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Abordamos la visión reduccionista de la salud, que gran parte de la población restringe a la inversión en infraestructura sanitaria, profesionales y medicamentos, sin considerar la interconexión con el medioambiente. La Organización Mundial de la Salud (OMS) advierte que un alto porcentaje de enfermedades son consecuencia del cambio climático, la contaminación y la destrucción del entorno natural (entre otros), que supondrían más de 250.000 muertes adicionales anuales. A pesar de esta alarmante situación, la sociedad permanece en gran medida inconsciente. Científicos y profesionales de la salud han alertado durante décadas sobre las consecuencias de la degradación ambiental para la salud humana: por ejemplo, muchos medicamentos provienen principalmente de plantas y animales que habitan en ecosistemas amenazados. El concepto de One Health destaca la interconexión entre la salud humana, animal y ambiental. La pandemia de covid-19 ejemplifica esta conexión. La crisis mostró la necesidad de un cambio de rumbo, pero la reacción fue temporal y se ha vuelto a priorizar la tecnología sobre el respeto por la naturaleza. El texto concluye que la responsabilidad de cambiar este enfoque recae tanto en los dirigentes políticos como en la propia sociedad. Se han de adoptar modelos de desarrollo respetuosos con el medioambiente para evitar el colapso y garantizar un futuro saludable. La adopción del concepto de One Health es esencial para este cambio., We address the reductionist view of health: that a major part of the population restricts to the investment in healthcare infrastructure, professionals and medications, without taking into account the interconnection with the environment. The World Health Organization (WHO) is warning that a high proportion of diseases are a consequence of the global climate change, the contamination, and the destruction of the natural environment (among others), which would represent over 250,000 additional deaths per year. Despite this alarming scenario, society remains unaware to a high extent. Scientists and health professionals have been warning for decades about the consequences of environmental degradation for human health; for example, many medications are primarily based on plants and animals living in threatened ecosystems. The One Health concept highlights the interconnection between human, animal and environmental health. The COVID-19 pandemic is an example of this connection. The crisis showed the need for a change in direction, but this reaction was temporary, and technology has been prioritized again over respect for nature. The conclusion of this text is that the responsibility for this change of approach lies both in political leaders as in the society itself. Models of development that respect the environment must be adopted, to prevent collapse and guarantee a healthy future. The adoption of the One Health concept is essential for this change.

Insect communities are facing contrasting responses due to global change. However, knowledge on impacts of communities’ reorganizations is scarce. Network approaches could help to envision community changes in different environmental scenarios. Saproxylic beetles were selected to examine long-term variations in insect interaction/diversity patterns and their vulnerability to global change. We evaluated interannual differences in network patterns in the tree hollow–saproxylic beetle interaction using absolute samplings over an 11-year interval in three Mediterranean woodland types. We explored saproxylic communities’ vulnerability to microhabitat loss via simulated extinctions and by recreating threat scenarios based on decreasing microhabitat suitability. Although temporal diversity patterns varied between woodland types, network descriptors showed an interaction decline. The temporal beta-diversity of interactions depended more on interaction than on species turnover. Interaction and diversity temporal shifts promoted less specialized and more vulnerable networks, which is particularly worrisome in the riparian woodland. Network procedures evidenced that saproxylic communities are more vulnerable today than 11 years ago irrespective of whether species richness increased or decreased, and the situation could worsen in the future depending on tree hollow suitability. Network approaches were useful for predicting saproxylic communities’ vulnerability across temporal scenarios and, thus, for providing valuable information for management and conservation programs.

Forests of the Mediterranean Basin provide a wide range of provisioning and regulating services that are currently jeopardised by land-use change. Although many ecosystem services are mediated by insects, most of the studies that have focused on how to enhance diversity in traditionally managed forests are about plants and vertebrates. Quercus pyrenaica woodlands of the Western Iberian Peninsula constitute a scenario in which traditional human practices (i.e., extensive livestock grazing, pollarding, firewood, forest thinning, etc.), and their progressive abandonment, have generated differences in landscape that affect habitat and microhabitat structures. We used saproxylic beetles (deadwood-dependent species) as biological indicators because they are the most diverse taxa and provide important ecosystem services related to deadwood decomposition, forest pest control and pollination. We modelled the response of two taxonomic (species richness and abundance), one ecological (species diversity of order 1) and two functional (functional richness and redundancy) diversity metrics to the environmental variables that result from traditional management or its abandonment at habitat and microhabitat levels. We included 16 explanatory variables related to forest structure, tree microhabitats and abiotic factors, which were grouped into eight principal components. Linear regression was the best fitting model for data. The resulting models were used to perform diversity predictions in different scenarios. We found that abandonment of some traditional forest management activities in the Mediterranean Region reduced taxonomic saproxylic beetle diversity, which may be further aggravated by climate change. We suggest minimal management actions to improve taxonomic and ecological saproxylic beetle diversity related to habitat and tree management (i.e., maintenance of >20% scrub coverage, >20 m3/ha of deadwood on soil and >20 hollow trees/ha). However, actions that boost saproxylic

Background: Flight performance and dispersal behaviour can differ between sexes, resulting in sex-biased dispersal. The primary sex ratio of populations may also explain dispersal bias between sexes, as this bias may evolve with the primary sex ratio to reduce intrasexual competition. Although dispersal bias between sexes is relevant to population dynamics, there are few studies on sex-biased dispersal in insects. We studied the flight performance and dispersal behaviour of seven saproxylic beetle species associated with tree hollows from a sex perspective. We also analysed the possible coevolution of flight performance with the primary sex ratio. Methods: Wing loading and wing aspect ratio were used as measures of the flight performance of species and sexes. Dispersal behaviour was explored by analysing the frequency of each sex in interception traps versus the primary sex ratio obtained by tree hollow emergence traps using contingency tables and posthoc standardized residuals. A more active flight behaviour was expected for the sex with higher capture frequency in the interception traps. To explore the causes of flight performance bias between sexes, we searched for possible correlations between wing loading or wing aspect ratio and primary sex ratio using Pearson’s correlation coefficient. Results: Wing loading and wing aspect ratio differed between species and sexes, with flight performance being higher in males than in females for four of the seven species analysed. Dispersal behaviour and flight performance matched in the case of Elater ferrugineus; males showed higher flight performance and were the most collected sex in the interception traps (more active flyers). In contrast, the higher flight activity of Cetonia carthami aurataeformis females was not correlated with a higher flight performance than that of males. Moreover, we found that a bias in the primary sex ratio towards females is often correlated with a decrease in female flight performance. Conclus

Forests of the Mediterranean Basin provide a wide range of provisioning and regulating services that are currently jeopardised by land-use change. Although many ecosystem services are mediated by insects, most of the studies that have focused on how to enhance diversity in traditionally managed forests are about plants and vertebrates. Quercus pyrenaica woodlands of the Western Iberian Peninsula constitute a scenario in which traditional human practices (i.e., extensive livestock grazing, pollarding, firewood, forest thinning, etc.), and their progressive abandonment, have generated differences in landscape that affect habitat and microhabitat structures. We used saproxylic beetles (deadwood-dependent species) as biological indicators because they are the most diverse taxa and provide important ecosystem services related to deadwood decomposition, forest pest control and pollination. We modelled the response of two taxonomic (species richness and abundance), one ecological (species diversity of order 1) and two functional (functional richness and redundancy) diversity metrics to the environmental variables that result from traditional management or its abandonment at habitat and microhabitat levels. We included 16 explanatory variables related to forest structure, tree microhabitats and abiotic factors, which were grouped into eight principal components. Linear regression was the best fitting model for data. The resulting models were used to perform diversity predictions in different scenarios. We found that abandonment of some traditional forest management activities in the Mediterranean Region reduced taxonomic saproxylic beetle diversity, which may be further aggravated by climate change. We suggest minimal management actions to improve taxonomic and ecological saproxylic beetle diversity related to habitat and tree management (i.e., maintenance of >20% scrub coverage, >20 m3/ha of deadwood on soil and >20 hollow trees/ha). However, actions that boost saproxylic

Las oquedades de los árboles y la madera muerta en suelo son microhábitats clave para la diversidad saproxílica. En este trabajo se estudia la fauna de dermápteros asociada a ambos microhábitats y se analiza la distribución espacio-temporal de sus especies. El muestreo se ha realizado mediante el uso de trampas de emergencia y trampas de ventana, en 4 áreas naturales de la provincia de Salamanca dominadas por árboles maduros de Quercus. Se capturaron 955 individuos de tres especies. Sin embargo, el 96% de las capturas pertenecieron a una especie del complejo Forficula auricularia: F. dentata. Las elevadas abundancias de esta especie en madera muerta en suelo, oquedades de los árboles y en el dosel arbóreo podrían resaltar la importancia funcional de las especies del complejo de F. auricularia como depredadoras en estos microhábitats, por lo que podrían considerarse especies saproxílicas facultativas. Dos endemismos ibéricos, Mesochelidura bolivari y Forficula iberica, fueron también ocasionalmente capturados. Sin embargo, la ausencia de ninfas para estas dos especies nos indica que no usan estos microhábitats como lugar de reproducción. La distribución temporal de las especies mostró dinámicas poblacionales distintas, presentando un pico de actividad en primavera-verano para F. dentata, frente al máximo de actividad en otoño-invierno de las dos especies menos abundantes, lo que podría evitar una posible competencia con la especie dominante. Finalmente, cabe destacar que estos peculiares microhábitats que ofrecen los árboles vivos y la madera muerta en suelo, son relevantes en distinto grado para las especies de dermápteros., Tree hollows and downed logs are key microhabitats for saproxylic diversity. In this work the fauna of Dermaptera associated to both microhabitats was studied and the spatial-temporal distribution of the species was analysed. The sampling was carried out through the use of emergence traps and window traps in 4 natural areas of the Salamanca province dominated by mature trees of Quercus. In total, 955 individuals belonging to three species were collected. However, 96% of the captures belonged to a species of the Forficula auricularia complex: F. dentata. The great abundance of this species in downed logs, tree hollows and tree canopy could highlight the functional importance of the F. auricularia species complex as predators in these microhabitats, thus could be considered facultative saproxylic species. Moreover, two Iberian endemism, Mesochelidura bolivari and Forficula iberica were occasionally also captured. However, the absence of nymphs of these two species indicates us that they do not use these microhabitats for reproduction. The temporal distribution of the species showed different population dynamics, a peak of activity in spring-summer occurred for F. dentata, in contrast with the maximum activity in autumn-winter of the other less abundant species, which could be avoiding a possible competence with the dominant species. Finally, it should be emphasised that these peculiar microhabitats offered by trees and downed logs are relevant in different degree for the species of Dermaptera.

This paper focuses on the role of aphidophagous syrphids in different strategies of Integrated Pest Control in greenhouse crops. Southeastern Spain is the world area with the highest production of organic products. Our scientific experience and field experimentation in the use of syrphids for control of pest aphids, show compatibility and effectiveness on the combined use of syrphids with other strategies commonly used in integrated pest control.

1. Despite the fact that insects are suffering a global decline, little is known about the extent to which species loss affects functional diversity. Thus, to understand the relationship between taxonomic and functional diversity metrics, we focused on saproxylic beetles, which perform vital functions in forest ecosystems. 2. Beetles were collected monthly for a year using flight interception traps placed in three protected areas of mature evergreen Mediterranean Quercus forests. Five morphological traits, one phenological trait, and one physiological surrogate trait were measured, and trophic guild identities were determined. Two taxonomic and six functional metrics were assessed to determine their relationships. 3. Taxonomic and functional diversity patterns, as well as trait patterns, differed depending on the protected areas, as they were influenced by habitat and microhabitat characteristics. Generally, a high number of species tended to support high values of functional richness, but did not ensure high values of functional redundancy, thus affecting the resilience of communities. 4. A 5% of species loss strongly affected the functional redundancy of communities, making them more vulnerable. Functional richness, however, was not affected, since it was associated with a high number of redundant species. Thus, the way species loss affected communities is highly dependent on the presence of rare or redundant species. 5. Taxonomic and functional diversity metrics should be used as complementary tools for conservation purposes. In this way, the comparative analysis of taxonomic and functional patterns may help to predict the vulnerability of saproxylic assemblages to changes or disturbances.

Canthon (Canthon) cyanellus LeConte, 1859 es un escarabajo rodador necrófago con amplia distribución en los bosques tropicales del nuevo mundo. Su historia taxonómica es compleja y agrupa a especies que fueron designadas anteriormente y que fueron agrupadas en una sola especie por Halffter en 1961. Las poblaciones de esta especie son morfológicamente muy similares. La gran variación de coloración cuticular a nivel geográfico de esta especie ha sido empleada para definir a diferentes subespecies i.e., Canthon cyanellus cyanellus, C. cyanellus violetae Halffter, 1961 y C. cyanellus sallei Harold, 1853 sensu Halffter, 1961, por lo que a esta especie se le puede designar como el complejo Canthon cyanellus. Para entender los procesos evolutivos que han conducido a la diversificación y actual distribución del complejo “cyanellus” en el Neotrópico, se planteó estudiar su estructura filogeográfica en la Zona de Transición Mexicana (ZTM) empleando dos marcadores moleculares mitocondriales (16S y COI) y uno nuclear (ITS2). Las características de la genitalia del macho en escarabajos de este género han tenido valor taxonómico para separar subespecies o especies próximas; sin embargo, en C. cyanellus no han sido analizadas considerando la variación geográfica. Por esta razón, posteriormente se analizó la variabilidad de la morfología de la genitalia masculina (i.e. edeago: falobase y parameros) a nivel geográfico considerando su distribución en el Neotrópico. Ambos enfoques, el genético y morfológico, se compararon con la taxonomía del grupo. La longitud de los tres loci (i.e. ITS2 + 16S + COI) analizados fue de 2,196 pb con un total de 76 haplotipos. La diversidad genética fue más baja para ITS2, que para los loci mitocondriales. Los análisis de SAMOVA, ANOVAs y las redes de haplotipos indicaron alta estructura genética asociada con la distribución geográfica de las poblaciones. El cronograma inferido con los tres marcadores moleculares combinados indicó que los eventos de cla

This paper focuses on the role of aphidophagous syrphids in different strategies of Integrated Pest Control in greenhouse crops. Southeastern Spain is the world area with the highest production of organic products. Our scientific experience and field experimentation in the use of syrphids for control of pest aphids, show compatibility and effectiveness on the combined use of syrphids with other strategies commonly used in integrated pest control.

1. Despite the fact that insects are suffering a global decline, little is known about the extent to which species loss affects functional diversity. Thus, to understand the relationship between taxonomic and functional diversity metrics, we focused on saproxylic beetles, which perform vital functions in forest ecosystems. 2. Beetles were collected monthly for a year using flight interception traps placed in three protected areas of mature evergreen Mediterranean Quercus forests. Five morphological traits, one phenological trait, and one physiological surrogate trait were measured, and trophic guild identities were determined. Two taxonomic and six functional metrics were assessed to determine their relationships. 3. Taxonomic and functional diversity patterns, as well as trait patterns, differed depending on the protected areas, as they were influenced by habitat and microhabitat characteristics. Generally, a high number of species tended to support high values of functional richness, but did not ensure high values of functional redundancy, thus affecting the resilience of communities. 4. A 5% of species loss strongly affected the functional redundancy of communities, making them more vulnerable. Functional richness, however, was not affected, since it was associated with a high number of redundant species. Thus, the way species loss affected communities is highly dependent on the presence of rare or redundant species. 5. Taxonomic and functional diversity metrics should be used as complementary tools for conservation purposes. In this way, the comparative analysis of taxonomic and functional patterns may help to predict the vulnerability of saproxylic assemblages to changes or disturbances.

Las oquedades de los árboles y la madera muerta en suelo son microhábitats clave para la diversidad saproxílica. En este trabajo se estudia la fauna de dermápteros asociada a ambos microhábitats y se analiza la distribución espacio-temporal de sus especies. El muestreo se ha realizado mediante el uso de trampas de emergencia y trampas de ventana, en 4 áreas naturales de la provincia de Salamanca dominadas por árboles maduros de Quercus. Se capturaron 955 individuos de tres especies. Sin embargo, el 96% de las capturas pertenecieron a una especie del complejo Forficula auricularia: F. dentata. Las elevadas abundancias de esta especie en madera muerta en suelo, oquedades de los árboles y en el dosel arbóreo podrían resaltar la importancia funcional de las especies del complejo de F. auricularia como depredadoras en estos microhábitats, por lo que podrían considerarse especies saproxílicas facultativas. Dos endemismos ibéricos, Mesochelidura bolivari y Forficula iberica, fueron también ocasionalmente capturados. Sin embargo, la ausencia de ninfas para estas dos especies nos indica que no usan estos microhábitats como lugar de reproducción. La distribución temporal de las especies mostró dinámicas poblacionales distintas, presentando un pico de actividad en primavera-verano para F. dentata, frente al máximo de actividad en otoño-invierno de las dos especies menos abundantes, lo que podría evitar una posible competencia con la especie dominante. Finalmente, cabe destacar que estos peculiares microhábitats que ofrecen los árboles vivos y la madera muerta en suelo, son relevantes en distinto grado para las especies de dermápteros., Tree hollows and downed logs are key microhabitats for saproxylic diversity. In this work the fauna of Dermaptera associated to both microhabitats was studied and the spatial-temporal distribution of the species was analysed. The sampling was carried out through the use of emergence traps and window traps in 4 natural areas of the Salamanca province dominated by mature trees of Quercus. In total, 955 individuals belonging to three species were collected. However, 96% of the captures belonged to a species of the Forficula auricularia complex: F. dentata. The great abundance of this species in downed logs, tree hollows and tree canopy could highlight the functional importance of the F. auricularia species complex as predators in these microhabitats, thus could be considered facultative saproxylic species. Moreover, two Iberian endemism, Mesochelidura bolivari and Forficula iberica were occasionally also captured. However, the absence of nymphs of these two species indicates us that they do not use these microhabitats for reproduction. The temporal distribution of the species showed different population dynamics, a peak of activity in spring-summer occurred for F. dentata, in contrast with the maximum activity in autumn-winter of the other less abundant species, which could be avoiding a possible competence with the dominant species. Finally, it should be emphasised that these peculiar microhabitats offered by trees and downed logs are relevant in different degree for the species of Dermaptera.

Tree hollows and downed logs are key microhabitats for saproxylic diversity. In this work the fauna of Dermaptera associated to both microhabitats was studied and the spatial-temporal distribution of the species was analysed. The sampling was carried out through the use of emergence traps and window traps in 4 natural areas of the Salamanca province dominated by mature trees of Quercus. In total, 955 individuals belonging to three species were collected. However, 96% of the captures belonged to a species of the Forficula auricularia complex: F. dentata. The great abundance of this species in downed logs, tree hollows and tree canopy could highlight the functional importance of the F. auricularia species complex as predators in these microhabitats, thus could be considered facultative saproxylic species. Moreover, two Iberian endemism, Mesochelidura bolivari and Forficula iberica were occasionally also captured. However, the absence of nymphs of these two species indicates us that they do not use these microhabitats for reproduction. The temporal distribution of the species showed different population dynamics, a peak of activity in spring-summer occurred for F. dentata, in contrast with the maximum activity in autumn-winter of the other less abundant species, which could be avoiding a possible competence with the dominant species. Finally, it should be emphasised that these peculiar microhabitats offered by trees and downed logs are relevant in different degree for the species of Dermaptera.

Los coleópteros saproxílicos son aquellos que, al menos en una parte de su ciclo vital, dependen directamente o indirectamente de la madera muerta o moribunda y de otros organismos saproxílicos, como hongos habitantes de la madera. La madera muerta o moribunda posee una gran diversidad de formas y orígenes (árboles muertos, caídos o en pie, árboles moribundos, ramas muertas, caídas o no, oquedades o heridas en árboles sanos o no, o restos de troncos como tocones y cortezas), por lo que los organismos saproxílicos, son de gran importancia en los ecosistemas, sobre todo en los forestales. Sin embargo, y a pesar de ello están gravemente amenazados por cambios en sus hábitats y microhábitats, principalmente causados por el ser humano. Aunque tradicionalmente la biodiversidad de los ecosistemas ha sido medida a través de la identidad y abundancia de especies, en las últimas décadas se ha desarrollado otro modo medir la biodiversidad basándose en los rasgos funcionales de las especies, que ha sido conocido como diversidad funcional. El objetivo general de esta tesis es profundizar en el conocimiento de las comunidades de escarabajos saproxílicos en áreas protegidas y bien conservadas de la Península Ibérica a través del estudio de su diversidad taxonómica y funcional, con el fin de comprender qué variables y mecanismos pueden estar detrás de su biodiversidad. Con el fin de lograr este objetivo se realizó un muestreo sistemático de las comunidades de escarabajos saproxílicos en tres áreas protegidas de España (parque nacional de Cabañeros, parque natural de Font Roja y parque natural de Sierra Espadán) usando para ello tres tipos de trampas (trampas de intersección en vuelo o trampas de ventana, trampas de emergencia en oquedades, y trampas de emergencia en troncos en suelo). La incorporación funcional al estudio de estas comunidades ha permitido aseverar que el número de especies o la abundancia de estas no provee suficiente información sobre dichas comunidades, por lo qu

We analysed the genetic divergence and morphology of the aedeagus (i.e. phallobase and parameres) in Canthon cyanellus at different geographical levels. The results from both approaches were compared with the current taxonomic assignment of the C. cyanellus complex, which includes three subspecies. We found a high variation in all the morphological characters of the aedeagus in the populations analysed; the morphometric variation was not geographically structured, either by population or by region. The genealogical analysis indicates a significant genetic structure that does not match either the morphological variation in the male genitalia or the previous subspecific taxonomic classification. Our results suggest that the morphological variation of the aedeagus is seemingly not an isolating reproductive barrier and that the intra- and interpopulation morphological variability of the aedeagus in the C. cyanellus complex does not permit the division into several species. We suggest that other evolutionary forces, such as genetic drift and sexual selection, have influenced the evolution of the male genitalia and the incipient differentiation of this species complex.

Understanding how biodiversity is distributed across geographical and environmental gradients is a main goal of diversity sciences. However, since ecosystem processes are linked to variation in functional traits of the biota, examining functional beta diversity is particularly important. Our objective was to analyze the taxonomic and functional beta diversity patterns of saproxylic beetle assemblages in evergreen Quercus forest of Spain. We tested whether environmental or geographical distance had a greater influence on taxonomic and functional beta diversity, and if both measures of beta diversity were affected by the same environmental variables. We used 45 flight interception traps distributed in three protected areas over a 12-mo period to sample saproxylic beetles. We measured 13 environmental variables around each trap and the geographical distance between traps. For functional composition, we used 12 functional traits from four functional groups (morphological, phenological, trophic, and a surrogate of physiological). Our results showed that environmental differences between areas influenced the taxonomic and functional beta diversity components (replacement and loss/gain) but in different ways. While replacement components (higher for taxonomic composition) increased with environmental distance, the loss or gain components (higher for functional composition) remained constant, indicating that species replacement mostly involved functionally redundant species. Besides, environmental variables influencing both taxonomic and functional composition were strongly dependent on each area. In conclusion, in well-preserved Mediterranean forests, environmental filtering determines the taxonomic and functional composition of saproxylic beetle assemblages, by favoring species replacement but filtering species traits.

We explored the dependence of some Cetoniidae species on saproxylic environments and microhabitats in a Mediterranean oak forest by analyzing species collected using different kinds of traps—log emergence, hollow emergence, and interception traps—and the sex ratio of the species in each trap. Comparing the sex ratio of the species collected via emergence versus interception was useful to unravel the degree of dependence on saproxylic microhabitats. Among the species studied, Cetonia aurataeformis Curti, 1913 (Coleoptera: Cetoniidae) was the only obligate tree hollow inhabitant. Special attention should thus be paid to the maintenance of tree hollows for the species’ conservation in Mediterranean forests. A gradient of dependence on tree hollows was established from the more dependent Protaetia (Potosia) cuprea (Fabricius, 1775) (Coleoptera: Cetoniidae) and Protaetia (Potosia) opaca (Fabricius, 1787) (Coleoptera: Cetoniidae) to the less dependent Protaetia (Netocia) morio (Fabricius, 1781) (Coleoptera: Cetoniidae). All the latter species can be considered facultatively dependent, to varying degrees, on tree hollows. By contrast, the saproxylic affinity of Protaetia (Netocia) oblonga (Gory and Percheron, 1833) (Coleoptera: Cetoniidae), Tropinota squalida (Scopoli, 1783) (Coleoptera: Cetoniidae) and Oxythyrea funesta (Poda, 1761) (Coleoptera: Cetoniidae) was doubtful. Generally, the sex ratio of the studied species was female-biased. A possible explanation may be local male competition for females, suggesting the Cetoniinae is a female world. However, the range of difference in the female-biased sex ratio among species suggests it is important to explore other possible causes, such as differences in dispersal abilities.

Correction to: Scientific Reports https://doi.org/10.1038/s41598-020-58408-6, published online 30 January 2020

Saproxylic beetles depend on diverse microhabitats that are exploited by different species assemblages. We focused on anlyse the functional trait patterns and functional diversity components of two main assemblages that were collected with window traps (WTs) and hollow emergence traps (HETs) respectively, between three protected areas of the Iberian Peninsula. For that we measured phenological, physiological, morphological, and ecological traits. Results showed that the main microhabitats exploited by each assemblage (WT and HET) constrain most of the morphological traits and trophic guilds. In addition, relative elytra length and predator guild, together with adult activity period, responded to differences at the habitat level (among study areas). HET assemblages were less taxonomically diverse but more functionally diverse than those of WTs, enhancing the functional relevance of tree hollows. Additionally, niche filtering dominated WT assemblages, which were characterised by a narrower functional space and a higher redundancy. In contrast, in the HET assemblages the coexistence of functionally dissimilar species is driven by the niche heterogeneity. HET and WT assemblages differed in the functional space occupied by each within areas, but both assemblages reflected coincident patterns among areas that pointed to a reduction of functional space with management.

We analysed the genetic divergence and morphology of the aedeagus (i.e. phallobase and parameres) in Canthon cyanellus at different geographical levels. The results from both approaches were compared with the current taxonomic assignment of the C. cyanellus complex, which includes three subspecies. We found a high variation in all the morphological characters of the aedeagus in the populations analysed; the morphometric variation was not geographically structured, either by population or by region. The genealogical analysis indicates a significant genetic structure that does not match either the morphological variation in the male genitalia or the previous subspecific taxonomic classification. Our results suggest that the morphological variation of the aedeagus is seemingly not an isolating reproductive barrier and that the intra- and interpopulation morphological variability of the aedeagus in the C. cyanellus complex does not permit the division into several species. We suggest that other evolutionary forces, such as genetic drift and sexual selection, have influenced the evolution of the male genitalia and the incipient differentiation of this species complex.

Understanding how biodiversity is distributed across geographical and environmental gradients is a main goal of diversity sciences. However, since ecosystem processes are linked to variation in functional traits of the biota, examining functional beta diversity is particularly important. Our objective was to analyze the taxonomic and functional beta diversity patterns of saproxylic beetle assemblages in evergreen Quercus forest of Spain. We tested whether environmental or geographical distance had a greater influence on taxonomic and functional beta diversity, and if both measures of beta diversity were affected by the same environmental variables. We used 45 flight interception traps distributed in three protected areas over a 12-mo period to sample saproxylic beetles. We measured 13 environmental variables around each trap and the geographical distance between traps. For functional composition, we used 12 functional traits from four functional groups (morphological, phenological, trophic, and a surrogate of physiological). Our results showed that environmental differences between areas influenced the taxonomic and functional beta diversity components (replacement and loss/gain) but in different ways. While replacement components (higher for taxonomic composition) increased with environmental distance, the loss or gain components (higher for functional composition) remained constant, indicating that species replacement mostly involved functionally redundant species. Besides, environmental variables influencing both taxonomic and functional composition were strongly dependent on each area. In conclusion, in well-preserved Mediterranean forests, environmental filtering determines the taxonomic and functional composition of saproxylic beetle assemblages, by favoring species replacement but filtering species traits.

Correction to: Scientific Reports https://doi.org/10.1038/s41598-020-58408-6, published online 30 January 2020

We explored the dependence of some Cetoniidae species on saproxylic environments and microhabitats in a Mediterranean oak forest by analyzing species collected using different kinds of traps—log emergence, hollow emergence, and interception traps—and the sex ratio of the species in each trap. Comparing the sex ratio of the species collected via emergence versus interception was useful to unravel the degree of dependence on saproxylic microhabitats. Among the species studied, Cetonia aurataeformis Curti, 1913 (Coleoptera: Cetoniidae) was the only obligate tree hollow inhabitant. Special attention should thus be paid to the maintenance of tree hollows for the species’ conservation in Mediterranean forests. A gradient of dependence on tree hollows was established from the more dependent Protaetia (Potosia) cuprea (Fabricius, 1775) (Coleoptera: Cetoniidae) and Protaetia (Potosia) opaca (Fabricius, 1787) (Coleoptera: Cetoniidae) to the less dependent Protaetia (Netocia) morio (Fabricius, 1781) (Coleoptera: Cetoniidae). All the latter species can be considered facultatively dependent, to varying degrees, on tree hollows. By contrast, the saproxylic affinity of Protaetia (Netocia) oblonga (Gory and Percheron, 1833) (Coleoptera: Cetoniidae), Tropinota squalida (Scopoli, 1783) (Coleoptera: Cetoniidae) and Oxythyrea funesta (Poda, 1761) (Coleoptera: Cetoniidae) was doubtful. Generally, the sex ratio of the studied species was female-biased. A possible explanation may be local male competition for females, suggesting the Cetoniinae is a female world. However, the range of difference in the female-biased sex ratio among species suggests it is important to explore other possible causes, such as differences in dispersal abilities.

Saproxylic beetles depend on diverse microhabitats that are exploited by different species assemblages. We focused on anlyse the functional trait patterns and functional diversity components of two main assemblages that were collected with window traps (WTs) and hollow emergence traps (HETs) respectively, between three protected areas of the Iberian Peninsula. For that we measured phenological, physiological, morphological, and ecological traits. Results showed that the main microhabitats exploited by each assemblage (WT and HET) constrain most of the morphological traits and trophic guilds. In addition, relative elytra length and predator guild, together with adult activity period, responded to differences at the habitat level (among study areas). HET assemblages were less taxonomically diverse but more functionally diverse than those of WTs, enhancing the functional relevance of tree hollows. Additionally, niche filtering dominated WT assemblages, which were characterised by a narrower functional space and a higher redundancy. In contrast, in the HET assemblages the coexistence of functionally dissimilar species is driven by the niche heterogeneity. HET and WT assemblages differed in the functional space occupied by each within areas, but both assemblages reflected coincident patterns among areas that pointed to a reduction of functional space with management.

El estudio de la fauna de coleópteros saproxílicos en siete espacios protegidos de la península ibérica, ha permitido obtener datos sobre la abundancia y fenología del coleóptero xilomicetófago Platypus cylindrus, especie considerada plaga en numerosos países de la cuenca mediterránea. De todas las especies arbóreas muestreadas, su mayor abundancia ha sido detectada en los bosques de Quercus suber del Parque Natural de la Sierra de Espadán, particularmente en la localidad más antropizada y con actual manejo del corcho. En el resto de los espacios protegidos y especies arbóreas su presencia ha sido moderada. En el Parque Natural de la Sierra de Espadán P. cylindrus está activo durante un amplio rango de meses, con mayores abundancias entre agosto y septiembre, coincidiendo con lo observado en otras poblaciones de climas cálidos., During the last years, sampling of the saproxylic coleopteran communities in seven protected areas in the Iberian Peninsula, has allowed to obtain data of the abundance and phenology of the xylomycetophagous Platypus cylindrus, which is considered plague in some countries of Mediterranean basin. Between all the arboreal species sampled, the largest presence of P. cylindrus has been detected in the Quercus suber forests of the Natural Park of Sierra Espadán, particularly in the most anthropized and with cork management locality. In the rest of the protected areas and arboreal species sampled its presence has been moderate. In the Natural Park of Sierra Espadán, P. cylindrus has been active during a wide range of months, with the biggest abundances between August and September, similarly to other populations of warm climates.

Los insectos saproxílicos, que dependen de la presencia de madera muerta y/o en descomposición, de hongos de la madera, o bien de la presencia de otros organismos saproxílicos, en algún momento de su ciclo vital, desempeñan una función clave para el correcto funcionamiento de los ecosistemas de bosque, actuando como recicladores de los nutrientes contenidos en la madera en descomposición. La diversidad de insectos saproxílicos, y más concretamente de coleópteros, así como la estructura de los ensambles que conforman, se encuentran condicionadas por una serie de variables de carácter físico, químico y biótico. Comprender cómo este amplio conjunto de variables afecta a los patrones espacio-temporales de las comunidades, resulta esencial a la hora de elaborar estrategias de manejo de los ecosistemas, que permitan preservar este tipo de fauna, en muchas ocasiones, amenazada. Con este marco de fondo, el objetivo general de esta tesis doctoral reside en analizar el conjunto de factores ambientales que afectan a la diversidad y a la distribución espacio-temporal de los ensambles de coleópteros saproxílicos que habitan los bosques mediterráneos de roble melojo ubicados en el oeste de la península ibérica para, de este modo, poder proponer una serie de directrices a seguir, a la hora de manejar este tipo de ecosistemas. Este objetivo general se divide en una serie de objetivos específicos, cada uno de los cuales ha derivado en la redacción de un artículo científico y que pueden ser consultados de manera individualizada en los capítulos II, III y IV. En el capítulo II se evaluó la influencia de un total de 24 variables ambientales a nivel de paisaje y a nivel de árbol, muchas de ellas consecuencia del manejo tradicional del bosque en el oeste ibérico por parte del hombre, analizando la riqueza observada de especies y empleando los estimadores de diversidad verdadera. El estudio permitió demostrar que, son muchas las variables que deben ser tenidas en cuenta a la hora de aplic

Tree hollows are complex microhabitats in which a variety of abiotic and biotic factors shape the community assembly of saproxylic insects. Detecting non-random species co-occurrence patterns is a fundamental goal in ecology in order to understand the assembly mechanisms of communities. We study association patterns of species of Coleoptera and Diptera (Syrphidae), belonging to different trophic guilds, on 72 tree hollows at a local and regional scale in three protected areas in Mediterranean forests using a fixed–fixed null model. Our matrix-level analysis shows a tendency for segregation in species association (species exclusion) at the regional and site levels. However, the high complexity of tree-hollow habitats, offering different resources for a more or less specialized fauna, makes it difficult to prove competition interactions. Indeed, pairwise analysis shows a dominance of non-random aggregation patterns (species coexistence) at the local and regional levels. Both aggregation and segregation of non-random patterns were more common among species from different trophic guilds than within the same guilds, with predators being a common denominator for a high percentage of the inter-guild pairs. Our results suggest that predation and facilitation interactions, together with habitat segregation, are the main factors shaping tree-hollow assemblages, while competition seems to be less important. We conclude that species interactions take an important part of the process of assemblage structuration and special attention should be paid to ‘ecosystem engineers’ and threatened species in the conservation of tree hollow assemblages.

Las mariposas diurnas, están presentes en todo el mundo y tienen unos requerimientos biológicos que son bien conocidos, por lo que el estudio de sus comunidades nos aporta valiosa información sobre el estado de conservación de los ecosistemas y de los procesos de alteración ambiental. En este estudio se dan a conocer las especies que se encuentran en la Estación Biológica de Torretes, situado en Ibi (Alicante), en la ladera sur del Parque Natural de la Font Roja. Se trata de un espacio municipal de 53 ha cedido en custodia de territorio por el ayuntamiento de Ibi al Centro Iberoamericano de la Biodiversidad (CIBIO) de la Universidad de Alicante. Se han encontrado un total de 32 especies que viven en este espacio natural, lo que supone el 44% de las especies registradas en el Parque Natural de la Font Roja (Alicante) cuya extensión es de 2.298 ha. Este dato, y la abundancia de las especies registradas, indican la importancia que este espacio tiene como área de conservación entomológica., The diurnal butterflies, are present all over the world and have biological requirements that are well known, so the study of their communities provide us valuable information on the state of conservation of the ecosystems and the processes of environmental alteration. In this study, species which are found in the Biological Station of Torretes, where is placed in Ibi (Alicante), in the southern hillside of the Natural Park of Font Roja, are made known. It’s a municipal area of 53 ha, ceded in custody of territory by the town hall of Ibi to the Ibero-American Center of Biodiversity (CIBIO) of the University of Alicante. A total of 32 species that lives in this natural area had been found, which suppose the 44% of the species registered in the Natural Park of Font Roja (Alicante) whose extent is 2.298 ha. This data and the abundancy of the registered species, show the importance of this space as a entomological conservation area.

El estudio de la fauna de coleópteros saproxílicos en siete espacios protegidos de la península ibérica, ha permitido obtener datos sobre la abundancia y fenología del coleóptero xilomicetófago Platypus cylindrus, especie considerada plaga en numerosos países de la cuenca mediterránea. De todas las especies arbóreas muestreadas, su mayor abundancia ha sido detectada en los bosques de Quercus suber del Parque Natural de la Sierra de Espadán, particularmente en la localidad más antropizada y con actual manejo del corcho. En el resto de los espacios protegidos y especies arbóreas su presencia ha sido moderada. En el Parque Natural de la Sierra de Espadán P. cylindrus está activo durante un amplio rango de meses, con mayores abundancias entre agosto y septiembre, coincidiendo con lo observado en otras poblaciones de climas cálidos., During the last years, sampling of the saproxylic coleopteran communities in seven protected areas in the Iberian Peninsula, has allowed to obtain data of the abundance and phenology of the xylomycetophagous Platypus cylindrus, which is considered plague in some countries of Mediterranean basin. Between all the arboreal species sampled, the largest presence of P. cylindrus has been detected in the Quercus suber forests of the Natural Park of Sierra Espadán, particularly in the most anthropized and with cork management locality. In the rest of the protected areas and arboreal species sampled its presence has been moderate. In the Natural Park of Sierra Espadán, P. cylindrus has been active during a wide range of months, with the biggest abundances between August and September, similarly to other populations of warm climates.

Los insectos saproxílicos, que dependen de la presencia de madera muerta y/o en descomposición, de hongos de la madera, o bien de la presencia de otros organismos saproxílicos, en algún momento de su ciclo vital, desempeñan una función clave para el correcto funcionamiento de los ecosistemas de bosque, actuando como recicladores de los nutrientes contenidos en la madera en descomposición. La diversidad de insectos saproxílicos, y más concretamente de coleópteros, así como la estructura de los ensambles que conforman, se encuentran condicionadas por una serie de variables de carácter físico, químico y biótico. Comprender cómo este amplio conjunto de variables afecta a los patrones espacio-temporales de las comunidades, resulta esencial a la hora de elaborar estrategias de manejo de los ecosistemas, que permitan preservar este tipo de fauna, en muchas ocasiones, amenazada. Con este marco de fondo, el objetivo general de esta tesis doctoral reside en analizar el conjunto de factores ambientales que afectan a la diversidad y a la distribución espacio-temporal de los ensambles de coleópteros saproxílicos que habitan los bosques mediterráneos de roble melojo ubicados en el oeste de la península ibérica para, de este modo, poder proponer una serie de directrices a seguir, a la hora de manejar este tipo de ecosistemas. Este objetivo general se divide en una serie de objetivos específicos, cada uno de los cuales ha derivado en la redacción de un artículo científico y que pueden ser consultados de manera individualizada en los capítulos II, III y IV. En el capítulo II se evaluó la influencia de un total de 24 variables ambientales a nivel de paisaje y a nivel de árbol, muchas de ellas consecuencia del manejo tradicional del bosque en el oeste ibérico por parte del hombre, analizando la riqueza observada de especies y empleando los estimadores de diversidad verdadera. El estudio permitió demostrar que, son muchas las variables que deben ser tenidas en cuenta a la hora de aplic

Las mariposas diurnas, están presentes en todo el mundo y tienen unos requerimientos biológicos que son bien conocidos, por lo que el estudio de sus comunidades nos aporta valiosa información sobre el estado de conservación de los ecosistemas y de los procesos de alteración ambiental. En este estudio se dan a conocer las especies que se encuentran en la Estación Biológica de Torretes, situado en Ibi (Alicante), en la ladera sur del Parque Natural de la Font Roja. Se trata de un espacio municipal de 53 ha cedido en custodia de territorio por el ayuntamiento de Ibi al Centro Iberoamericano de la Biodiversidad (CIBIO) de la Universidad de Alicante. Se han encontrado un total de 32 especies que viven en este espacio natural, lo que supone el 44% de las especies registradas en el Parque Natural de la Font Roja (Alicante) cuya extensión es de 2.298 ha. Este dato, y la abundancia de las especies registradas, indican la importancia que este espacio tiene como área de conservación entomológica., The diurnal butterflies, are present all over the world and have biological requirements that are well known, so the study of their communities provide us valuable information on the state of conservation of the ecosystems and the processes of environmental alteration. In this study, species which are found in the Biological Station of Torretes, where is placed in Ibi (Alicante), in the southern hillside of the Natural Park of Font Roja, are made known. It’s a municipal area of 53 ha, ceded in custody of territory by the town hall of Ibi to the Ibero-American Center of Biodiversity (CIBIO) of the University of Alicante. A total of 32 species that lives in this natural area had been found, which suppose the 44% of the species registered in the Natural Park of Font Roja (Alicante) whose extent is 2.298 ha. This data and the abundancy of the registered species, show the importance of this space as a entomological conservation area.

Tree hollows are complex microhabitats in which a variety of abiotic and biotic factors shape the community assembly of saproxylic insects. Detecting non-random species co-occurrence patterns is a fundamental goal in ecology in order to understand the assembly mechanisms of communities. We study association patterns of species of Coleoptera and Diptera (Syrphidae), belonging to different trophic guilds, on 72 tree hollows at a local and regional scale in three protected areas in Mediterranean forests using a fixed–fixed null model. Our matrix-level analysis shows a tendency for segregation in species association (species exclusion) at the regional and site levels. However, the high complexity of tree-hollow habitats, offering different resources for a more or less specialized fauna, makes it difficult to prove competition interactions. Indeed, pairwise analysis shows a dominance of non-random aggregation patterns (species coexistence) at the local and regional levels. Both aggregation and segregation of non-random patterns were more common among species from different trophic guilds than within the same guilds, with predators being a common denominator for a high percentage of the inter-guild pairs. Our results suggest that predation and facilitation interactions, together with habitat segregation, are the main factors shaping tree-hollow assemblages, while competition seems to be less important. We conclude that species interactions take an important part of the process of assemblage structuration and special attention should be paid to ‘ecosystem engineers’ and threatened species in the conservation of tree hollow assemblages.

En la presente tesis doctoral se presenta un estudio profundo de los ensambles formados por insectos saproxílicos (Coleópteros y Dípteros Syrphidae) ligados a las cavidades arbóreas de quercínas ibéricas (Quercus spp). Las especies saproxílicas (coleópteros y dípteros sírfidos) conforman complejas redes ecológicas conectadas a través de diferentes interacciones de especies insecto-insecto. Nuestros hallazgos recalcan la importancia para la conservación de la comunidad entomológica saproxílica, centrar la atención en el estudio de especies clave que cumplen un papel fundamental en la organización de los ensambles al condicionar la presencia o la ausencia de otras especies o gremios de especies que se desarrollan dentro de cada oquedad (ej. especies “ingenieros del ecosistema”). Ponemos de manifiesto también la importancia que tiene la microbiota dentro la oquedad como recurso trófico de las fases larvarias acuáticas de especies de sírfidos que como adultos, son visitantes florales asiduos de las flores de nuestros bosques mediterráneos.

En la presente tesis doctoral se presenta un estudio profundo de los ensambles formados por insectos saproxílicos (Coleópteros y Dípteros Syrphidae) ligados a las cavidades arbóreas de quercínas ibéricas (Quercus spp). Las especies saproxílicas (coleópteros y dípteros sírfidos) conforman complejas redes ecológicas conectadas a través de diferentes interacciones de especies insecto-insecto. Nuestros hallazgos recalcan la importancia para la conservación de la comunidad entomológica saproxílica, centrar la atención en el estudio de especies clave que cumplen un papel fundamental en la organización de los ensambles al condicionar la presencia o la ausencia de otras especies o gremios de especies que se desarrollan dentro de cada oquedad (ej. especies “ingenieros del ecosistema”). Ponemos de manifiesto también la importancia que tiene la microbiota dentro la oquedad como recurso trófico de las fases larvarias acuáticas de especies de sírfidos que como adultos, son visitantes florales asiduos de las flores de nuestros bosques mediterráneos.

Volatile organic compounds (VOCs) emitted by plants play a critical role in the structure of the faunal communities that are associated with them. The aim of this work was to provide a detailed list of VOCs emitted by the oak species Quercus pyrenaica Willd. and to analyse the spatio-temporal variation in the emission rates of these compounds and in the diversity of saproxylic beetle assemblages associated with this tree species. VOCs sample collection was carried out by a dynamic flow-through enclosure technique with subsequent analysis by gas chromatography–mass spectrometry. Statistical differences in the emission rates of VOCs and in the diversity of saproxylic beetles were found between seasons. Temperature and relative humidity seemed to be related to these variations. Spatially, neither qualitative nor quantitative statistical differences in the emission of VOCs were found. Nevertheless, the results demonstrated a trend such that larger trees emitted VOCs with higher intensity and hosted a greater diversity of saproxylic beetles. Our hypothesis that beetles responded to certain blends of VOCs emitted at different rates by potential host tress and not so much to the absence or presence of a particular compound was reinforced by the absence of qualitative differences in the VOCs emitted by trees of different sizes. These results open a new field of study, and it will be necessary to become more involved with the subject to evaluate the real influence of these VOCs released by trees in saproxylic beetle assemblages.

Saproxylic insect communities inhabiting tree hollows in Mediterranean forests depend on a combination of physical characteristics and interactions occurring between community member species. Despite the need to preserve these organisms, little is known about their interrelationships, in particular those relationships between saproxylic insects and microbiota occurring in these microhabitats. In tree hollows of Quercus rotundifolia Lamark that hold water and contain dead leaves, abundant microbial populations can be found. Developing on them are the larvae of Mallota dusmeti Andréu, 1926 (Diptera: Syrphidae), a vulnerable species (IUCN category: Marcos-García and Quinto 2011). This study provides the first data on the microbiota living inside the gut of the larvae of M. dusmeti, as well as the microbiota in the hollow where these larvae develop. Bacteria were identified by amplification and partial sequencing of the V1–V3 regions and the complete nucleotide sequence of 16S rRNA genes. We found eight species of bacteria living in tree hollows and three species in the gut of M. dusmeti larvae: Bacillus cereus, Bacillus toyonensis, and Lysinibacillus sphaericus. The filter-feeding mechanism characteristic of M. dusmeti larvae is selective in enabling ingestion of bacteria only above 2.1 µm in diameter.

Mediterranean oak forests of the Iberian Peninsula host a great diversity of saproxylic beetles. For centuries, humans have carried out traditional management practices in this area, at both habitat and tree level, causing changes in forest structure. The aim of this study was to evaluate the anthropic effect of these traditional practices on saproxylic beetle diversity by measuring a set of environmental variables related to forest structure at both plot and tree level. Fauna was collected using window traps over a period of 12 mo. Multiple regression procedures showed which variables significantly affected the diversity of the studied assemblage. Our results demonstrated that the different metrics used to assess the diversity of assemblages responded variably depending on the management strategies applied and the level at which they were carried out. Certain management practices that disrupted the landscape from its natural state, such as the introduction of livestock or the local removal of particular trees, maximized species richness but, nevertheless, had a negative effect on the rest of diversity metrics analyzed. However, other practices such as pollarding, which involves the suppression of the main branch of the tree, had a positive effect on all diversity metrics evaluated as it promoted the formation of potential microhabitats for saproxylic fauna. We concluded that not all types and degrees of traditional forest management favor saproxylic beetle diversity and that different diversity metrics should be taken into consideration in future strategies for the protection and conservation of this fauna.

Los odonatos son indicadores biológicos de la calidad de los medios acuáticos, ya que requieren, en la mayoría de los casos, aguas limpias y bien oxigenadas para desarrollar sus etapas larvarias. Muchas especies han sido incluidas en la Lista Roja de especies amenazadas. Se ha llevado a cabo un estudio de la fauna de Odonatos en la Estación Biológica Torretes - Jardín Botánico de la Universidad de Alicante (Ibi, Alicante), un espacio de bosque mediterráneo de 53 hectáreas, que está gestionado por el Instituto de Investigación CIBIO de la Universidad de Alicante. Este centro está destinado a investigar y difundir el valor de la biodiversidad y la conservación. Se han estudiado diversos puntos de agua permanentes con el objetivo de determinar áreas de conservación de la biodiversidad. En la estación biológica se registraron 16 especies de odonatos de los 28 citadas en ambientes naturales para la provincia de Alicante, lo que resaltan la importancia de este espacio natural en la conservación de estos insectos., Odonates are biological indicators of the aquatic environments quality, because them require, in most cases, clean and well oxygenated waters to develop their larval stages. Many species have been included in the Red List of threatened species for their vulnerability to contaminated environments. A study of odonata fauna was carried out in several permanent water points in the Biological Station – Botanical Garden of Torretes (Ibi, Alicante), a Mediterranean forest space of 53 hectares, managed by the Research Institute CIBIO of the University of Alicante. This center aims to investigate and disseminate the value of biodiversity and conservation. In the biological station was collected 16 species Odonates of the 28 reported in natural environments for the Alicante province, which highlight the importance of this natural space in the conservation and biodiversity of these insects.

The temporal factor has been widely neglected in studies related to species distribution. However, knowing the species phenology throughout the year could be a key element in ecological studies, more so considering the current climate change framework. The intra-annual temporal patterns of the saproxylic beetle assemblage inhabiting the oak forests in the western Iberian Peninsula were evaluated in terms of species richness and composition. Moreover, we analysed the temporal patterns of species richness and body size, with respect to the abiotic factors of temperature and relative humidity. The marked seasonality of the Mediterranean weather governed, to a great extent, the temporal patterns of the assemblage, as both species richness and body size showed a positive correlation with temperature and a negative correlation with relative humidity. The high temperatures reached in August limited the activity of certain species, causing a marked decrease in species richness. The results revealed that species body size decreased in the colder months of the year and vice versa, which could fit with the inverse of Bergmann’s rule; nevertheless, studies are needed to address the contribution of species physiology and autoecology to the observed temporal patterns. Regarding species composition, the partition of beta diversity in its two components showed a constant process of species turnover throughout the year. We conclude that, due to global warming, the study of temporal patterns of assemblages is becoming all the more important, since it could significantly affect the spatio-temporal distribution of species and the interactions between them.

Chemical changes to Quercus wood caused by the larvae of the saproxylic beetle Cetonia aurataeformis have been evaluated using elemental analysis, thermal analysis, infrared spectroscopy and nuclear magnetic resonance. Faeces of C. aurataeformis from Quercus rotundifolia tree hollows and faeces of larval C. aurataeformis reared under laboratory conditions were collected and analysed. The results suggest that larval C. aurataeformis are able to decompose the polysaccharides in Q. rotundifolia wood, producing a residue with higher concentration of N and P, and organic structures with different stability than those found in wood. The higher N and P concentrations and the reduction of the particle size would facilitate the activity of decomposing microorganisms on C. aurataeformis faeces. The comparison of the faeces from tree hollows with those from the larvae reared in the laboratory revealed that both N and P concentrations and the stability of organic structures in the region of lignin increased with the amount of time that faeces were in Q. rotundifolia hollows, while the stability of the organic structures in the polysaccharides region decreased. The lower stability of organic compounds in faeces gives rise to an increase of soluble organic matter with higher N concentration than that solubilised from the wood the beetles feed on. Moreover, faeces collected in Q. rotundifolia hollows showed the highest values of humification and aromaticity, determined by the spectroscopic indices of soluble organic matter, highlighting the action of this cetonid in the carbon and nitrogen cycle in saproxylic environments.

Canthon cyanellus is a roller dung beetle with a wide distribution range in the tropical forests of the New World. In Mexico, it inhabits the Pacific and the Gulf coasts, the Yucatan Peninsula and the south mainly in the State of Chiapas. This species shows a wide geographical variation in cuticle color, which has been used as defining trait for subspecies. In this study we analyzed the phylogeographic and demographic history of the Mexican populations of C. cyanellus using DNA sequences of the nuclear ITS2, and the mitochondrial COI and 16S genes. We found that not all the current valid subspecies are supported by the molecular analysis. The populations are genetically and geographically structured in five lineages. The diversification events that gave origin to the main lineages within this species complex occurred during the Pleistocine in a time range of 1.63–0.91 Myr. The demographic history of these lineages suggests post-glacial expansions toward the middle and the end of the Pleistocene. The combined data of mitochondrial and nuclear DNA suggest that the phylogeographic structure and demographic history of the C. cyanellus populations are the result of: the geological and volcanic activity that occurred from the end of the Pliocene to the Pleistocene; and the contraction and expansion of tropical forests due to the glacial and inter-glacial cycles during the Pleistocene. Landscape changes derived from historical events have affected the demographic history of the populations of this species. The results presented here point to the need to review the taxonomic status and delimitation of the lineages encompassed in the Canthon cyanellus complex.

En la presente tesis doctoral se presenta un estudio profundo de los ensambles formados por insectos saproxílicos (Coleópteros y Dípteros Syrphidae) ligados a las cavidades arbóreas de quercínas ibéricas (Quercus spp). Las especies saproxílicas (coleópteros y dípteros sírfidos) conforman complejas redes ecológicas conectadas a través de diferentes interacciones de especies insecto-insecto. Nuestros hallazgos recalcan la importancia para la conservación de la comunidad entomológica saproxílica, centrar la atención en el estudio de especies clave que cumplen un papel fundamental en la organización de los ensambles al condicionar la presencia o la ausencia de otras especies o gremios de especies que se desarrollan dentro de cada oquedad (ej. especies “ingenieros del ecosistema”). Ponemos de manifiesto también la importancia que tiene la microbiota dentro la oquedad como recurso trófico de las fases larvarias acuáticas de especies de sírfidos que como adultos, son visitantes florales asiduos de las flores de nuestros bosques mediterráneos.

Mediterranean oak forests of the Iberian Peninsula host a great diversity of saproxylic beetles. For centuries, humans have carried out traditional management practices in this area, at both habitat and tree level, causing changes in forest structure. The aim of this study was to evaluate the anthropic effect of these traditional practices on saproxylic beetle diversity by measuring a set of environmental variables related to forest structure at both plot and tree level. Fauna was collected using window traps over a period of 12 mo. Multiple regression procedures showed which variables significantly affected the diversity of the studied assemblage. Our results demonstrated that the different metrics used to assess the diversity of assemblages responded variably depending on the management strategies applied and the level at which they were carried out. Certain management practices that disrupted the landscape from its natural state, such as the introduction of livestock or the local removal of particular trees, maximized species richness but, nevertheless, had a negative effect on the rest of diversity metrics analyzed. However, other practices such as pollarding, which involves the suppression of the main branch of the tree, had a positive effect on all diversity metrics evaluated as it promoted the formation of potential microhabitats for saproxylic fauna. We concluded that not all types and degrees of traditional forest management favor saproxylic beetle diversity and that different diversity metrics should be taken into consideration in future strategies for the protection and conservation of this fauna.

Los odonatos son indicadores biológicos de la calidad de los medios acuáticos, ya que requieren, en la mayoría de los casos, aguas limpias y bien oxigenadas para desarrollar sus etapas larvarias. Muchas especies han sido incluidas en la Lista Roja de especies amenazadas. Se ha llevado a cabo un estudio de la fauna de Odonatos en la Estación Biológica Torretes - Jardín Botánico de la Universidad de Alicante (Ibi, Alicante), un espacio de bosque mediterráneo de 53 hectáreas, que está gestionado por el Instituto de Investigación CIBIO de la Universidad de Alicante. Este centro está destinado a investigar y difundir el valor de la biodiversidad y la conservación. Se han estudiado diversos puntos de agua permanentes con el objetivo de determinar áreas de conservación de la biodiversidad. En la estación biológica se registraron 16 especies de odonatos de los 28 citadas en ambientes naturales para la provincia de Alicante, lo que resaltan la importancia de este espacio natural en la conservación de estos insectos., Odonates are biological indicators of the aquatic environments quality, because them require, in most cases, clean and well oxygenated waters to develop their larval stages. Many species have been included in the Red List of threatened species for their vulnerability to contaminated environments. A study of odonata fauna was carried out in several permanent water points in the Biological Station – Botanical Garden of Torretes (Ibi, Alicante), a Mediterranean forest space of 53 hectares, managed by the Research Institute CIBIO of the University of Alicante. This center aims to investigate and disseminate the value of biodiversity and conservation. In the biological station was collected 16 species Odonates of the 28 reported in natural environments for the Alicante province, which highlight the importance of this natural space in the conservation and biodiversity of these insects.

The temporal factor has been widely neglected in studies related to species distribution. However, knowing the species phenology throughout the year could be a key element in ecological studies, more so considering the current climate change framework. The intra-annual temporal patterns of the saproxylic beetle assemblage inhabiting the oak forests in the western Iberian Peninsula were evaluated in terms of species richness and composition. Moreover, we analysed the temporal patterns of species richness and body size, with respect to the abiotic factors of temperature and relative humidity. The marked seasonality of the Mediterranean weather governed, to a great extent, the temporal patterns of the assemblage, as both species richness and body size showed a positive correlation with temperature and a negative correlation with relative humidity. The high temperatures reached in August limited the activity of certain species, causing a marked decrease in species richness. The results revealed that species body size decreased in the colder months of the year and vice versa, which could fit with the inverse of Bergmann’s rule; nevertheless, studies are needed to address the contribution of species physiology and autoecology to the observed temporal patterns. Regarding species composition, the partition of beta diversity in its two components showed a constant process of species turnover throughout the year. We conclude that, due to global warming, the study of temporal patterns of assemblages is becoming all the more important, since it could significantly affect the spatio-temporal distribution of species and the interactions between them.

Volatile organic compounds (VOCs) emitted by plants play a critical role in the structure of the faunal communities that are associated with them. The aim of this work was to provide a detailed list of VOCs emitted by the oak species Quercus pyrenaica Willd. and to analyse the spatio-temporal variation in the emission rates of these compounds and in the diversity of saproxylic beetle assemblages associated with this tree species. VOCs sample collection was carried out by a dynamic flow-through enclosure technique with subsequent analysis by gas chromatography–mass spectrometry. Statistical differences in the emission rates of VOCs and in the diversity of saproxylic beetles were found between seasons. Temperature and relative humidity seemed to be related to these variations. Spatially, neither qualitative nor quantitative statistical differences in the emission of VOCs were found. Nevertheless, the results demonstrated a trend such that larger trees emitted VOCs with higher intensity and hosted a greater diversity of saproxylic beetles. Our hypothesis that beetles responded to certain blends of VOCs emitted at different rates by potential host tress and not so much to the absence or presence of a particular compound was reinforced by the absence of qualitative differences in the VOCs emitted by trees of different sizes. These results open a new field of study, and it will be necessary to become more involved with the subject to evaluate the real influence of these VOCs released by trees in saproxylic beetle assemblages.

Saproxylic insect communities inhabiting tree hollows in Mediterranean forests depend on a combination of physical characteristics and interactions occurring between community member species. Despite the need to preserve these organisms, little is known about their interrelationships, in particular those relationships between saproxylic insects and microbiota occurring in these microhabitats. In tree hollows of Quercus rotundifolia Lamark that hold water and contain dead leaves, abundant microbial populations can be found. Developing on them are the larvae of Mallota dusmeti Andréu, 1926 (Diptera: Syrphidae), a vulnerable species (IUCN category: Marcos-García and Quinto 2011). This study provides the first data on the microbiota living inside the gut of the larvae of M. dusmeti, as well as the microbiota in the hollow where these larvae develop. Bacteria were identified by amplification and partial sequencing of the V1–V3 regions and the complete nucleotide sequence of 16S rRNA genes. We found eight species of bacteria living in tree hollows and three species in the gut of M. dusmeti larvae: Bacillus cereus, Bacillus toyonensis, and Lysinibacillus sphaericus. The filter-feeding mechanism characteristic of M. dusmeti larvae is selective in enabling ingestion of bacteria only above 2.1 µm in diameter.

Chemical changes to Quercus wood caused by the larvae of the saproxylic beetle Cetonia aurataeformis have been evaluated using elemental analysis, thermal analysis, infrared spectroscopy and nuclear magnetic resonance. Faeces of C. aurataeformis from Quercus rotundifolia tree hollows and faeces of larval C. aurataeformis reared under laboratory conditions were collected and analysed. The results suggest that larval C. aurataeformis are able to decompose the polysaccharides in Q. rotundifolia wood, producing a residue with higher concentration of N and P, and organic structures with different stability than those found in wood. The higher N and P concentrations and the reduction of the particle size would facilitate the activity of decomposing microorganisms on C. aurataeformis faeces. The comparison of the faeces from tree hollows with those from the larvae reared in the laboratory revealed that both N and P concentrations and the stability of organic structures in the region of lignin increased with the amount of time that faeces were in Q. rotundifolia hollows, while the stability of the organic structures in the polysaccharides region decreased. The lower stability of organic compounds in faeces gives rise to an increase of soluble organic matter with higher N concentration than that solubilised from the wood the beetles feed on. Moreover, faeces collected in Q. rotundifolia hollows showed the highest values of humification and aromaticity, determined by the spectroscopic indices of soluble organic matter, highlighting the action of this cetonid in the carbon and nitrogen cycle in saproxylic environments.

Canthon cyanellus is a roller dung beetle with a wide distribution range in the tropical forests of the New World. In Mexico, it inhabits the Pacific and the Gulf coasts, the Yucatan Peninsula and the south mainly in the State of Chiapas. This species shows a wide geographical variation in cuticle color, which has been used as defining trait for subspecies. In this study we analyzed the phylogeographic and demographic history of the Mexican populations of C. cyanellus using DNA sequences of the nuclear ITS2, and the mitochondrial COI and 16S genes. We found that not all the current valid subspecies are supported by the molecular analysis. The populations are genetically and geographically structured in five lineages. The diversification events that gave origin to the main lineages within this species complex occurred during the Pleistocine in a time range of 1.63–0.91 Myr. The demographic history of these lineages suggests post-glacial expansions toward the middle and the end of the Pleistocene. The combined data of mitochondrial and nuclear DNA suggest that the phylogeographic structure and demographic history of the C. cyanellus populations are the result of: the geological and volcanic activity that occurred from the end of the Pliocene to the Pleistocene; and the contraction and expansion of tropical forests due to the glacial and inter-glacial cycles during the Pleistocene. Landscape changes derived from historical events have affected the demographic history of the populations of this species. The results presented here point to the need to review the taxonomic status and delimitation of the lineages encompassed in the Canthon cyanellus complex.

Los árboles han jugado un papel fundamental en el desarrollo de las civilizaciones, tanto como recursos de aprovisionamiento como por otros servicios ecosistémicos. Sin embargo hay una fuerte perturbación de los bosques tropicales que ha disminuido la cantidad y diversidad de los árboles. Una de las causas principales de esta situación es el cambio de uso del suelo, sobre todo para actividades ganaderas, que en el estado de Veracruz, México, ocupan alrededor de 3.7 millones de hectáreas (50.6% de su territorio). El objetivo de este trabajo fue investigar el conocimiento que los ganaderos tienen sobre las especies arbóreas, sus usos, su importancia cultural y los cambios que han sucedido a lo largo del tiempo. Se mencionaron 68 especies de árboles y se hizo una clasificación de 22 tipos de usos. Se calculó el índice de importancia cultural de cada especie y se describieron los cambios más importantes en el estilo de vida de las comunidades de estudio. Se encontró que hay un conocimiento amplio sobre los árboles pero se está perdiendo rápidamente. Los árboles se usan no solo para obtener beneficios en la ganadería sino para satisfacer otras necesidades de la vida cotidiana. La cantidad y la diversidad de especies arbóreas refleja el estilo de vida de las comunidades junto con sus influencias y cambios en el tiempo. Las decisiones de los ganaderos configuran el paisaje y por lo tanto se recomienda aumentar la cantidad de árboles en los potreros, su conservación y su uso para mantener los servicios ecosistémicos que proveen., Trees have played an important role in the development of civilizations, both for provisioning of resources and for other environmental services. However, there is a strong decrease in the quantity and diversity of tropical forests trees due to land use changes. One of the main causes of this situation is the livestock activity, which in the state of Veracruz, Mexico, occupies a surface of about 3.7 million hectares (representing 50.6% of its territory). The objective of this study was to research into cattle ranchers’ knowledge of arboreal species, their uses, their cultural importance and the changes that have taken place over time. Sixty eight species of trees were mentioned and their uses were classified in 22 types of uses. The cultural importance index was calculated for each species and the most important changes in the communities’ lifestyle were described. The results showed that ranchers have a wide knowledge about trees but it is rapidly disappearing. Trees are used not only to get benefits for the livestock activity but also to satisfy other needs of daily life. The quantity and diversity of arboreal species reflect the lifestyle, influences and changes over time within the communities. The decisions of ranchers configure the landscape, and therefore the recommendation is to increase the amount of trees, their conservation and uses to maintain the environmental services they provide.