Ethological uniqueness of a damselfly with no near relatives: the relevance of behaviour as part of biodiversity

Singularidad etológica de una damisela sin parientes cercanos: la importancia del comportamiento como parte de la biodiversidad Las especies taxonómicamente aisladas pueden aportar caracteres únicos a la diversidad biológica, particularmente en el ámbito de la diversidad etológica. Para comprobar esta idea, analizamos el comportamiento territorial y reproductor de Pseudolestes mirabilis (Zygoptera, Pseudolestidae), una damisela endémica de la isla de Hainan, en China, y el único representante de su familia. Nuestra hipótesis era que la singularidad de este taxón sería evidente en su comportamiento. Encontramos que los combates agonísticos entre machos fueron generalmente muy cortos (menos de 2 min) y consistieron en un vuelo de presentación cara a cara a una distancia cercana usando únicamente las alas anteriores. Ningún otro odonato vuela solo con dos alas en luchas territoriales. Además, una pequeña proporción de las peleas se intensificó y duró alrededor de una hora; en estas peleas los machos mostraron de forma evidente sus alas posteriores coloreadas. Los machos también se enfrentaron de manera similar, aunque durante poco tiempo, a las avispas (Eustenogaster nigra) que utilizaron el mismo microhábitat. El hecho de que se encontraran pocas hembras limitó la frecuencia de cópula, lo que determinó que la mayoría de los machos no se apareara durante todo el día. A diferencia de lo que cabría esperar para una libélula con alas coloreadas, el cortejo anterior a la cópula fue prácticamente inexistente, lo que sugiere que la selección intrasexual está detrás de la evolución de las alas coloreadas en esta especie. La cópula duró un promedio de siete minutos y estuvo compuesta por una primera etapa de eliminación del esperma de los rivales (64 % de esperma retirado) y una segunda etapa de inseminación. De acuerdo con nuestra hipótesis inicial, el comportamiento de cópula fue único: los machos no transfirieron el esperma a su vesícula antes de cada apareamiento, sino que lo hicieron después de la cópula, un comportamiento que no se puede explicar fácilmente. Estas características exclusivas apuntan a la importancia de esta especie como taxón excepcional que merece una alta prioridad de conservación.Taxonomically isolated species may contribute unique characters to biological diversity, particularly at the level of ethodiversity. To test this idea, we analysed the territorial and reproductive behaviour of Pseudolestes mirabilis(Zygoptera, Pseudolestidae), an endemic damselfly from Hainan island, China, and the only representative of its family. Our hypothesis was that the uniqueness of this taxon would be evident in its behaviour. We found that the agonistic encounters between males were usually very short (less than 2 min) and consisted of a face–to–face display with both males maintaining a close distance while flying using only the forewings. No other odonate flies with only two wings in territorial contests. Furthermore, a small proportion of fights were escalated and lasted about one hour, with clear exhibition of the coloured hindwings. Males also confronted wasps (Eustenogaster nigra) that used the same microhabitat in a similar way, albeit for short time. Females were found in low numbers. This limited copulatory frequency and most males did not mate in the whole day. Unexpectedly for a damselfly with coloured wings, precopulatory courtship was almost absent, suggesting that intrasexual selection is behind the evolution of coloured wings in this species. Copulation lasted an average of seven minutes, with a first stage of rivals’ sperm removal (64 % of sperm removed) and a second stage of insemination. In agreement with our initial hypothesis, copulatory behaviour was unique: males did not translocate sperm to their vesicle before each mating but translocated sperm after copulation, a behaviour that cannot be easily explained. These exclusive characteristics point to the relevance of this species as an exceptional taxon that merits high conservation priority.Singularidad etológica de una damisela sin parientes cercanos: la importancia del comportamiento como parte de la biodiversidad Las especies taxonómicamente aisladas pueden aportar caracteres únicos a la diversidad biológica, particularmente en el ámbito de la diversidad etológica. Para comprobar esta idea, analizamos el comportamiento territorial y reproductor de Pseudolestes mirabilis (Zygoptera, Pseudolestidae), una damisela endémica de la isla de Hainan, en China, y el único representante de su familia. Nuestra hipótesis era que la singularidad de este taxón sería evidente en su comportamiento. Encontramos que los combates agonísticos entre machos fueron generalmente muy cortos (menos de 2 min) y consistieron en un vuelo de presentación cara a cara a una distancia cercana usando únicamente las alas anteriores. Ningún otro odonato vuela solo con dos alas en luchas territoriales. Además, una pequeña proporción de las peleas se intensificó y duró alrededor de una hora; en estas peleas los machos mostraron de forma evidente sus alas posteriores coloreadas. Los machos también se enfrentaron de manera similar, aunque durante poco tiempo, a las avispas (Eustenogaster nigra) que utilizaron el mismo microhábitat. El hecho de que se encontraran pocas hembras limitó la frecuencia de cópula, lo que determinó que la mayoría de los machos no se apareara durante todo el día. A diferencia de lo que cabría esperar para una libélula con alas coloreadas, el cortejo anterior a la cópula fue prácticamente inexistente, lo que sugiere que la selección intrasexual está detrás de la evolución de las alas coloreadas en esta especie. La cópula duró un promedio de siete minutos y estuvo compuesta por una primera etapa de eliminación del esperma de los rivales (64 % de esperma retirado) y una segunda etapa de inseminación. De acuerdo con nuestra hipótesis inicial, el comportamiento de cópula fue único: los machos no transfirieron el esperma a su vesícula antes de cada apareamiento, sino que lo hicieron después de la cópula, un comportamiento que no se puede explicar fácilmente. Estas características exclusivas apuntan a la importancia de esta especie como taxón excepcional que merece una alta prioridad de conservación

Male coercion and convenience polyandry in a calopterygid damselfly

Copulation in odonates requires female cooperation because females must raise their abdomen to allow intromission. Nevertheless in Calopteryx haemorrhoidalis haemorrhoidalis (Odonata) males commonly grasp ovipositing females and apparently force copulations. This has been interpreted as a consequence of extreme population density and male-male competition. We studied this behavior at two sites on a river that had different densities over three years. As predicted, at high densities most matings were forced (i.e. not preceded by courtship), but at low density most were preceded by courtship. Courtship matings were shorter at high density, but density did not affect the duration of forced matings. Females cooperated in forced matings even if they had very few mature eggs. Furthermore, females mated more times if they experienced higher male harassment during oviposition, and at low density second and subsequent matings were more likely to be forced. We interpret these results to mean that females engage in “convenience polyandry”, because they gain more by accepting copulation than by resisting males. The results also suggest that females might trade copulations for male protection, because under extreme population density harassment by males is so intense that they can impede oviposition

Eucalypt plantations reduce the diversity of macroinvertebrates in small forested streams

Las plantaciones de eucaliptos reducen la diversidad de macroinvertebrados en pequeños arroyos forestales Los usos del suelo de una cuenca hidrológica ejercen un efecto importante en la estructura y el funcionamiento de sus ecosistemas fluviales. Los cambios en la composición de las comunidades de plantas ripícolas modifican la cantidad, calidad y estacionalidad de las entradas de materia y energía a los ríos, lo que afecta a la colonización y actividad de sus comunidades de macroinvertebrados. El principal objetivo de este estudio es analizar los efectos de los cambios en el uso del suelo y, en particular, de las plantaciones de eucalipto, en las comunidades de macroinvertebrados de 16 arroyos de cabecera. Se contaron macroinvertebrados y se identificaron hasta el nivel de familia. Los usos del suelo se clasificaron en cinco categorías utilizando fotografías aéreas: bosque autóctono, eucaliptal, zona agrícola, matorral y zona urbana. Observamos que la diversidad de macroinvertebrados aumentó con el tamaño de la cuenca y con la proporción de superficie de la cuenca cubierta por bosque autóctono, lo cual resultó estar inversamente correlacionado con la superficie ocupada por eucaliptales. La riqueza de macroinvertebrados disminuyó a medida que aumentaba el suelo ocupado por eucaliptales y se produjo una tendencia similar con la diversidad. Además, nuestras observaciones indican que los arroyos cuyas áreas de captación están cubiertas principalmente por eucaliptales presentan una mayor probabilidad de secarse completamente en verano. Esta observación añade un nuevo indicio concordante con otros estudios que concluyen que las plantaciones de árboles de rápido crecimiento afectan a los recursos hídricos, que constituyen un servicio ecosistémico importante en el contexto del calentamiento de la Tierra. Con vistas a minimizar los efectos de la silvicultura industrial, se sugiere que mantener o recuperar bosques ribereños podría mitigar las repercusiones de los monocultivos intensivos de eucaliptos.Land use patterns of a river basin have a significant effect on the structure and function of river ecosystems. Changes in the composition of riparian plant communities modify the quantity, quality and seasonality of leaf–litter inputs, determining changes in macroinvertebrate colonization and activity. The main goal of this study was to test the effect of land–use modifications, and particularly the impact of eucalypt plantations, on the macroinvertebrate communities of sixteen headwater streams. Macroinvertebrates were counted and identified to family level. Land uses were classified in five categories using aerial photography: native forest, eucalypt plantations, agricultural land, shrubland, and urban areas. We found that macroinvertebrate diversity increased with basin size and with the proportion of basin covered by native forest. This variable correlated negatively with the land occupied by eucalypt plantations. Macroinvertebrate richness diminished with the increase of land surface covered by eucalypt plantations, and a similar tendency was observed with diversity. Furthermore, streams whose drainage basin was mainly covered by Eucalyptus were more likely to dry up in summer. This observation adds to evidence from previous studies that concluded that fast–growing tree plantations affect hydric resources, an important ecosystem service in the context of global warming. To minimize the impact of industrial sylviculture, we suggest that maintaining and/or restoring riparian forests could mitigate the effects of intensive eucalypt monocultures.Las plantaciones de eucaliptos reducen la diversidad de macroinvertebrados en pequeños arroyos forestales Los usos del suelo de una cuenca hidrológica ejercen un efecto importante en la estructura y el funcionamiento de sus ecosistemas fluviales. Los cambios en la composición de las comunidades de plantas ripícolas modifican la cantidad, calidad y estacionalidad de las entradas de materia y energía a los ríos, lo que afecta a la colonización y actividad de sus comunidades de macroinvertebrados. El principal objetivo de este estudio es analizar los efectos de los cambios en el uso del suelo y, en particular, de las plantaciones de eucalipto, en las comunidades de macroinvertebrados de 16 arroyos de cabecera. Se contaron macroinvertebrados y se identificaron hasta el nivel de familia. Los usos del suelo se clasificaron en cinco categorías utilizando fotografías aéreas: bosque autóctono, eucaliptal, zona agrícola, matorral y zona urbana. Observamos que la diversidad de macroinvertebrados aumentó con el tamaño de la cuenca y con la proporción de superficie de la cuenca cubierta por bosque autóctono, lo cual resultó estar inversamente correlacionado con la superficie ocupada por eucaliptales. La riqueza de macroinvertebrados disminuyó a medida que aumentaba el suelo ocupado por eucaliptales y se produjo una tendencia similar con la diversidad. Además, nuestras observaciones indican que los arroyos cuyas áreas de captación están cubiertas principalmente por eucaliptales presentan una mayor probabilidad de secarse completamente en verano. Esta observación añade un nuevo indicio concordante con otros estudios que concluyen que las plantaciones de árboles de rápido crecimiento afectan a los recursos hídricos, que constituyen un servicio ecosistémico importante en el contexto del calentamiento de la Tierra. Con vistas a minimizar los efectos de la silvicultura industrial, se sugiere que mantener o recuperar bosques ribereños podría mitigar las repercusiones de los monocultivos intensivos de eucaliptos

Incidence of Anagrus obscurus (Hymenoptera: Mymaridae) egg parasitism on Calopteryx haemorrhoidalis and Platycnemis pennipes (Odonata: Calopterygidae, Platycnemididae) in Italy

Very little is known about the incidence of egg parasitoids in odonates, perhaps because Odonata eggs are well protected in stems or leaves, sometimes below water. In Central Italy (Pontecorvo, Frosinone province) two damselflies, Calopteryx haemorrhoidalis and Platycnemis pennipes occur at high densities. In August 2007 we collected 30 stems of the aquatic plant Potamogeton sp. used as substrate for oviposition and incubated eggs in the laboratory. Most stems (24 for C. haemorrhoidalis and 23 for P. pennipes) contained odonata eggs. Parasitoids emerged from 12 stems, with a mean parasitism of 2% for C. haemorrhoidalis and 6% for P. pennipes, and a maximum of 14% and 50%, respectively. Furthermore, we observed egg-laying of 19 females of C. haemorrhoidalis and 11 of P. pennipes, and marked the stems where oviposition was observed. Clutches remained in the river for 5 days and were then collected and incubated. Parasitoids emerged from 11 stems out of 30, with an average parasitism of 8% for C. haemorrhoidalis and 3% for P. pennipes (maximum of 50% and 29%, respectively). All parasitoids belonged to the family Mymaridae, and were identified as Anagrus (Anagrus) obscurus Förster, 1861, sensu Soyka, 1955. This is the first time that such species is described as an egg parasitoid of odonates, and that an egg parasitoid of C. haemorrhoidalis and P. pennipes is identified. Our data suggest that egg parasitism might be a significant selective factor for both odonates in the studied locality, affecting female oviposition behaviour

Supervivencia y longevidad de las libélulas del neotrópico (Odonata, Polythoridae)

Survival and longevity in neotropical damselflies (Odonata, Polythoridae). Longevity among insect orders varies greatly, and has mainly been studied in insects in temperate biomes, where seasonality determines high synchronization of reproductive activities and limits lifespan. Most forest damselflies in tropical regions have low population densities and are almost never observed in copula. We hypothesized that selection will favour a high survival rate and hence high lifespan, allowing the animals to be ready for the occasional events that favour reproduction. We studied two neotropical damselflies, Polythore mutata and P. derivata, in Ecuador, using mark–recapture methods. We found that sex affected the rate of recapture, but daily survival rate was affected by sex only in one population. We found evidence that suggests stabilizing or directional selection on body size. The maximum lifespan was 54–63 days. We conclude that the survival rate of Polythore damselflies in tropical forests is comparable to that of similar damselflies in temperate zones. © 2019. Museu de Ciències Naturals de Barcelona. All rights reserved

Maternal genetic inheritance of red pericarp in the grain of maize

The diversity of colors in the grain of corn is wide, from whites to blacks and including a continuum of various shades of yellows, pinks, reds, purples and blues. The most abundant commercial colors are yellow and white, however other colors have become more important because of the presence of pigments to which are attributed favorable effects as a food. The pigments are also considered natural barriers of the grain against the invasion of pests and diseases in the production fields. The colors of the grain of corn occur in three different parts of the seed: the cover of the grain or pericarp, derived from the maternal tissue, with a diploid genetic content; the endo-sperm, including the aleurone layers that are cells in the grain immediately below the pericarp with a chromosome content of 3n; and the embryo, with a genetic content of 2n. The red color considered in this study is present in the pericarp ignoring possible effects in other tissues of grain and other organs of the plant. In this study, we used materials with colorless or red pericarp, and white or yellow endosperm; with the purpose of describing the type of inheritance of this character in the grain of corn. The results indicated a maternal genetic inheritance with classical complete dominance of the red color of pericarp over the clear or transparent phenotype, where the red color of the grains on ear is determined by the genotype of the mother grain but not by the seed embryo genotypes, which is characterized by uniformity of grain color of the ear. This type of inheritance could be useful in the development of pigmented varieties of higher food quality for humans

Influence of operational parameters on photocatalytic amitrole degradation using nickel organic xerogel under UV irradiation

The objectives of this study were to analyze the influence of different operational variables and to determine the time course of total organic carbon (TOC) and medium toxicity during amitrole (AMT) photodegradation in the presence of Ni xerogel (X-Ni) as photocatalyst. A further study objective was to analyze the influence of the type of water on the photodegradation process. Results show that the degradation rate is directly proportional to the initial X-Ni concentration up to a maximum of 250 mg/L with a slight decrease thereafter, indicating progressive photon absorption saturation of the catalyst for a given incident radiation flow. At concentrations close to 250 mg/L X-Ni, the AMT photodegradation rate is not affected by further increases in X-Ni concentration. In addition, AMT photolysis is highly pH-dependent and is generally favored at pH values at which AMT is in its ionic form. The increase observed in AMT degradation rate under alkaline conditions can be attributed to the higher generation of radicals. The presence of chloride reduces the AMT degradation rate, because Cl− anions behave as h+ and radical scavengers. The degradation rate is also decreased by addition to the medium of organic matter, which acts as a filter. The behavior of TOC removal kinetics during AMT degradation in the presence of X-Ni is similar to that observed for AMT degradation kinetics. Finally, we highlight that photocatalysis is more effective in ultrapure water than in wastewater or tap water. In all systems, the optimal catalyst concentration is 250 mg/L. The medium toxicity increases with longer treatment time, indicating the formation of by-products that are smaller than AMT and can more readily penetrate the cell.Financial support provided by the Ministerio de Ciencia e Innovación (Spain) and FEDER (Projects CTQ-2011-29035-C02-01 and CTQ-2011-29035- C02-02), and by the University of Jaén (Project UJA 2015/06/01)

Environmental and Climatic Determinants of Molecular Diversity and Genetic Population Structure in a Coenagrionid Damselfly

Identifying environmental factors that structure intraspecific genetic diversity is of interest for both habitat preservation and biodiversity conservation. Recent advances in statistical and geographical genetics make it possible to investigate how environmental factors affect geographic organisation and population structure of molecular genetic diversity within species. Here we present a study on a common and wide ranging insect, the blue tailed damselfly Ischnuraelegans, which has been the target of many ecological and evolutionary studies. We addressed the following questions: (i) Is the population structure affected by longitudinal or latitudinal gradients?; (ii) Do geographic boundaries limit gene flow?; (iii) Does geographic distance affect connectivity and is there a signature of past bottlenecks?; (iv) Is there evidence of a recent range expansion and (vi) what is the effect of geography and climatic factors on population structure? We found low to moderate genetic sub-structuring between populations (mean FST = 0.06, Dest = 0.12), and an effect of longitude, but not latitude, on genetic diversity. No significant effects of geographic boundaries (e.g. water bodies) were found. FST-and Dest-values increased with geographic distance; however, there was no evidence for recent bottlenecks. Finally, we did not detect any molecular signatures of range expansions or an effect of geographic suitability, although local precipitation had a strong effect on genetic differentiation. The population structure of this small insect has probably been shaped by ecological factors that are correlated with longitudinal gradients, geographic distances, and local precipitation. The relatively weak global population structure and high degree of genetic variation within populations suggest that I. elegans has high dispersal ability, which is consistent with this species being an effective and early coloniser of new habitats

Turtle Carapace Anomalies: The Roles of Genetic Diversity and Environment

Background: Phenotypic anomalies are common in wild populations and multiple genetic, biotic and abiotic factors might contribute to their formation. Turtles are excellent models for the study of developmental instability because anomalies are easily detected in the form of malformations, additions, or reductions in the number of scutes or scales. Methodology/Principal Findings: In this study, we integrated field observations, manipulative experiments, and climatic and genetic approaches to investigate the origin of carapace scute anomalies across Iberian populations of the European pond turtle, Emys orbicularis. The proportion of anomalous individuals varied from 3 % to 69 % in local populations, with increasing frequency of anomalies in northern regions. We found no significant effect of climatic and soil moisture, or climatic temperature on the occurrence of anomalies. However, lower genetic diversity and inbreeding were good predictors of the prevalence of scute anomalies among populations. Both decreasing genetic diversity and increasing proportion of anomalous individuals in northern parts of the Iberian distribution may be linked to recolonization events from the Southern Pleistocene refugium. Conclusions/Significance: Overall, our results suggest that developmental instability in turtle carapace formation might be caused, at least in part, by genetic factors, although the influence of environmental factors affecting the developmental stability of turtle carapace cannot be ruled out. Further studies of the effects of environmental factors, pollutants an