observed. Mollusks were the most abundant macrofaunal group, followed by crustaceans and polychaetes. Crustaceans dominated the beaches near the bay mouth, whereas mollusks were more abundant on the beaches farther from the bay mouth. Canonical correspondence analysis showed that the degree of exposure, distance from the bay mouth, beach index, and beach length and width significantly affected the macrofauna distribution and abundance, creating an environmental gradient along Sepetiba Bay. Differences in macrofauna composition among the beaches studied were associated with beach length and width. In this sense, spatial variation of macrofauna among beaches can be a function of intertidal area. These results indicate that community characteristics in the sandy beaches studied are affected by several physical characteristics, but also by other factors that are affected by coastal processes. [ABSTRACT FROM AUTHOR]

A crustacean survey was made in Sepetiba bay, Rio de Janeiro state, southeastern Brazil. Twelve sandy beaches were sampled on five islands in this embayment. A total of 3024 individuals were collected, belonging to 21 species, which are grouped in 16 families, seven infraorders, seven suborders, and four orders. Isopods, followed by amphipods and tanaids, showed the highest abundance, amounting to over 92% of the dominance of crustaceans. The main species were Excirolana armata, Excirolana braziliensis (isopods), Atlantorchestoidea brasiliensis (amphipod), and Monokalliapseudes schubarti (tanaid), which together accounted about 80% of crustaceans of the beaches studied. Excirolana braziliensis had the highest frequency. The majority of species found are typical of sandy beaches, with large spatial distribution. [ABSTRACT FROM AUTHOR]

The reproductive biology and population dynamics of the cirolanid isopod Excirolana armata (Dana, 1853) were analysed through monthly samples from December 2003 to November 2005 on Una beach, São Paulo state (24° S), in Southeastern Brazil. Sampling was performed along three transects established from the base of foredunes to the waterline. On Una beach, E.  armata showed continuous reproduction with higher abundances of ovigerous females in winter and spring (July–November) with a higher peak of juveniles in spring (November 2004). The fecundity ranged from 2 to 18 eggs/embryos per female, depending on the female length. The incubation period was estimated as 2 months. The life span of males and females was nearly 1 year. The short life span and the high energetic expenditure inherent to reproduction with maternal care, probably kept females from producing more than one brood in their lifetime. When comparing the population of E. armata on Una beach (24° S) with populations in Southern Brazil (32° S), Uruguay (34° S) and Argentina (36° S), it was verified that several biological population traits (length of the smallest juvenile, length of the largest individual, length of the smallest and largest ovigerous females, range of fecundity and life span) tended to increase at higher latitudes, whereas other traits (instantaneous rate of mortality and the curvature parameter of von Bertalanffy growth function) tended to decrease. However, comparing E. armata on Una beach (24° S) with a population situated at a close latitude (25° S), unexpected differences in relation to population structure and to growth demonstrated and reinforced the importance of density-dependent factors over life history traits of E. armata on dissipative beaches. [ABSTRACT FROM AUTHOR]

The population dynamics and secondary production of the cirolanid isopod Excirolana braziliensis are compared between two distinct sandy beaches. Monthly sampling from June 1998 through July 2000 was carried out at Grumari (a reflective beach with coarse sand and steeper slope) and Restinga da Marambaia (an intermediate beach with fine sand and moderate slope), both located in Rio de Janeiro State (23° 5), southeastern Brazil. Sampling was conducted according to a systematic design in which two transects (fixed 500 meters apart) were established, each with 10 equally spaced sampling strata. From each stratum, five replicates (0.04 square meters) were taken. Highest population abundances were observed in spring and summer on both beaches. The beaches differed significantly in physical parameters and the characteristics of their inhabitant populations: (1) Grumari Beach had a steeper slope, coarse sands, and a short swash period; (2) the abundance of total population, fecundity at length, and egg production potential were higher at Restinga da Marambaia; and (3) individual growth of males was higher at Grumari. Mean length at sexual maturity (L50%), mortality, growth of females, secondary production, and mean annual biomass did not show significant differences between beaches. Variations in population parameters of E. braziliensis might be regulated by phenotypic adjustment to local conditions, optimizing fitness, and especially enabling species to adapt to different physical conditions. [ABSTRACT FROM AUTHOR]

Demographic and life-history attributes of the mole crab Emerita brasiliensis were analysed along 2700 km of the Atlantic coast of South America, including sandy beaches at the southernmost limit (Uruguay) and at the core of its geographical range (Brazil). Population features varied markedly within this range and exhibited systematic geographical patterns of variation. Abundance significantly increased from temperate to subtropical beaches, and the same held true for the asymptotic weight of males. Conversely, length at maturity and asymptotic weight of females increased from subtropical to temperate beaches, being inversely related to sea water temperature. Macroecological patterns in abundance and body weight showed the first large-scale evidence of scaling of population density to body size for a sandy beach population. Mortality rates (both sexes) followed a nonlinear increase from low-density temperate beaches to high-density subtropical beaches. The effect of habitat quality and availability could explain discontinuities in the species distribution within its range, and also differential responses in life-history attributes at a local scale. Asymmetries and converse latitudinal trends between sexes suggest that there is not a single general factor determining large-scale patterns in life-history traits of this species. Our results reinforce the view that density-dependent and environmental factors operating together regulate sandy beach populations. The need to develop macroecological studies in sandy beach ecology is highlighted, as knowledge acquired from local to large spatial scales throws light on population structure and regulation mechanisms. [ABSTRACT FROM AUTHOR]

The embryonic development and reproductive strategy of Pseudorchestoidea brasiliensis, a talitrid amphipod of the supra- and midlittoral zones, were investigated by combining collections from June 1993 to May 1995 at Prainha, Rio de Janeiro (23°05'S and 43°25'W). The initial stage of embryonic development (I) was most frequent and was seen in about 70% of ovigerous females. Mean embryo volume in the final stage of development was almost twice that in the initial stage. Brood mortality between embryonic Stages I and IV was estimated at 11.42%. Multivoltism, continuous reproduction, low brood mortality (may be caused by better parental care with offspring) and the larger number of females than males in the population were indicated as compensating factors for the low fecundity observed in P. brasiliensis. [ABSTRACT FROM AUTHOR]

Cholesteatomas are frequent middle ear benign tumors of unknown etiology. Infectious agents have been considered as possible contributing factors in the pathogenesis of cholesteatomas. Aiming to investigate the presence of respiratory viruses in primary cholesteatoma tissues, 26 formalin-fixed paraffin-embedded primary cholesteatoma tissues obtained from patients seen at the of the Clinical Hospital of the University of São Paulo School of Medicine, in Ribeirão Preto, Brazil were tested by real-time polymerase chain reaction (PCR). Considering the PCR results, 35% of the tissues were positive for human rhinovirus (HRV), 15.3% for human enterovirus (EV), 3.8% for human metapneumovirus (HMPV), and 3.8% for human bocavirus (HBoV). Serial immunohistochemistry for virus antigens and cell surface markers evidenced that the viruses were associated with fibroblasts, dendritic cells, macrophages, B lymphocytes, CD4 + , and CD8 + T lymphocytes. These findings indicate for the first time the presence of active respiratory virus infection in primary cholesteatoma tissues, suggesting that persisting virus infection in the middle could play a role in the pathogenesis and evolution of cholesteatomas., (© 2021 Wiley Periodicals LLC.)

Intense human use and high construction density in coastal areas are stressors to sandy beaches. Pollution by marine debris is a major problem on beaches worldwide. This study pioneered an assessment of marine debris characterization over time on beaches with different levels of access. In two periods and seasons, marine debris was sampled on nine sandy beaches of Rio de Janeiro, grouped by levels of access. The general marine debris density has decreased over time, accompanied by an improvement in public cleaning mechanisms. The most important predictor for the majority of marine debris items is related to accessibility; beaches with restricted access showed a reduction in the abundance of most items. High marine debris densities, even on beaches with restricted access, showed that all evaluated beaches can be sinks for marine debris circulating in marine waters. Beach cleaning strategy improvements will be inefficient unless integrated marine debris management is implemented., (Copyright © 2021 Elsevier Ltd. All rights reserved.)