Hasil untuk "Natural history (General)"

Dewei Peng, Xiaoli He, Bowen Ren et al.

Abstract Background High uric acid levels play a critical role in cardiovascular disease pathophysiology, being closely linked to their occurrence, progression, and prognosis. To enhance prevention and treatment of hyperuricemia-related cardiovascular diseases, understanding underlying mechanisms and identifying novel therapeutic targets are essential. Methods A hyperuricemic mouse model was established, and transcriptomic analysis of myocardial tissue was conducted using RNA sequencing. The role of HMGCS2 in hyperuricemia-induced cardiomyocytes was investigated through HMGCS2 knockout. The transcriptional regulation of HMGCS2 by STAT3 was explored via STAT3 knockdown, overexpression, and dual-luciferase reporter assays. To further elucidate the role of the JAK2/STAT3/hmgcs2 signaling pathway in hyperuricemia-induced cardiomyocytes, we overexpressed HMGCS2 while intervening in the JAK2/STAT3 pathway in vitro. The therapeutic potential of targeting the JAK2/STAT3/HMGCS2 pathway was evaluated in hyperuricemic mice using STAT3 and JAK inhibitors to assess effects on cardiac dysfunction. Results RNA sequencing showed significant upregulation of HMGCS2 mRNA in hyperuricemic mouse cardiac tissue. Increased HMGCS2 protein levels were observed in cardiac tissue and AC16 cardiomyocytes. HMGCS2 knockdown alleviated uric acid-induced mitochondrial dysfunction, oxidative stress, and abnormal energy metabolism in AC16 cardiomyocytes. And high uric acid levels activate the IL-6/JAK2/STAT3 signaling pathway in AC16 cardiomyocytes, which regulates HMGCS2 expression. By modulating JAK2 and STAT3 expression and subsequently overexpressing HMGCS2, we identified the involvement of the JAK2/STAT3/HMGCS2 pathway in uric acid-induced mitochondrial dysfunction, oxidative stress, and energy metabolism abnormalities in AC16 cardiomyocytes. In vitro experiments demonstrated that intervention with the ruxolitinib and S3I-201 could ameliorate mitochondrial dysfunction, oxidative stress, and ATP levels in the heart tissue of hyperuricemic mice. Moreover, these treatments also reversed cardiac function abnormalities. Conclusions The JAK2/STAT3/HMGCS2 pathway may contributes to uric acid-induced cardiac dysfunction by affecting mitochondrial function, oxidative stress, and ATP metabolism, offering a potential therapeutic strategy for mitigating high uric acid-induced cardiac damage. Graphical Abstract Model of hyperuricemia-induced mitochondrial dysfunction and oxidative stress in cardiomyocytes involving JAK2/STAT3/HMGCS2 signaling.

Hakan Topal

This article examines how artistic practices respond to the emergence of a “negative community” after a disaster, where people are bound together by displacement, abandonment, and infrastructural control rather than choice or solidarity. Drawing on fieldwork in coastal Japan following the 2011 earthquake, tsunami, and nuclear accident, this article reflects on how art can resist the reduction of catastrophe to either spectacle or state‐managed recovery. Through practices of observation, witnessing, and collective engagement, art creates vital spaces of proximity, care, and dissent. In doing so, it unsettles imposed forms of community and opens possibilities for imagining a new social life beyond the structures of ruin and control.

Fa Zheng, Zanhui Huang, Zanhui Huang et al.

IntroductionChina's rapid economic growth has led to escalating environmental pollution, significantly impacting mangrove ecosystems. The persistence and response to pollution in mangrove ecosystems involve multiple processes, including the accumulation of contaminants in sediments, their transport in plants, and their accumulation in other organisms. However, comprehensive studies on the multidimensional interactions among these processes are limited. MethodsThis study investigated two mangrove forest areas in Hainan, which were categorized according to the type of mangrove forest cover: planted forests and natural forests. Thirty sampling sites were established to collect data on benthic organisms and their sediment characteristics. ResultsElemental As showed moderate, ongoing pollution. The distribution of species in the two regions showed significant population differences. The benthic population density in the natural forest was significantly lower than that in the planted forest, which was mainly due to the prevalence of Batillaria cumingi, and biodiversity indices and habitats in the natural forest were superior to those in the planted forest, which mainly depended on the degree of anthropogenic disturbance. Total phosphorus, nitrogen, dissolved solids, Hg, and sand grains were the most important variables. DiscussionTotal phosphorus and total nitrogen were the most important environmental factors affecting community composition, while total dissolved solids influenced overall changes in species composition, highlighting the significant influence of the type of mangrove cover on sediment pollution and environmental factors, leading to significant changes in the biomass and density of benthic organisms. This study emphasizes the complex interactions among sediment contamination, mangrove cover, and benthic communities, providing a three-dimensional view of the distribution patterns of mangrove contamination.

C. Isabel Nuñez Lendo, David J. Suggett, David J. Suggett et al.

Coral carbonate production is fundamental to reef accretion and, consequently, the preservation of essential reef ecosystem services, such as wave attenuation and sustained reef biodiversity. However, the unprecedented loss of coral reefs from anthropogenic impacts has put these valuable ecosystem services at risk. To counteract this loss, active rehabilitation of degraded reef sites has accelerated globally. A variety of restoration practices exist, tailored to local site needs and reef types. For sites where there is a significant unconsolidated substrate, Mars Assisted Reef Restoration System (MARRS, or “Reef Stars”) has been utilised to contribute toward rubble stabilisation and reef accretion. However, the effect of the Reef Stars on the local carbonate budgets and structural complexity has not been assessed. For that purpose, we assess coral cover and reef complexity through a census-based approach to identify the contribution of carbonate producers and eroders alongside studying coral skeletal properties to estimate current carbonate budgets on a rehabilitated site compared to natural unrehabilitated reef and rubble patches on the mid-Great Barrier Reef. Our research identified positive ecological processes and ecological functions such as increased carbonate budget, coral cover and structural complexity at the restored site compared to the non-intervened reef and rubble patches. In general, no impacts on skeletal rigour relative to this active reef restoration were found for two key coral species and the Acropora rubble for most of the skeletal traits. However, Pocillopora damicornis hardness seemed to decrease on the restored site compared to the other sites, demonstrating different performances of coral species during restoration activities that should be considered to maximise return-on-effort of restoration activities. Overall, our data demonstrate that consideration of carbonate budgets is important for measuring success of coral restoration initiatives and that coral restoration can be a relevant tool to recover lost local carbonate budgets.

Kevin Madrigal, Santiago Zaragoza-Caballero, Andrés Ramírez-Ponce

The endemic Mexican genus Lamoana Casey, 1915 stat. rev. is revalidated through a comparative morphological analysis of both male genitalia and somatic characters of all genera with perpendicular parameres. A comparative study and general description of the basic patterns in the morphology of the genitalia for the American genera are provided. A full redescription of the genus and a redescription of L. villosella (Blanchard, 1851) comb. rev. is provided herein, with the addition of generic and specific diagnostic characters and data about its geographical distribution. Further, possible relationships at generic level among American genera are provided. With this study, the number of Anomalini genera known for America and Mexico is now elevated to 17 and 14, respectively.

Siyu Yan, Binbin Li, Kunxia Yu et al.

[Objective] The erosion intensity and the causes of erosion of the production roads after rainstorm in the small watershed at Xiji County, Ningxia Hui Autonomous Region were explored in order to provide a theoretical basis for improving the situation of soil erosion and improving the construction and maintenance of water and soil conservation projects in the future. [Methods] From July 25 to 29, 2022, Soil and Water Conservation Monitoring Center of the Ministry of Water Resources organized a comprehensive survey on soil and water conservation of the "7·13" rainstorm at Xiji County, Ningxia Hui Autonomous Region. The environment and erosion status of the production road in the small watershed of the Wushicha small watershed were investigated and the erosion intensity was calculated by using the "section method". The erosion intensity status and the causes of erosion were analyzed. [Results] ① The rainfall, the characteristics of road and the human activities are the main influencing factors of the production roads erosion in the Wushicha small watershed. Each road shows different erosion patterns, among which the lower reaches of the small watershed, along the runoff direction and with low vegetation coverage are seriously eroded. ② The road erosion modulus of small watershed is analyzed and calculated. The calculated value of "section method" is 1 054.49 t/km2, and the measured value of 3D image is 1 277.91 t/km2. The damage rate of the survey section is 53.39%. [Conclusion] It is necessary and effective to implement soil and water conservation measures. Good soil and water conservation measures and high vegetation coverage rate can effectively prevent the occurrence of soil and water loss on production roads.

Paulo F. Lagos, Alva Curtsdotter, Antonio Agüera et al.

A Dynamic Energy Budget (DEB) model is applied to predict rapid metabolic shifts in an ecologically important krill, Nyctiphanes australis, in response to temperature and ultraviolet radiation (UVR). Specifically, we predict changes in fatty acids, amino acids and respiration rate in response to several light and temperature treatments. Environmental variability can alter the metabolic equilibrium and the mechanisms marine ectotherms used to obtain energy, which is a topical point given the current level of environmental change. Environmental variability also includes multiple stressors, which can have additive, antagonistic or synergistic effects on metabolism. In consequence, disentangling and quantifying the effects of multiple stressors on metabolism and the energy balance of ecthothermal species, such as krill, can be challenging. Here we apply a DEB model to direct measurements of fatty acids, amino acids and respiration rate of krill experimentally exposed simultaneously to several doses of UVR and temperatures. We found that on average light escalates metabolic rates by a factor of two, and temperature has an effect 1.35 times greater than the effect of light over respiration rates at temperatures from 9 to 19°C. The DEB model predicted shifts in metabolic function and indicated that the combined effect of light and elevated temperatures decrease the total of fatty acid concentrations at a higher rate than amino acids when krill are exposed to environmentally relevant temperatures and light treatments. Our results demonstrate that, when krill experience warmer conditions and higher levels of solar radiation, the mobilization of energy-relevant metabolites from the reserves increases by up to 36% and increase the total energetic cost by up to 45%. These findings suggest that ectothermal species with a fast metabolism, such as krill, quickly deplete energy reserves to compensate for changes in the environment. This renders krill susceptible to the effects of climate variability if the current climatic trend for the region continues to show temperature increases, even if solar radiation levels remain unchanged.

Yi-Chen Cheng, Sen Jan, Chung-Chi Chen

Swordtip squid (Uroteuthis edulis) is a primary target species of the commercial fishery in the southern East China Sea (ECS), and they normally migrate to a quasi-permanent upwelling zone (called a cold dome) off northeastern Taiwan for spawning and growth during spring (March–May) and fall (October–December) in a year. We examined the connection of the variability in its standardized annual catch per unit effort (CPUE) during 2009–2017 in regard to the physical processes on the southern shelf of the ECS using temperature and wind observations from an isle north of Taiwan (Peng-jia-yu) as well as satellite sea surface temperature and absolute geostrophic velocity. The annual CPUE is positively correlated with the daily temperature anomaly at Peng-jia-yu in the cold dome in October of the previous year and April of the year. A warmer environment favors the recruitment and consequently the catch of the swordtip squid. During the spawning periods of the 9 years, the warm water carried by the Kuroshio frequently intruded atop the cold dome, which benefited the growth of the larvae and consequently helped maintain a certain value of the standardized annual CPUE. The anomalously low CPUE in 2012 and 2016 is attributed to the blocking of the Kuroshio intrusion due to cold and less salty China Coastal Water atop the cold dome in the spring spawning of 2012 and 2016. Based on the velocity strength in the cold dome and in a specified shelf region together with the daily temperature anomaly at Peng-jia-yu, an occupation intensity factor is used to evaluate the dominance of warm Kuroshio water and cold shelf water in the cold dome, which could help predict annual catches.

Kerry-Ann van der Walt, Kerry-Ann van der Walt, Warren M. Potts et al.

Climate change not only drives increases in global mean ocean temperatures, but also in the intensity and duration of marine heatwaves (MHWs), with potentially deleterious effects on local fishes. A first step to assess the vulnerability of fishes to MHWs is to quantify their upper thermal thresholds and contrast these limits against current and future ocean temperatures during such heating events. Heart failure is considered a primary mechanism governing the upper thermal limits of fishes and begins to occur at temperatures where heart rate fails to keep pace with thermal dependency of reaction rates. This point is identified by estimating the Arrhenius breakpoint temperature (TAB), which is the temperature where maximum heart rate (fHmax) first deviates from its exponential increase with temperature and the incremental Q10 breakpoint temperature (TQB), which is where the Q10 temperature coefficient (relative change in heart rate for a 10°C increase in temperature) for fHmax abruptly decreases during acute warming. Here we determined TAB, TQB and the temperature that causes cardiac arrhythmia (TARR) in adults of the marine sparid, Diplodus capensis, using an established technique. Using these thermal indices results, we further estimated adult D. capensis vulnerability to contemporary MHWs and increases in ocean temperatures along the warm-temperate south-east coast of South Africa. For the established technique, we stimulated fHmax with atropine and isoproterenol and used internal heart rate loggers to measure fHmax under conditions of acute warming in the laboratory. We estimated average TAB, TQB, and TARR values of 20.8°C, 21.0°C, and 28.3°C. These findings indicate that the physiology of D. capensis will be progressively compromised when temperatures exceed 21.0°C up to a thermal end-point of 28.3°C. Recent MHWs along the warm-temperate south-east coast, furthermore, are already occurring within the TARR threshold (26.6–30.0°C) for cardiac function in adult D. capensis, suggesting that this species may already be physiologically compromised by MHWs. Predicted increases in mean ocean temperatures of a conservative 2.0°C, may further result in adult D. capensis experiencing more frequent MHWs as well as a contraction of the northern range limit of this species as mean summer temperatures exceed the average TARR of 28.3°C.

Huw J. Griffiths, Paul Anker, Katrin Linse et al.

The seafloor beneath floating ice shelves accounts roughly a third of the Antarctic’s 5 million km2 of continental shelf. Prior to this study, our knowledge of these habitats and the life they support was restricted to what has been observed from eight boreholes drilled for geological and glaciological studies. The established theory of sub-ice shelf biogeography is that both functional and taxonomic diversities decrease along a nutrient gradient with distance from the ice shelf front, resulting in a depauperate fauna, dominated by mobile scavengers and predators toward the grounding line. Mobile macro-benthic life and mega-benthic life have been observed as far as 700 km under an ice shelf. New observations from two boreholes in the Filchner-Ronne Ice Shelf challenge the idea that sessile organisms reduce in prevalence the further under the ice you go. The discovery of an established community consisting of only sessile, probably filter feeding, organisms (sponges and other taxa) on a boulder 260 km from the ice front raises significant questions, especially when the local currents suggest that this community is somewhere between 625 km and 1500 km in the direction of water flow from the nearest region of photosynthesis. This new evidence requires us to rethink our ideas with regard to the diversity of community types found under ice shelves, the key factors which control their distribution and their vulnerability to environmental change and ice shelf collapse.

Emma Kirwin Emma Facca

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Kirsty A. McQuaid, Martin J. Attrill, Malcolm R. Clark et al.

Extractive activities in the ocean are expanding into the vast, poorly studied deep sea, with the consequence that environmental management decisions must be made for data-poor seafloor regions. Habitat classification can support marine spatial planning and inform decision-making processes in such areas. We present a regional, top–down, broad-scale, seafloor-habitat classification for the Clarion-Clipperton Fracture Zone (CCZ), an area targeted for future polymetallic nodule mining in abyssal waters in the equatorial Pacific Ocean. Our classification uses non-hierarchical, k-medoids clustering to combine environmental correlates of faunal distributions in the region. The classification uses topographic variables, particulate organic carbon flux to the seafloor, and is the first to use nodule abundance as a habitat variable. Twenty-four habitat classes are identified, with large expanses of abyssal plain and smaller classes with varying topography, food supply, and substrata. We then assess habitat representativity of the current network of protected areas (called Areas of Particular Environmental Interest) in the CCZ. Several habitat classes with high nodule abundance are common in mining exploration claims, but currently receive little to no protection in APEIs. There are several large unmanaged areas containing high nodule abundance on the periphery of the CCZ, as well as smaller unmanaged areas within the central CCZ, that could be considered for protection from mining to improve habitat representativity and safeguard regional biodiversity.

Nicholas Baetge, Jason R. Graff, Michael J. Behrenfeld et al.

The annual North Atlantic phytoplankton bloom represents a hot spot of biological activity during which a significant fraction of net community production (NCP) can be partitioned into dissolved organic carbon (DOC). The fraction of seasonal NCP that is not respired by the heterotrophic bacterial community and accumulates as seasonal surplus DOC (ΔDOC) in the surface layer represents DOC export potential to the upper mesopelagic zone, and in the North Atlantic this is facilitated by winter convective mixing that can extend to depths > 400 m. However, estimates of ΔDOC and vertical DOC export for the western North Atlantic remain ill-constrained and the influence of phytoplankton community structure on the partitioning of seasonal NCP as ΔDOC is unresolved. Here, we couple hydrographic properties from autonomous in situ sensors (ARGO floats) with biogeochemical data from two meridional transects in the late spring (∼44–56°N along ∼−41°W) and early autumn (∼42–53°N along ∼−41°W) as part of the North Atlantic Aerosols and Marine Ecosystems Study (NAAMES). We estimate that 4–35% of seasonal NCP is partitioned as ΔDOC and that annual vertical DOC export ranges between 0.34 and 1.15 mol C m–2 in the temperate and subpolar western North Atlantic. Two lines of evidence reveal that non-siliceous picophytoplankton, like Prochlorococcus, are indicator species of the conditions that control the accumulation of DOC and the partitioning of NCP as ΔDOC.

Amala Udayakumar, Tamilapur Maharudrappa Shivalingaswamy

The small carpenter bee, Ceratina binghami (Xylocopinae:Apidae) is an important pollinator of many agricultural and horticultural crops. The nests constructed by the bee in the pruned pithy stems of Caesalpinia pulcherrima were collected to study its biology under laboratory conditions. The bee constructs its nest in the pithy stems of different plants by chewing over the pith layer. The bee is oligolectic in habit and make pollen balls and provision its broods in the cells with an interesting guarding behavior in the nest. The nests consisted of egg, larvae, prepupae, pupae and adult stages. Life cycle of the bee was completed in 41.67±3.12 days. Pupal stage consisted of different colors of eye pigmentation. Foraging activity of the bee started during morning hours approximately between 6.45 to 7.15 am and ended during the late evening hours of 4.50 to 5.15 pm. The nest architecture of the bee was studied and presented. The nesting behavior and short life cycle of C. binghami in pithy stems of C. pulcherrima helps in the in-situ conservation and utilization of the bee species in the pollination of agricultural crops.

Ian A. Morelan, Christopher A. Gaulke, Thomas J. Sharpton et al.

Many cnidarians form symbiotic relationships with brown dinoflagellate algae in the genus Symbiodinium. Bacteria are important to this symbiosis, with diverse functions such as providing nutrients to the symbiont and pathogen protection to the cnidarian. Disrupted bacterial communities are associated with thermally stressed cnidarians, which have a higher likelihood of expelling their symbionts, an event called bleaching. To better understand the association between thermal tolerance and bacterial community structure, we studied communities associated with an exceptionally thermal tolerant cnidarian, Anthopleura elegantissima. This intertidal symbiotic sea anemone is distributed from the subtropical waters of Baja California to subarctic Alaska, and experiences daily temperature fluctuations of up to 20°C. It is also flexible in its symbioses, predominantly hosting Symbiodinium, but occasionally hosting the green algae Elliptochloris marina or existing without symbionts in an aposymbiotic state. We used 16S rRNA gene amplicon sequencing to characterize the natural variation of microbial communities associated with Anthopleura elegantissima in these three symbiotic states and across a latitudinal gradient. In this study, we identified a core microbiome, made up predominantly of low-abundance taxa. We found that the communities associated with A. elegantissima were weakly linked to latitude. Diversity analyses revealed significantly higher species richness values for microbial communities associated with anemones hosting E. marina. Lastly the microbiome communities associated with different symbiotic states were compositionally distinct. Taken together, our results suggest that the structure of microbial communities associated with these temperate cnidarians is tightly linked to symbiotic state and weakly linked to other biogeographic phenomena.

Jinmin Lee, Victoria P. Werth, Victoria P. Werth et al.

The 5th Scientific Conference of the International Pemphigus and Pemphigoid Foundation (IPPF), “Pemphigus and Pemphigoid: A New Era of Clinical and Translational Science” was held in Orlando, Florida, on May 15–16, 2018. Scientific sessions covered recent, ongoing, and future clinical trials in pemphigus and bullous pemphigoid, disease activity and quality of life instruments, and the IPPF Natural History Study. Furthermore, the meeting provided an opportunity to hear firsthand from patients, investigators, and industry about their experience enrolling for clinical trials.

Marie-Sophie Garcia-Heras, Beatriz Arroyo, François Mougeot et al.

The timing of breeding can strongly influence individual breeding performance and fitness. Seasonal declines in breeding parameters have been often documented in birds, particularly in the Northern Hemisphere. Fewer studies have investigated whether seasonal declines in productivity vary in space, which would have implications for a species’ population dynamics across its distributional range. We report here on variation in the timing of breeding in the Black Harrier (Circus maurus), an endangered and endemic raptor to Southern Africa. We investigated how key breeding parameters (clutch size, nesting success and productivity) varied with the timing of breeding, weather conditions (rainfall and temperature) and between contrasted regions (coastal vs. interior-mountain). Black Harrier onset of breeding extended over an 8-month period, with a peak of laying between mid-August and end of September. We show a marked seasonal decline in all breeding parameters. Importantly, for clutch size and productivity these seasonal declines differed regionally, being more pronounced in interior-mountain than in coastal regions, where the breeding season was overall shorter. Timing of breeding, clutch size and productivity were also partly explained by weather conditions. In coastal regions, where environmental conditions, in particular rainfall, appear to be less variable, the timing of breeding matters less for breeding output than in interior-mountain regions, and breeding attempts thus occurred over a longer period. The former areas may act as population sources and be key in protecting the long-term population viability of this threatened endemic raptor. This study provides unique evidence for a regionally variable seasonal decline in breeding performance with implications for population biology and conservation.

Emilia del Valle Silva, Ricardo Alonso

Heinrich Max Sparn (1889-1966) castellanizó su nombre alemán por el de Enrique Sparn, con el cual firmó su obra bibliográfica en la Argentina. Desde 1918 hasta 1954 se desempeñó en la Academia Nacional de Ciencias de Córdoba (ANCC) donde tuvo una extensa carrera como bibliotecario, secretario y miembro de pleno derecho de la Academia. Asimismo fue miembro del Instituto de Bibliografía Regional del Departamento de Filosofía de la Universidad de Buenos Aires y Jefe de la Comisión de Coordinación de todas las bibliotecas de la Universidad de Córdoba. No solo fue un gran bibliotecario sino que además se destacó como bibliógrafo científico, llevando a cabo minuciosas investigaciones sobre los temas importantes de la época los que le permitieron realizar contribuciones científicas con aportes estadísticos, sociológicos, culturales y educativos. Se destacó por haber compilado abundante literatura de los siglos XIX y XX, especialmente sobre geología, mineralogía, paleontología, ciencias naturales e historia de las ciencias.  Sus publicaciones suman un centenar de trabajos especialmente en actas, boletines y misceláneas de la ANCC. Se lo propone en este trabajo como el padre de la bibliografía científica argentina.

David J. Nachón, Sandra Barca, María J. Servia

Evaluation of fecundity is a key step to quantify the reproductive potential of individual fish and to understand the stock-recruitment relationship, increasing the knowledge of the state of a stock and improving the assessment of the spawning stock biomass. For the present work we investigated the fecundity and gonad development in anadromous female twaite shad, Alosa fallax (Lacépède, 1803), during the upstream spawning migration in the River Ulla. Thirty-four females were sampled with trammel nets between April and June 2011 in seating areas for this species, located at 24 km and 20 km from the Atlantic Ocean respectively. Fish were lengthed to the nearest millimetre, weighed to the nearest gram and aged by using scales. Factor condition (K) was estimated as K= (TW/TL^3)*100 where TW is fish total weight (g) and TL is fish total length (cm). The ovaries from each female were removed and weighted to the nearest 0.01 gram. Approximately one gram samples were taken from the anterior, central and posterior regions of each ovary and preserved in 70 % ethanol. The number of eggs in each subsample was counted and the fecundity computed from the mean. Individual fecundity (F) was computed and F was divided by the weight of the fish to estimate relative fecundity (FR). Also the gonadosomatic index (GSI) was calculated to assess changes in fish maturity and spawning stage during the upstream migration. Female age ranged from 4 to 7 years and values of TL, TW, K and GSI were [mean ± SE (range)]: 493 ± 7.3 mm (408-562 mm); 1,112 ± 53.7 g (592-1,626 g); 0.91 ± 0.02 (0.67-1.09) and 12.5 ± 0.47 (6.6-21.4) respectively. The value of fecundity (F) was [mean ± SE (range)]: 96,471 ± 6,493 oocytes (24,962 to 182,154 oocytes), while the relative fecundity (Fr) was [mean ± SE (range)]: 87,142 ± 3,592 oocytes (25,319 to 129,189 oocytes). A significant correlation (Spearman´s ρ test, p<0.05) between fecundity and all parameters has been determined. As observed in previous studies variables that best correlated with fecundity were the TW (correlation coefficient: 0.793), K (correlation coefficient: 0.640) and TL (correlation coefficient: 0.612).

Yong yue Lu

While antenna is the main organ for insect to accept the external chemical signals, the antennal sensilla that are diverse in structure and function form the insect receptors in chemical communication. Since a variety of Pseudacteon species are important natural enemies of the red imported fire ant, Solenopsis invicta Buren (. invicta), to elucidate the types of Pseudacteon sensilla will promote the study and understanding of the selection behavior of Pseudacteon in parasitizing . invicta. This study has used scanning electron microscope (SEM) to observe and investigate the female’s antennal sensilla of three Pseudacteon species, the Pseudacteon (P.) litoralis, P. obtusus, and P. tricuspis, and demonstrated that there are four types of sensilla, the trichoid, basiconic, coeloconic, and chaetic sensilla, on their antennal flagellum. Among them, the former three are common in all three species, with trichoid sensillum as mostly abundant, while the chaetic sensillum exists only in the antennae of P. obtusus. The trichoid sensilla exhibit significant interspecies variations and are further classified into two subtypes based on the presence or absence of protrusions, the surface of which contains different shades of groove-like or irregular punctate structures. The basiconic sensilla resemble short spines with densely porous structures on the surface and are in the length of 7.3-9.8 μm and the width of 1.3-1.6 μm, upright or slightly bent. The coeloconic sensilla are irregularly formed in the middle and base of the flagellum, without surface pores; each coeloconic sensillum has eight finger-like folds in unequal lengths, while the end of the fold resembles a blunt cone. The chaetic sensilla enlarge at the base, possess multiple fold-like structures and fine-tipped ends, and are approximately 5 μm in length.