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Parasites represent a large fraction of the world's biodiversity. They control host population sizes and contribute to ecosystem functioning. However, surveys on species diversity rarely include parasitic species. Bats often present traits favoring parasite diversity, such as large home ranges, long life spans, and large colonies. The most conspicuous bat parasites are the highly host‐specific, blood‐sucking bat flies (Diptera: Streblidae, Nycteribiidae). Recent studies have found a direct effect of habitat alteration on the abundance of bat species. We expected, therefore, that changes in the host community in response to anthropogenic habitat modification will also result in changes in the associated parasite community. We captured bats in three different habitats in Central Panama between 2013 and 2015. We recorded information on prevalence and intensity of bat fly parasitization of the seven most commonly captured bat species. Prevalence and intensity were both significantly influenced by roost type, abundance, and host sex and age. We found that habitat variables and matrix type significantly influenced the prevalence and intensity of parasitization, while the direction of the responses was host species‐ and parasite species‐specific. In general, roosting conditions and behavior of host bats appear to be fundamental in explaining changes in prevalence and intensity of parasitization between different habitat types, as bat flies are bound to the roost during their reproductive cycle. Habitat alterations affect next to the host community composition also the availability of possible roost structures as well as microclimatic conditions, which all three reflect in parasitization. Abstract in Spanish is available with online material.

Recently, network approaches have gained increasing popularity in studies of species interactions. These analyses provide important information about structural and functional organisation, as well as on the dynamics of species interactions. Common model systems for network studies include seed dispersal, pollination, and also parasite interactions. Bat flies (Diptera: Streblidae, Nycteribiidae) are obligate blood-sucking ectoparasites of bats. Resource partitioning allows multiple fly species to co-occur on a single host individual, making them an ideal model system for network analyses. Between 2013 and 2018 in Central Panama, 6528 bats from 53 species were examined for the presence of bat flies. Thereof, we collected a total of 6077 bat flies belonging to 52 species. The resulting interaction network showed a significantly higher specificity (H2' = 0.97) and modularity (Q = 0.78) than expected by chance, indicating a very high host specificity of the bat flies. To investigate parasite interactions in the context of host size, host abundance and roosting preferences, we pooled parasite identifications on genus level. The majority of our identified modules were associated with bats using persistent roosting structures. Neither host size nor host abundance appeared to affect module structure. Further, module structure appeared not to be host-phylogeny driven, instead modules were often composed of species known to share roosting structures. Their high host-specificity could put bat flies at risk of extinction in changing environments.

Parasitism is one of the most diverse and abundant modes of life, and of great ecological and evolutionary importance. Notwithstanding, large groups of parasites remain relatively understudied. One particularly unique form of parasitism is hyperparasitism, where a parasite is parasitized itself. Bats (Chiroptera) may be parasitized by bat flies (Diptera: Hippoboscoidea), obligate blood-sucking parasites, which in turn may be parasitized by hyperparasitic fungi, Laboulbeniales (Ascomycota: Laboulbeniomycetes). In this study, we present the global tritrophic associations among species within these groups and analyze their host specificity patterns. Bats, bat flies, and Laboulbeniales fungi are shown to form complex networks, and sixteen new associations are revealed. Bat flies are highly host-specific compared to Laboulbeniales. We discuss possible future avenues of study with regard to the dispersal of the fungi, abiotic factors influencing the parasite prevalence, and ecomorphology of the bat fly parasites., publishedVersion

Harmonia axyridis is an invasive alien ladybird in North America and Europe. Studies show that multiple natural enemies are using Ha. axyridis as a new host. However, thus far, no research has been undertaken to study the effects of simultaneous infections of multiple natural enemies on Ha. axyridis. We hypothesized that high thallus densities of the ectoparasitic fungus Hesperomyces virescens on a ladybird weaken the host’s defenses, thereby making it more susceptible to infection by other natural enemies. We examined mortality of the North American-native Olla v-nigrum and Ha. axyridis co-infected with He. virescens and an entomopathogenic fungus—either Beauveria bassiana or Metarhizium anisopliae. Laboratory assays revealed that He. virescens-infected O. v-nigrum individuals are more susceptible to entomopathogenic fungi, but Ha. axyridis does not suffer the same effects. This is in line with the enemy release hypothesis, which predicts that invasive alien species in new geographic areas experience reduced regulatory effects from natural enemies compared to native species. Considering our results, we can ask how He. virescens affects survival when confronted by other pathogens that previously had little impact on Ha. axyridis.

Surface nuclear magnetic resonance (SNMR) is a well-established technique for the hydrogeological characterization of the subsurface up to depths of about 150m. Recently, SNMR has been adapted to investigate also the shallow unsaturated zone with small surface loop setups. Due to the decreased volume, a pre-polarization (PP) field prior to the classical spin excitation is applied to enhance the measured response signal. Depending on the strength and orientation of the applied PP-field, the enhancement can often reach several orders of magnitude in the vicinity of the PP-loop. The theoretically achievable enhancement depends on the assumption of an adiabatic, i.e. perfect, switch-off of the corresponding PP-field. To study the effect of imperfect switch-off, we incorporate full spin dynamics simulations into the SNMR forward modeling. The affected subsurface volume strongly depends on the chosen PP switch-off ramp and the geometry of the loop setup. Due to the imperfect switch-off, the resulting SNMR sounding curves can have significantly decreased signal amplitudes. For comparison, the signal amplitudes of either a 1ms exponential or linear switch-off ramp are reduced by 17% and 65%, respectively. Disregarding this effect would therefore yield an underestimation of the corresponding subsurface water content of similar magnitude., preprint submitted to Geophysical Journal International

Summary We investigate the effect of the length scale of wetting heterogeneities, close to the length scale of a pore, on capillary pressure saturation (CPS) curves and the United States Bureau of Mines (USBM) and Amott-Harvey (AH) wettability indices. These macroscopic wettability indices are used to describe bulk rock wettability, because the local contact angle (the standard physical measure of wettability) in a sample is difficult to access and might vary within and between pores caused by changes in mineralogy and the surface coverage of organic materials. Our study combines laboratory experiments and full-scale fluid-dynamics simulations using the multiphase stochastic-rotation dynamics (SRDmc) model. Four model systems were created using monodisperse glass beads. The surface properties of the beads were modified so that one-half of the surface area in each system was strongly hydrophilic and the other half was hydrophobic. However, each system had a different length scale of wetting heterogeneity, ranging from a fraction of a bead diameter to two bead diameters. There is excellent agreement between the experimental and simulation results. All systems are classified as intermediate-wet on the basis of their AH and USBM indices. An examination of the capillary pressure curves shows that the opening of the stable hysteresis loop decreases monotonically as the length scale of the wetting heterogeneities is increased. Thus, our results suggest that macroscopic wettability indices could be used as indicators of ultimate recovery, but they are not suited to discriminate between the different flows that occur earlier in a mixed-wettability displacement process.

Bats are parasitized by numerous lineages of arthropods, of which bat flies (Diptera, Nycteribiidae and Streblidae) are the most conspicuous. Bat flies themselves can be parasitized by Laboulbeniales, fungal biotrophs of arthropods. This is known as hyperparasitism, a severely understudied phenomenon. Three genera of Laboulbeniales occur on bat flies: Arthrorhynchus on Nycteribiidae, Gloeandromyces and Nycteromyces on Streblidae. In this review we introduce the parasitic partners in this tripartite system and discuss their diversity, ecology, and specificity patterns, alongside some important life history traits. Furthermore, we cover recent advances in the study of the associations between bat flies and Laboulbeniales, which were neglected for decades. Among the most immediate needs for further studies are detailed tripartite field surveys. The vermin only teaze and pinch Their foes superior by an inch So, naturalists observe, a flea Has smaller fleas that on him prey; And these have smaller still to bite 'em, And so proceed ad infinitum. Jonathan Swift (On Poetry: A Rhapsody, 1733).

Bats and their ectoparasites are excellent model organisms to assess the conservation status of protected areas because both groups are speciose, and bats can be particularly affected by land use changes. The majority of bat studies conducted in Panama are clustered in protected areas around the Isthmus of Panama, while protected areas outside the Isthmus have not been studied in depth or remain largely unexplored. Coiba National Park is located on the Pacific coast of the country and is the fourth largest national park in Panama. Despite its distinct isolation from the mainland and the periodic dry spells it has undergone during the last 25,000 years, Coiba National Park has highly preserved forests. We provide the first study that assesses the structure of the bat assemblage of Coiba National Park, describe echolocation calls of some of its aerial insectivorous species, and contribute the first species list of ectoparasitic bat flies (Diptera: Streblidae). Using mist nets and acoustic monitoring techniques, we identified 30 bat species from 904 captures and 751 recordings. Artibeus jamaicensis and Carollia perspicillata were the most abundant species captured, while Myotis nigricans, Saccopteryx leptura and Molossus bondae were the most frequently recorded aerial insectivores. Associated with the bats we also identified 22 species of streblid flies, all representing new records for Coiba National Park. The host specificity was 98.2%, a high value compared to studies in other areas of Latin America. In total, we found eight new bat species for Coiba National Park, increasing the species list to 39, making it, with a rather limited study effort, the National Park with the fourth highest bat species richness recorded in Panama. We reckon that such levels of richness are correlated with the highly preserved forests of Coiba National Park.

Upscaling permeability of grid blocks is crucial for groundwater models. A novel upscaling method for three-dimensional fractured porous rocks is presented. The objective of the study was to compare this method with the commonly used Oda upscaling method and the volume averaging method. First, the multiple boundary method and its computational framework were defined for three-dimensional stochastic fracture networks. Then, the different upscaling methods were compared for a set of rotated fractures, for tortuous fractures, and for two discrete fracture networks. The results computed by the multiple boundary method are comparable with those of the other two methods and fit best the analytical solution for a set of rotated fractures. The errors in flow rate of the equivalent fracture model decrease when using the multiple boundary method. Furthermore, the errors of the equivalent fracture models increase from well-connected fracture networks to poorly connected ones. Finally, the diagonal components of the equivalent permeability tensors tend to follow a normal or log-normal distribution for the well-connected fracture network model with infinite fracture size. By contrast, they exhibit a power-law distribution for the poorly connected fracture network with multiple scale fractures. The study demonstrates the accuracy and the flexibility of the multiple boundary upscaling concept. This makes it attractive for being incorporated into any existing flow-based upscaling procedures, which helps in reducing the uncertainty of groundwater models.

Carbonate reservoirs form important exploration targets for the oil and gas industry in many parts of the world. This study aims to differentiate and quantify pore types and their relation to petrophysical properties in the Permo-Triassic Khuff Formation, a major carbonate reservoir in Oman. For that purpose, we have employed a number of laboratory techniques to test their applicability for the characterization of respective rock types. Consequently, a workflow has been established utilizing a combined analysis of petrographic and petrophysical methods which provide the best results for pore-system characterization. Micro-computed tomography (&micro, CT) analysis allows a representative 3D assessment of total porosity, pore connectivity, and effective porosity of the ooid-shoal facies but it cannot resolve the full pore-size spectrum of the highly microporous mud-/wackestone facies. In order to resolve the smallest pores, combined mercury injection capillary pressure (MICP), nuclear magnetic resonance (NMR), and BIB (broad ion beam)-SEM analyses allow covering a large pore size range from millimeter to nanometer scale. Combining these techniques, three different rock types with clearly discernible pore networks can be defined. Moldic porosity in combination with intercrystalline porosity results in the highest effective porosities and permeabilities in shoal facies. In back-shoal facies, dolomitization leads to low total porosity but well-connected and heterogeneously distributed vuggy and intercrystalline pores which improves permeability. Micro- and nanopores are present in all analyzed samples but their contribution to effective porosity depends on the textural context. Our results confirm that each individual rock type requires the application of appropriate laboratory techniques. Additionally, we observe a strong correlation between the inverse formation resistivity factor and permeability suggesting that pore connectivity is the dominating factor for permeability but not pore size. In the future, this relationship should be further investigated as it could potentially be used to predict permeability from wireline resistivity measured in the flushed zone close to the borehole wall.

Multi-color Stochastic Rotation Dynamics (SRDmc) has been introduced by Inoue et al. as a particle based simulation method to study the flow of emulsion droplets in non-wetting microchannels. In this work, we extend the multi-color method to also account for different wetting conditions. This is achieved by assigning the color information not only to fluid particles but also to virtual wall particles that are required to enforce proper no-slip boundary conditions. To extend the scope of the original SRDmc algorithm to e.g. immiscible two-phase flow with viscosity contrast we implement an angular momentum conserving scheme (SRDmc+). We perform extensive benchmark simulations to show that a mono-phase SRDmc fluid exhibits bulk properties identical to a standard SRD fluid and that SRDmc fluids are applicable to a wide range of immiscible two-phase flows. To quantify the adhesion of a SRDmc+ fluid in contact to the walls we measure the apparent contact angle from sessile droplets in mechanical equilibrium. For a further verification of our wettability implementation we compare the dewetting of a liquid film from a wetting stripe to experimental and numerical studies of interfacial morphologies on chemically structured surfaces., Comment: preprint submitted to Journal of Computational Physics

Deforestation and the conversion of forests to agricultural areas lead to habitat loss and often create highly fragmented landscapes. Permeability and quality of the surrounding matrix determine the connectivity of remaining forest remnants. For mobile species, such as bats, the matrix is not necessarily an entirely insurmountable obstacle. We studied the effects of fragmentation on New-World leaf-nosed bats (Phyllostomidae), a highly diverse keystone taxon in the Neotropics. Bats were assessed in two highly fragmented systems varying in matrix quality: Forested islands surrounded by the water (I) and forest fragments embedded in a matrix of small-scale agriculture (A) together with a continuous forest as control (C). In total, we recorded over 2 years 5176 captures. Observed species richness was highest in continuous forest. Fragmentation reduced in both fragmented landscapes the bat diversity and led to characteristic changes in the bat assemblage, with gleaning animalivorous phyllostomids being most affected. The responses of bats to fragmentation were found to be not only guild - but also species-specific within the guild, a fact easily overlooked or misinterpreted when focussing solely on diversity indices or the response of bat guilds alone. Forest remnants can support a relatively speciose bat fauna, due to the heterogeneity of the inter-fragment matrix. On forested islands, however, isolation processes lead to a decline in bat diversity, resulting in strongly impoverished bat assemblages favouring highly mobile species and habitat generalists. Conservation of the full local bat community of phyllostomids, including the vulnerable gleaning animalivorous phyllostomids, however, requires the protection of old-growth forests.

Multiphase flows in porous media are important in many natural and industrial processes. Pore-scale models for multiphase flows have seen rapid development in recent years and are becoming increasingly useful as predictive tools in both academic and industrial applications. However, quantitative comparisons between different pore-scale models, and between these models and experimental data, are lacking. Here, we perform an objective comparison of a variety of state-of-the-art pore-scale models, including lattice Boltzmann, stochastic rotation dynamics, volume-of-fluid, level-set, phase-field, and pore-network models. As the basis for this comparison, we use a dataset from recent microfluidic experiments with precisely controlled pore geometry and wettability conditions, which offers an unprecedented benchmarking opportunity. We compare the results of the 14 participating teams both qualitatively and quantitatively using several standard metrics, such as fractal dimension, finger width, and displacement efficiency. We find that no single method excels across all conditions and that thin films and corner flow present substantial modeling and computational challenges.

Harmonia axyridis is an invasive ladybird (Coleoptera, Coccinellidae) with the potential to outcompete native ladybird species in its invasive distribution area. It was introduced as a biological control agent in many countries but has also spread unintentionally in many others. Hesperomyces virescens (Ascomycota, Laboulbeniales) is a minute (200&ndash, 400 &micro, m in size) biotrophic fungus that infects over 30 species of ladybirds. The aim of this study was to evaluate whether the elytral colour pattern, size, and sex of Ha. axyridis affect infection by H. virescens. Coloration in Ha. axyridis has been linked to the presence of an antimicrobial alkaloid (harmonine). In fall 2016, we collected 763 Ha. axyridis individuals in Cambridge, Massaschusetts, of which 119 (16%) bore H. virescens fruiting bodies. We analyzed 160 individuals (80 infected, 80 uninfected) concerning the intensity of infection by H. virescens. Elytral sizes and colouration patterns were quantified using digital photography and analytical methods. Smaller ladybirds had a higher prevalence and higher intensity of parasitism. Additionally, male ladybirds bore more thalli compared to female ladybirds. Elytral colour patterns had an effect on neither prevalence nor intensity of infection by Laboulbeniales in our dataset, although we found a slight trend to higher intensity of parasitism in more melanic males. This suggests that the development of Laboulbeniales might be affected by certain insect alkaloids.

Bat flies (Streblidae) are diverse, obligate blood-feeding insects and probably the most conspicuous ectoparasites of bats. They show preferences for specific body regions on their host bat, which are reflected in behavioural characteristics. In this study, we corroborate the categorization of bat flies into three ecomorphological groups, focusing only on differences in hind leg morphology. As no detailed phylogeny of bat flies is available, it remains uncertain whether these morphological differences reflect the evolutionary history of bat flies or show convergent adaptations for the host habitat type. We show that the division of the host bat into three distinct habitats contributes to the avoidance of interspecific competition of bat fly species. Finally, we found evidence for density-dependent competition between species belonging to the same ecomorphological group.

The Darién province in eastern Panama is one of the most unexplored and biodiverse regions in the world. The Chucantí Nature Reserve, in Serranía de Majé, consists of a diverse tropical cloud forest ecosystem. The aim of this research was to explore and study host associations of a tripartite system of bats, ectoparasitic flies on bats (Diptera, Streblidae), and ectoparasitic fungi (Ascomycota, Laboulbeniales) that use bat flies as hosts. We captured bats at Chucantí, screened each bat for presence of bat flies, and screened collected bat flies for presence of Laboulbeniales. We mistnetted for 68 mistnet hours and captured 227 bats representing 17 species. We capturedMicronycteris schmidtorum, a species previously unreported in Darién. In addition, we encountered the rarely collectedPlatyrrhinus dorsalis, representing the westernmost report for this species. Of all captured bats, 148 carried bat flies (65%). The number of sampled bat flies was 437, representing 16 species. One species represents a new country record (Trichobius anducei) and five species represent first reports for Darién (Basilia anceps,Anatrichobius scorzai,Nycterophilia parnelli,T. johnsonae,T. parasiticus). All 74 bat fly species currently reported in Panama are presented in tabulated form. Of all screened bat flies, 30 bore Laboulbeniales fungi (7%). Based on both morphology and large ribosomal subunit (LSU) sequence data, we delimited 7 species of Laboulbeniales:Gloeandromyces nycteribiidarum(newly reported for Panama),G. pageanus,G. streblae,Nycteromyces streblidinus, and 3 undescribed species. Of the 30 infected flies, 21 wereTrichobius joblingi. This species was the only host on which we observed double infections of Laboulbeniales.

We present a newly developed high-pressure nuclear magnetic resonance (NMR) flow cell, which allows for the simultaneous determination of water saturation, effective gas permeability and NMR relaxation time distribution in two-phase fluid flow experiments. We introduce both the experimental setup and the experimental procedure on a tight Rotliegend sandstone sample. The initially fully water saturated sample is systematically drained by a stepwise increase of gas (Nitrogen) inlet pressure and the drainage process is continuously monitored by low field NMR relaxation measurements. After correction of the data for temperature fluctuations, the monitored changes in water saturation proved very accurate. The experimental procedure provides quantitative information about the total water saturation as well as about its distribution within the pore space at defined differential pressure conditions. Furthermore, the relationship between water saturation and relative (or effective) apparent permeability is directly determined.

Hypopigmentation disorders were reported in several bat species roosting in dark and sheltered roosts, but comparable records from open foliage roosts are rare. Here, we present three observations of non-albinistic hypopigmentation in two neotropical bat species. One extensively hypopigmented individual of

Background Bat flies (Streblidae and Nycteribiidae) are among the most specialized families of the order Diptera. Members of these two related families have an obligate ectoparasitic lifestyle on bats, and they are known disease vectors for their hosts. However, bat flies have their own ectoparasites: fungi of the order Laboulbeniales. In Europe, members of the Nycteribiidae are parasitized by four species belonging to the genus Arthrorhynchus. We carried out a systematic survey of the distribution and fungus-bat fly associations of the genus in central Europe (Hungary, Romania). Results We encountered the bat fly Nycteribia pedicularia and the fungus Arthrorhynchus eucampsipodae as new country records for Hungary. The following bat-bat fly associations are for the first time reported: Nycteribia kolenatii on Miniopterus schreibersii, Myotis blythii, Myotis capaccinii and Rhinolophus ferrumequinum; Penicillidia conspicua on Myotis daubentonii; and Phthiridium biarticulatum on Myotis capaccinii. Laboulbeniales infections were found on 45 of 1,494 screened bat flies (3.0%). We report two fungal species: Arthrorhynchus eucampsipodae on Nycteribia schmidlii, and A. nycteribiae on N. schmidlii, Penicillidia conspicua, and P. dufourii. Penicillidia conspicua was infected with Laboulbeniales most frequently (25%, n = 152), followed by N. schmidlii (3.1%, n = 159) and P. dufourii (2.0%, n = 102). Laboulbeniales seem to prefer female bat fly hosts to males. We think this might be due to a combination of factors: female bat flies have a longer life span, while during pregnancy female bat flies are significantly larger than males and accumulate an excess of fat reserves. Finally, ribosomal DNA sequences for A. nycteribiae are presented. Conclusions We screened ectoparasitic bat flies from Hungary and Romania for the presence of ectoparasitic Laboulbeniales fungi. Arthrorhynchus eucampsipodae and A. nycteribiae were found on three species of bat flies. This study extends geographical and host ranges of both bat flies and Laboulbeniales fungi. The sequence data generated in this work contribute to molecular phylogenetic studies of the order Laboulbeniales. Our survey shows a complex network of bats, bat flies and Laboulbeniales fungi, of which the hyperparasitic fungi are rare and species-poor. Their host insects, on the other hand, are relatively abundant and diverse. Electronic supplementary material The online version of this article (doi:10.1186/s13071-017-2022-y) contains supplementary material, which is available to authorized users.