Con este trabajo se pretende identificar las áreas prioritarias de conservación en la Cuenca del ... more Con este trabajo se pretende identificar las áreas prioritarias de conservación en la Cuenca del Río Segura, utilizando los coleópteros acuáticos como herramienta. Se ha empleado el índice denominado Interés de Conservación (IC) (Millán 1991), que atiende a criterios de riqueza y rareza de especies, y es una modificación del índice Rarity Quality Factor (Eyre & Rushton, 1989). Este índice se ha aplicado a la comunidad de Adephaga acuáticos y al total de coleópteros acuáticos, tanto por estaciones (248 y 377) como por cuadrículas UTM de 10 x 10 Km. (116 cuadrículas, aproximadamente el 50% de la superficie total). En función de los valores del IC se han clasificado las estaciones y cuadrículas según su interés de conservación y se han identificado las áreas prioritarias de conservación para la Cuenca del Río Segura. Por último, se ha elaborado una cartografía superponiendo las áreas prioritarias y los Espacios Naturales Protegidos, para determinar el grado de solapamiento existente y detectar vacíos en conservación. Los resultados más destacables son: 1.-Se ha registrado un total de 230 especies de coleópteros acuáticos, aproximadamente el 36 % de la riqueza de la Península Ibérica, de las cuales 32 son endemismos ibéricos, 4 de ellos exclusivos para la Cuenca del Río Segura (Hydraena mecai, H. mandfredjaechi, Limnebius millani y Ochthebius albacetinus). 2.-Dos estaciones, Nacimiento del Río Madera y Chorros del Río Mundo, aparecen siempre dentro de las 10 más valoradas, por lo que merecen una especial atención cara a su conservación. 3. Los Adephaga acuáticos pueden reflejar condiciones ambientales similares al conjunto de los coleópteros acuáticos, constituyendo un buen indicador de biodiversidad. 4. La mayoría de las áreas con interés de conservación máximo se localizan en tramos de cabecera, en el noroeste de la cuenca, con predominio de hábitats tipo como arroyos de montaña. 5. La coincidencia entre las áreas prioritarias de conservación y los ENPs ("Espacios Naturales Protegidos") es de aproximadamente el 67 %, por lo tanto, existe un vacío que representa el 33 % de la superficie considerada como de interés de conservación máximo.
Con este trabajo se pretende identificar las áreas prioritarias de conservación en la Cuenca del ... more Con este trabajo se pretende identificar las áreas prioritarias de conservación en la Cuenca del Río Segura, utilizando los coleópteros acuáticos como herramienta. Se ha empleado el índice denominado Interés de Conservación (IC) (Millán 1991), que atiende a criterios de riqueza y rareza de especies, y es una modificación del índice Rarity Quality Factor (Eyre & Rushton, 1989). Este índice se ha aplicado a la comunidad de Adephaga acuáticos y al total de coleópteros acuáticos, tanto por estaciones (248 y 377) como por cuadrículas UTM de 10 x 10 Km. (116 cuadrículas, aproximadamente el 50% de la superficie total). En función de los valores del IC se han clasificado las estaciones y cuadrículas según su interés de conservación y se han identificado las áreas prioritarias de conservación para la Cuenca del Río Segura. Por último, se ha elaborado una cartografía superponiendo las áreas prioritarias y los Espacios Naturales Protegidos, para determinar el grado de solapamiento existente y detectar vacíos en conservación. Los resultados más destacables son: 1.-Se ha registrado un total de 230 especies de coleópteros acuáticos, aproximadamente el 36 % de la riqueza de la Península Ibérica, de las cuales 32 son endemismos ibéricos, 4 de ellos exclusivos para la Cuenca del Río Segura (Hydraena mecai, H. mandfredjaechi, Limnebius millani y Ochthebius albacetinus). 2.-Dos estaciones, Nacimiento del Río Madera y Chorros del Río Mundo, aparecen siempre dentro de las 10 más valoradas, por lo que merecen una especial atención cara a su conservación. 3. Los Adephaga acuáticos pueden reflejar condiciones ambientales similares al conjunto de los coleópteros acuáticos, constituyendo un buen indicador de biodiversidad. 4. La mayoría de las áreas con interés de conservación máximo se localizan en tramos de cabecera, en el noroeste de la cuenca, con predominio de hábitats tipo como arroyos de montaña. 5. La coincidencia entre las áreas prioritarias de conservación y los ENPs ("Espacios Naturales Protegidos") es de aproximadamente el 67 %, por lo tanto, existe un vacío que representa el 33 % de la superficie considerada como de interés de conservación máximo.
New faunistic and distributional data on aquatic Hemiptera from the Oriental Region of Morocco an... more New faunistic and distributional data on aquatic Hemiptera from the Oriental Region of Morocco and the Moulouya River basin, covering an area of 119,268 km2, are presented. An annotated list of 45 species, 21 genera and 11 families is provided. Nine species are new records for the entire studied area, and two for the Moulouya River basin. We rediscovered Velia noualhieri iberica and Notonecta viridis after eight decades. We also provide novel records for Aphelocheirus pemae and Hebrus atlas, which were recently described from Morocco, and for the invasive corixid Trichocorixa verticalis verticalis. The dominance of species with broad distributions points to the high dispersal dynamics of the Hemiptera community in the study area, similar to that of other areas where a semiarid climate prevails.
This study updates current knowledge of the relationships and geographical distributions of the s... more This study updates current knowledge of the relationships and geographical distributions of the species from the genus Aphelocheirus in the Iberian Peninsula which, until now, have been involved in nomenclatural and taxonomic confusion. The morphological and molecular analyses presented in this study confirm the taxonomic validity of A. murcius and the absence of A. aestivalis in the Iberian Peninsula. The shape of the left paramere emerged as the only valid characteristic to differentiate both species. Specimens of Aphelocheirus from northern Spain, previously identified as A. murcius, formed an independent lineage genetically distinct to A. murcius and A. aestivalis, although morphologically indistinguishable from A. murcius.
Protected area networks represent one of the mainstays of global conservation polices and are 35 ... more Protected area networks represent one of the mainstays of global conservation polices and are 35 therefore central to current efforts to maintain biodiversity. However, a major limitation of most 36 conservation strategies is their bias towards particular taxonomic groups and ecosystems, 37 meaning that many taxa and habitats are often only incidentally protected as a by-product of 38 inclusion within reserves. Here we investigate how effectively protected area networks, not 39 specifically designated for freshwaters, support aquatic biodiversity in the Iberian Peninsula 40 (Spain and Portugal), using data for water beetles, surrogates of overall macroinvertebrate 41 diversity in these habitats. We explore the behaviour of different measures (alpha, beta and 42 gamma) of both taxonomic and functional diversity at different spatial scales. Overall our 43 findings highlight the contrasting performance of reserve systems in the maintenance of either 44 taxonomic or functional diversity, as well as the importance of spatial scale. Iberian reserves 45 perform relatively well in supporting taxonomic diversity of water beetles at the peninsular 46 scale, but the same protected areas poorly represent functional diversity. Such a mismatch 47 cautions against the use of any one diversity component as a surrogate for others, and 48 emphasizes the importance of adopting an integrative approach to biodiversity conservation in 49 aquatic ecosystems. Furthermore, our results often show contrasting patterns at smaller spatial 50 scales, highlighting the need to consider the influence of scale when evaluating the effectiveness 51 of protected area networks.
Transitions from fresh to saline habitats are restricted to a handful of insect lineages, since t... more Transitions from fresh to saline habitats are restricted to a handful of insect lineages, since the colonization of saline waters requires specialized mechanisms to deal with osmotic stress. Previous studies have suggested that tolerance to salinity and desiccation could be mechanistically and evolutionarily linked, but the temporal sequence of these adaptations is not well established for individual lineages. We combined molecular, physiological and ecological data to explore the evolution of desiccation resistance, hyporegulation ability (i.e. the ability to osmoregulate in hyperosmotic media) and habitat transitions in the water beetle genus Enochrus subgenus Lumetus (Hydrophilidae). We tested whether enhanced desiccation resistance evolved before increases in hyporegulation ability or vice versa, or whether the two mechanisms evolved in parallel. The most recent ancestor of Lumetus was inferred to have high desiccation resistance and moderate hyporegulation ability. There were repeated shifts between habitats with differing levels of salinity in the radiation of the group; those to the most saline habitats generally occurring more rapidly than those to less saline ones. Significant and accelerated changes in hyporegulation ability evolved in parallel with smaller and more progressive increases in desiccation resistance across the phylogeny, associated with the colonisation of meso-and hypersaline waters during global aridification events. All species with high hyporegulation ability were also desiccationresistant, but not vice versa. Overall, results are consistent with the hypothesis that desiccation resistance mechanisms evolved first and provided the physiological basis for the development of hyporegulation ability, allowing these insects to colonize and diversify across meso-and hypersaline habitats.
Hydrocarbons are the principal component of insect cuticle and play an important role in maintain... more Hydrocarbons are the principal component of insect cuticle and play an important role in maintaining water balance. Cuticular impermeability could be an adaptative response to salinity and desiccation in aquatic insects; however, cuticular hydrocarbons have been poorly explored in this group and there are no previous data on saline species. We characterized cuticular hydrocarbons of adults and larvae of two saline aquatic beetles, namely Nebrioporus baeticus (Dytiscidae) and Enochrus jesusarribasi (Hydrophilidae), using a gas chromatograph coupled to a mass spectrometer. The CHC profile of adults of both species, characterized by a high abundance of branched alkanes and low of unsaturated alkenes, seems to be more similar to that of some terrestrial beetles (e.g., desert Tenebrionidae) compared with other aquatic Coleoptera (freshwater Dytiscidae). Adults of E. jesusarribasi had longer chain compounds than N. baeticus, in agreement with their higher resistance to salinity and desicc...
Exposing organisms to a particular stressor may enhance tolerance to a subsequent stress, when pr... more Exposing organisms to a particular stressor may enhance tolerance to a subsequent stress, when protective mechanisms against the two stressors are shared. Such cross-tolerance is a common adaptive response in dynamic multivariate environments and often indicates potential co-evolution of stress traits. Many aquatic insects in inland saline waters from Mediterranean-climate regions are sequentially challenged with salinity and desiccation stress. Thus, cross-tolerance to these physiologically similar stressors could have been positively selected in insects of these regions. We used adults of the saline water beetles Enochrus jesusarribasi (Hydrophilidae) and Nebrioporus baeticus (Dytiscidae) to test cross-tolerance responses to desiccation and salinity. In independent laboratory experiments, we evaluated the effects of (i) salinity stress on the subsequent resistance to desiccation and (ii) desiccation stress (rapid and slow dehydration) on the subsequent tolerance to salinity. Survival, water loss and haemolymph osmolality were measured. Exposure to stressful salinity improved water control under subsequent desiccation stress in both species, with a clear cross-tolerance (enhanced performance) in N. baeticus. In contrast, general negative effects on performance were found under the inverse stress sequence. The rapid and slow dehydration produced different water loss and haemolymph osmolality dynamics that were reflected in different survival patterns. Our finding of cross-tolerance to salinity and desiccation in ecologically similar species from distant lineages, together with parallel responses between salinity and thermal stress previously found in several aquatic taxa, highlights the central role of adaption to salinity and co-occurring stressors in arid inland waters, having important implications for the species' persistence under climate change.
A new species of Aphelocheirus (Hemiptera: Heteroptera: Aphelocheiridae) inhabiting riffles of a ... more A new species of Aphelocheirus (Hemiptera: Heteroptera: Aphelocheiridae) inhabiting riffles of a stream in Kerala state in southern India is described. Aphelocheirus kaygieyess n. sp. is diagnosed by widely separated hemelytra and the pattern of dark maculation on the vertex. This species is compared to other Indian species of Aphelocheirus. Seven species of Aphelocheirus are known now from India.
BackgroundDesiccation resistance shapes the distribution of terrestrial insects at multiple spati... more BackgroundDesiccation resistance shapes the distribution of terrestrial insects at multiple spatial scales. However, responses to drying stress have been poorly studied in aquatic groups, despite their potential role in constraining their distribution and diversification, particularly in arid and semi-arid regions.MethodsWe examined desiccation resistance in adults of four congeneric water beetle species (Enochrus, family Hydrophilidae) with contrasting habitat specificity (lenticvs.lotic systems and different salinity optima from fresh- to hypersaline waters). We measured survival, recovery capacity and key traits related to desiccation resistance (fresh mass, % water content, % cuticle content and water loss rate) under controlled exposure to desiccation, and explored their variability within and between species.ResultsMeso- and hypersaline species were more resistant to desiccation than freshwater and hyposaline ones, showing significantly lower water loss rates and higher water ...
Predicting the richness of aquatic beetles and bugs in a semi-arid mediterranean region The south... more Predicting the richness of aquatic beetles and bugs in a semi-arid mediterranean region The southeastern Iberian Peninsula is a semi-arid region recognised as an area of high aquatic biodiversity. Water beetles (Coleoptera) and water bugs (Hemiptera) are two of the region's most thoroughly studied insect groups. An exhaustive database of aquatic beetles and bugs from the Region of Murcia (SE Spain) and a set of 33 variables were employed for two related purposes: a) to describe the sampling effort conducted in the study area on these groups in order to identify zones with reliable inventories and b) with this information as a base, to forecast the distribution of species richness for each group. Theoretical estimates were based on the Clench function applied to the accumulated number of samples and were constructed with general linear models (GLM). The following results were obtained: 1) the percentage of grid cells that can be considered to be well sampled in the study area (143 10 × 10 km UTM grid cells) is approximately 14 % for beetles and 22 % for bugs; 2) well-surveyed cells are evenly distributed according to the previously defined physioclimatic subareas, which enable the use of these grid cells for modelling the richness distribution; and 3) a more accurate picture of the actual richness patterns for both groups is shown by the analysis. These results were combined to identify key areas where future sampling efforts must be focused.
Con este trabajo se pretende identificar las áreas prioritarias de conservación en la Cuenca del ... more Con este trabajo se pretende identificar las áreas prioritarias de conservación en la Cuenca del Río Segura, utilizando los coleópteros acuáticos como herramienta. Se ha empleado el índice denominado Interés de Conservación (IC) (Millán 1991), que atiende a criterios de riqueza y rareza de especies, y es una modificación del índice Rarity Quality Factor (Eyre & Rushton, 1989). Este índice se ha aplicado a la comunidad de Adephaga acuáticos y al total de coleópteros acuáticos, tanto por estaciones (248 y 377) como por cuadrículas UTM de 10 x 10 Km. (116 cuadrículas, aproximadamente el 50% de la superficie total). En función de los valores del IC se han clasificado las estaciones y cuadrículas según su interés de conservación y se han identificado las áreas prioritarias de conservación para la Cuenca del Río Segura. Por último, se ha elaborado una cartografía superponiendo las áreas prioritarias y los Espacios Naturales Protegidos, para determinar el grado de solapamiento existente y detectar vacíos en conservación. Los resultados más destacables son: 1.-Se ha registrado un total de 230 especies de coleópteros acuáticos, aproximadamente el 36 % de la riqueza de la Península Ibérica, de las cuales 32 son endemismos ibéricos, 4 de ellos exclusivos para la Cuenca del Río Segura (Hydraena mecai, H. mandfredjaechi, Limnebius millani y Ochthebius albacetinus). 2.-Dos estaciones, Nacimiento del Río Madera y Chorros del Río Mundo, aparecen siempre dentro de las 10 más valoradas, por lo que merecen una especial atención cara a su conservación. 3. Los Adephaga acuáticos pueden reflejar condiciones ambientales similares al conjunto de los coleópteros acuáticos, constituyendo un buen indicador de biodiversidad. 4. La mayoría de las áreas con interés de conservación máximo se localizan en tramos de cabecera, en el noroeste de la cuenca, con predominio de hábitats tipo como arroyos de montaña. 5. La coincidencia entre las áreas prioritarias de conservación y los ENPs ("Espacios Naturales Protegidos") es de aproximadamente el 67 %, por lo tanto, existe un vacío que representa el 33 % de la superficie considerada como de interés de conservación máximo.
Con este trabajo se pretende identificar las áreas prioritarias de conservación en la Cuenca del ... more Con este trabajo se pretende identificar las áreas prioritarias de conservación en la Cuenca del Río Segura, utilizando los coleópteros acuáticos como herramienta. Se ha empleado el índice denominado Interés de Conservación (IC) (Millán 1991), que atiende a criterios de riqueza y rareza de especies, y es una modificación del índice Rarity Quality Factor (Eyre & Rushton, 1989). Este índice se ha aplicado a la comunidad de Adephaga acuáticos y al total de coleópteros acuáticos, tanto por estaciones (248 y 377) como por cuadrículas UTM de 10 x 10 Km. (116 cuadrículas, aproximadamente el 50% de la superficie total). En función de los valores del IC se han clasificado las estaciones y cuadrículas según su interés de conservación y se han identificado las áreas prioritarias de conservación para la Cuenca del Río Segura. Por último, se ha elaborado una cartografía superponiendo las áreas prioritarias y los Espacios Naturales Protegidos, para determinar el grado de solapamiento existente y detectar vacíos en conservación. Los resultados más destacables son: 1.-Se ha registrado un total de 230 especies de coleópteros acuáticos, aproximadamente el 36 % de la riqueza de la Península Ibérica, de las cuales 32 son endemismos ibéricos, 4 de ellos exclusivos para la Cuenca del Río Segura (Hydraena mecai, H. mandfredjaechi, Limnebius millani y Ochthebius albacetinus). 2.-Dos estaciones, Nacimiento del Río Madera y Chorros del Río Mundo, aparecen siempre dentro de las 10 más valoradas, por lo que merecen una especial atención cara a su conservación. 3. Los Adephaga acuáticos pueden reflejar condiciones ambientales similares al conjunto de los coleópteros acuáticos, constituyendo un buen indicador de biodiversidad. 4. La mayoría de las áreas con interés de conservación máximo se localizan en tramos de cabecera, en el noroeste de la cuenca, con predominio de hábitats tipo como arroyos de montaña. 5. La coincidencia entre las áreas prioritarias de conservación y los ENPs ("Espacios Naturales Protegidos") es de aproximadamente el 67 %, por lo tanto, existe un vacío que representa el 33 % de la superficie considerada como de interés de conservación máximo.
New faunistic and distributional data on aquatic Hemiptera from the Oriental Region of Morocco an... more New faunistic and distributional data on aquatic Hemiptera from the Oriental Region of Morocco and the Moulouya River basin, covering an area of 119,268 km2, are presented. An annotated list of 45 species, 21 genera and 11 families is provided. Nine species are new records for the entire studied area, and two for the Moulouya River basin. We rediscovered Velia noualhieri iberica and Notonecta viridis after eight decades. We also provide novel records for Aphelocheirus pemae and Hebrus atlas, which were recently described from Morocco, and for the invasive corixid Trichocorixa verticalis verticalis. The dominance of species with broad distributions points to the high dispersal dynamics of the Hemiptera community in the study area, similar to that of other areas where a semiarid climate prevails.
This study updates current knowledge of the relationships and geographical distributions of the s... more This study updates current knowledge of the relationships and geographical distributions of the species from the genus Aphelocheirus in the Iberian Peninsula which, until now, have been involved in nomenclatural and taxonomic confusion. The morphological and molecular analyses presented in this study confirm the taxonomic validity of A. murcius and the absence of A. aestivalis in the Iberian Peninsula. The shape of the left paramere emerged as the only valid characteristic to differentiate both species. Specimens of Aphelocheirus from northern Spain, previously identified as A. murcius, formed an independent lineage genetically distinct to A. murcius and A. aestivalis, although morphologically indistinguishable from A. murcius.
Protected area networks represent one of the mainstays of global conservation polices and are 35 ... more Protected area networks represent one of the mainstays of global conservation polices and are 35 therefore central to current efforts to maintain biodiversity. However, a major limitation of most 36 conservation strategies is their bias towards particular taxonomic groups and ecosystems, 37 meaning that many taxa and habitats are often only incidentally protected as a by-product of 38 inclusion within reserves. Here we investigate how effectively protected area networks, not 39 specifically designated for freshwaters, support aquatic biodiversity in the Iberian Peninsula 40 (Spain and Portugal), using data for water beetles, surrogates of overall macroinvertebrate 41 diversity in these habitats. We explore the behaviour of different measures (alpha, beta and 42 gamma) of both taxonomic and functional diversity at different spatial scales. Overall our 43 findings highlight the contrasting performance of reserve systems in the maintenance of either 44 taxonomic or functional diversity, as well as the importance of spatial scale. Iberian reserves 45 perform relatively well in supporting taxonomic diversity of water beetles at the peninsular 46 scale, but the same protected areas poorly represent functional diversity. Such a mismatch 47 cautions against the use of any one diversity component as a surrogate for others, and 48 emphasizes the importance of adopting an integrative approach to biodiversity conservation in 49 aquatic ecosystems. Furthermore, our results often show contrasting patterns at smaller spatial 50 scales, highlighting the need to consider the influence of scale when evaluating the effectiveness 51 of protected area networks.
Transitions from fresh to saline habitats are restricted to a handful of insect lineages, since t... more Transitions from fresh to saline habitats are restricted to a handful of insect lineages, since the colonization of saline waters requires specialized mechanisms to deal with osmotic stress. Previous studies have suggested that tolerance to salinity and desiccation could be mechanistically and evolutionarily linked, but the temporal sequence of these adaptations is not well established for individual lineages. We combined molecular, physiological and ecological data to explore the evolution of desiccation resistance, hyporegulation ability (i.e. the ability to osmoregulate in hyperosmotic media) and habitat transitions in the water beetle genus Enochrus subgenus Lumetus (Hydrophilidae). We tested whether enhanced desiccation resistance evolved before increases in hyporegulation ability or vice versa, or whether the two mechanisms evolved in parallel. The most recent ancestor of Lumetus was inferred to have high desiccation resistance and moderate hyporegulation ability. There were repeated shifts between habitats with differing levels of salinity in the radiation of the group; those to the most saline habitats generally occurring more rapidly than those to less saline ones. Significant and accelerated changes in hyporegulation ability evolved in parallel with smaller and more progressive increases in desiccation resistance across the phylogeny, associated with the colonisation of meso-and hypersaline waters during global aridification events. All species with high hyporegulation ability were also desiccationresistant, but not vice versa. Overall, results are consistent with the hypothesis that desiccation resistance mechanisms evolved first and provided the physiological basis for the development of hyporegulation ability, allowing these insects to colonize and diversify across meso-and hypersaline habitats.
Hydrocarbons are the principal component of insect cuticle and play an important role in maintain... more Hydrocarbons are the principal component of insect cuticle and play an important role in maintaining water balance. Cuticular impermeability could be an adaptative response to salinity and desiccation in aquatic insects; however, cuticular hydrocarbons have been poorly explored in this group and there are no previous data on saline species. We characterized cuticular hydrocarbons of adults and larvae of two saline aquatic beetles, namely Nebrioporus baeticus (Dytiscidae) and Enochrus jesusarribasi (Hydrophilidae), using a gas chromatograph coupled to a mass spectrometer. The CHC profile of adults of both species, characterized by a high abundance of branched alkanes and low of unsaturated alkenes, seems to be more similar to that of some terrestrial beetles (e.g., desert Tenebrionidae) compared with other aquatic Coleoptera (freshwater Dytiscidae). Adults of E. jesusarribasi had longer chain compounds than N. baeticus, in agreement with their higher resistance to salinity and desicc...
Exposing organisms to a particular stressor may enhance tolerance to a subsequent stress, when pr... more Exposing organisms to a particular stressor may enhance tolerance to a subsequent stress, when protective mechanisms against the two stressors are shared. Such cross-tolerance is a common adaptive response in dynamic multivariate environments and often indicates potential co-evolution of stress traits. Many aquatic insects in inland saline waters from Mediterranean-climate regions are sequentially challenged with salinity and desiccation stress. Thus, cross-tolerance to these physiologically similar stressors could have been positively selected in insects of these regions. We used adults of the saline water beetles Enochrus jesusarribasi (Hydrophilidae) and Nebrioporus baeticus (Dytiscidae) to test cross-tolerance responses to desiccation and salinity. In independent laboratory experiments, we evaluated the effects of (i) salinity stress on the subsequent resistance to desiccation and (ii) desiccation stress (rapid and slow dehydration) on the subsequent tolerance to salinity. Survival, water loss and haemolymph osmolality were measured. Exposure to stressful salinity improved water control under subsequent desiccation stress in both species, with a clear cross-tolerance (enhanced performance) in N. baeticus. In contrast, general negative effects on performance were found under the inverse stress sequence. The rapid and slow dehydration produced different water loss and haemolymph osmolality dynamics that were reflected in different survival patterns. Our finding of cross-tolerance to salinity and desiccation in ecologically similar species from distant lineages, together with parallel responses between salinity and thermal stress previously found in several aquatic taxa, highlights the central role of adaption to salinity and co-occurring stressors in arid inland waters, having important implications for the species' persistence under climate change.
A new species of Aphelocheirus (Hemiptera: Heteroptera: Aphelocheiridae) inhabiting riffles of a ... more A new species of Aphelocheirus (Hemiptera: Heteroptera: Aphelocheiridae) inhabiting riffles of a stream in Kerala state in southern India is described. Aphelocheirus kaygieyess n. sp. is diagnosed by widely separated hemelytra and the pattern of dark maculation on the vertex. This species is compared to other Indian species of Aphelocheirus. Seven species of Aphelocheirus are known now from India.
BackgroundDesiccation resistance shapes the distribution of terrestrial insects at multiple spati... more BackgroundDesiccation resistance shapes the distribution of terrestrial insects at multiple spatial scales. However, responses to drying stress have been poorly studied in aquatic groups, despite their potential role in constraining their distribution and diversification, particularly in arid and semi-arid regions.MethodsWe examined desiccation resistance in adults of four congeneric water beetle species (Enochrus, family Hydrophilidae) with contrasting habitat specificity (lenticvs.lotic systems and different salinity optima from fresh- to hypersaline waters). We measured survival, recovery capacity and key traits related to desiccation resistance (fresh mass, % water content, % cuticle content and water loss rate) under controlled exposure to desiccation, and explored their variability within and between species.ResultsMeso- and hypersaline species were more resistant to desiccation than freshwater and hyposaline ones, showing significantly lower water loss rates and higher water ...
Predicting the richness of aquatic beetles and bugs in a semi-arid mediterranean region The south... more Predicting the richness of aquatic beetles and bugs in a semi-arid mediterranean region The southeastern Iberian Peninsula is a semi-arid region recognised as an area of high aquatic biodiversity. Water beetles (Coleoptera) and water bugs (Hemiptera) are two of the region's most thoroughly studied insect groups. An exhaustive database of aquatic beetles and bugs from the Region of Murcia (SE Spain) and a set of 33 variables were employed for two related purposes: a) to describe the sampling effort conducted in the study area on these groups in order to identify zones with reliable inventories and b) with this information as a base, to forecast the distribution of species richness for each group. Theoretical estimates were based on the Clench function applied to the accumulated number of samples and were constructed with general linear models (GLM). The following results were obtained: 1) the percentage of grid cells that can be considered to be well sampled in the study area (143 10 × 10 km UTM grid cells) is approximately 14 % for beetles and 22 % for bugs; 2) well-surveyed cells are evenly distributed according to the previously defined physioclimatic subareas, which enable the use of these grid cells for modelling the richness distribution; and 3) a more accurate picture of the actual richness patterns for both groups is shown by the analysis. These results were combined to identify key areas where future sampling efforts must be focused.
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