Abundance, distribution, and associated forage losses of pest grasshoppers (Orthoptera: Acrididae) in the Argentine Pampas.

The goal of this study was to assess the status of Dichroplus elongatus and Borellia bruneri as actual agricultural pests in the Argentine Pampas by determining their abundance, distribution, and associated forage loss. The study was conducted in Laprida and Tandil, two counties in Buenos Aires province. In each county 20 sampling sites were established and monitored from 2012 to 2018. B. bruneri was more abundant and with a wider distribution in Laprida (91.4% of the sites) than in Tandil (42.1% of the sites) while D. elongatus abundance was significantly higher from 2012 to 2016 in Tandil than in Laprida and its distribution was wide in Laprida (75% of the sites) and very wide in Tandil (77.14%). Under field-cage conditions forage loss caused at three different densities (8, 16, and 32 ind/m2) of D. elongatus and B. bruneri adults on a pasture of Festuca arundinacea was estimated. Forage loss caused by D. elongatus was significantly higher than that caused by B. bruneri. Dichroplus elongatus caused a significant decrease in biomass at the three densities respect to the control, while B. bruneri only caused a significant decrease at the highest density. Our study suggests that although the gomphocerine B. bruneri is an abundant and widely-distributed species capable of doing some damage in the grasslands of the southern Pampas, it is comparatively much less harmful than the melanopline D. elongatus.

Addressing Health Inequities in the United States: A Case Report on Autism Spectrum Disorder (ASD) and Social Determinants of Health.

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder that presents with delays in developmental milestones, social impairment, and behavioral difficulties. Treatment relies upon an intensive individualized multidisciplinary medical and therapeutic approach. This case presents a child affected by ASD and other associated conditions, whose care was significantly limited by the effects of social determinants of health, including lack of transportation, housing instability, low income, and most importantly, lack of health insurance. Without universal health coverage, the US healthcare system requires that patients have insurance or pay out-of-pocket to access medical care. It is vital that healthcare providers are able to recognize and address these barriers in order to help pediatric patients and their families navigate a difficult and often inequitable healthcare system. It is also crucial to emphasize the importance of healthcare providers, policymakers, and advocacy organizations to work together to address the systemic barriers that limit access to quality care for children with ASD.

Detection of Apicystis bombi (Apicomplexa: Neogregarinorida) in carpenter bees of Argentina.

Historically, the neogregarine Apicystis bombi was isolated almost exclusively from bumble bees (Bombus spp.) where it disrupts adipose tissue, increasing hosts' mortality rates. Records in solitary bees are scarce worldwide. To check for its presence in carpenter bees (genus Xylocopa), campaigns were performed in Argentina capturing 154 individuals of five species (X. augusti, X. splendidula, X. atamisquensis, X. frontalis, X. nigrocincta). The presence of A. bombi was detected by molecular means in X. augusti, X. atamisquensis, and X. nigrocincta in four of the nine provinces screened. The pathogenesis and eventual impact that A. bombi may cause in individuals or populations of Xylocopa species remain unknown. The presence of A. bombi in northern Argentina would be contradictory to the hypothesis that its occurrence is the exclusive result of its introduction to South America through invasive, infected exotic bumble bees.

Relationships and taxonomy of the genus Diponthus Stl (Orthoptera: Acridoidea: Romaleidae).

Diponthus Stl, one of the most diversified and widely distributed Romaleinae genera, is endemic to southern South America. This colorful grasshopper genus is placed within Romaleini and currently includes 16 valid species from a total of 22 nominal ones, most of them only known from their original descriptions. The aims of this study were to propose a morphology-based phylogenetic hypothesis of relationships among the species of Diponthus, and to conduct a taxonomic revision, including the description of four previously unknown species. Parsimony analysis of 79 morphological characters strongly recovered the monophyly of genus Diponthus, and Gurneyacris as its sister group. Internal clades within Diponthus were supported by external morphology and coloration patterns, while characters from male genitalia were shown to be more useful for species differentiation. Based on the results of the taxonomic review, Diponthus is constituted by 16 valid species, with the following nomenclatural changes proposed: Diponthus nigroconspersus (Stl) is considered a valid name; D. invidus Carl and D. bilineatus Rehn are synonymized under D. virgatus (Gerstaecker); Diponthus clarazianus Pictet & Saussure is synonymized under D. cribratus (Serville); D. paulista Rehn is synonymized under D. porphyreus (Gerstaecker); D. maculiferus (Walker) is synonymized under D. electus (Serville). New names are proposed for four undescribed species from Bolivia (D. colorbellus sp. nov. and D. dilatatus sp. nov.), Argentina (D. paranaensis sp. nov.) and Brazil (D. salvadorii sp. nov.).

Intelligent Design Optimization System for Additively Manufactured Flow Channels Based on Fluid-Structure Interaction.

Based on expert system theory and fluid-structure interaction (FSI), this paper suggests an intelligent design optimization system to derive the optimal shape of both the fluid and solid domain of flow channels. A parametric modeling scheme of flow channels is developed by design for additive manufacturing (DfAM). By changing design parameters, a series of flow channel models can be obtained. According to the design characteristics, the system can intelligently allocate suitable computational models to compute the flow field of a specific model. The pressure-based normal stress is abstracted from the results and transmitted to the solid region by the fluid-structure (FS) interface to analyze the strength of the structure. The design space is obtained by investigating the simulation results with the metamodeling method, which is further applied for pursuing design objectives under constraints. Finally, the improved design is derived by gradient-based optimization. This system can improve the accuracy of the FSI simulation and the efficiency of the optimization process. The design optimization of a flow channel in a simplified hydraulic manifold is applied as the case study to validate the feasibility of the proposed system.

Infectivity of Paranosema locustae (Microsporidia) against gregarious-phase South American locust (Orthoptera) when treated en masse.

En masse inoculations with Paranosema locustae, an intracellular parasite of adipose tissue of grasshoppers and locusts and the only microsporidium registered as a biocontrol agent, were conducted against crowded fourth-instar nymphs of the South American locust Schistocerca cancellata and the grasshoppers Dichroplus schulzi and Ronderosia bergii. Infection did not develop in the locust, but was highly prevalent in the two grasshopper species. We hypothesize that absolute absence of infection in S. cancellata may constitute a case of density-dependent prophylactic resistance, an elevation of the baseline immunity of an organism in order to cope with disease that is prevalent in species exhibiting phase polyphenism.

Beauveria bassiana (Ascomycota: Hypocreales) Introduced as an Endophyte in Corn Plants and Its Effects on Consumption, Reproductive Capacity, and Food Preference of Dichroplus maculipennis (Orthoptera: Acrididae: Melanoplinae).

In this study, the effects of strain Beauveria bassiana (LPSC 1067) as an endophyte in corn plants on consumption, fecundity, and food preference of Dichroplus maculipennis were examined. We observed that the daily consumption by grasshoppers fed with control plants was almost twice that of those that were fed treated plants. Significant differences in fecundity of grasshoppers that were fed with treated plants compared with those that only fed on control plants were also observed. The number of eggs laid per female fed with control plants was 27.2, while the number of eggs laid per female that were fed during 15 d with treated plants was 17.7. Similar results were observed when the number of embryonated eggs was evaluated. The highest number of embryonated eggs were recorded in those females that only fed on control plants (96%) while fewer embryonated eggs were recorded in grasshoppers fed for 15 d with treated plants only (25%). In relation to food preference the average consumption rate for D. maculipennis females on control corn plants was 303.8 ± 24.5 mg while it was only 25 ± 2.1 mg on plants treated with B. bassiana as an endophyte. In summary, we observed that B. bassiana as a corn plant endophyte negatively affected the daily consumption rate, fecundity and food preference of D. maculipennis.

Long-term prevalence of the protists Crithidia bombi and Apicystis bombi and detection of the microsporidium Nosema bombi in invasive bumble bees.

An initial survey in 2009 carried out at a site in northwestern Patagonia region, Argentina, revealed for the first time in South America the presence of the flagellate Crithidia bombi and the neogregarine Apicystis bombi, two pathogens associated with the Palaearctic invasive bumble bee Bombus terrestris. In order to determine the long-term persistence and dynamics of this microparasite complex, four additional collections at the same site (San Carlos de Bariloche) were conducted along the following seven years. Both protists were detected in all collections: prevalence was 2%-21.6% for C. bombi and 1.2%-14% for A. bombi. In addition, the microsporidium Nosema bombi was recorded for the first time in the country in the last two collections, at prevalences of 12.4% and 2.4% and unusually high infection intensities (Average = 6.56 × 107 spores per individual). Due to the exceptional dispersal ability of the exotic B. terrestris, these three multihost pathogens should be considered as potential threats to South American native bumble bees.

Tubulinosema pampeana sp. n. (Microsporidia, Tubulinosematidae), a pathogen of the South American bumble bee Bombus atratus.

An undescribed microsporidium was detected and isolated from the South American bumble bee Bombus atratus collected in the Pampas region of Argentina. Infection intensity in workers averaged 8.2 × 10(7)spores/bee. The main site of infection was adipose tissue where hypertrophy of adipocytes resulted in cyst-like body formation. Mature spores were ovoid and monomorphic. They measured 4.00 µm × 2.37 µm (fresh) or 3.98 µm × 1.88 µm (fixed). All stages were diplokariotic and developed in direct contact with host cytoplasm. Isofilar polar filament was arranged in 16 coils in one or, posteriorly, two layers. Coiling angle was variable, between perpendicular and almost parallel to major spore axis. Late meronts and sporogonial stages were surrounded by vesicles of approximately 60 nm in diameter. Based on both new and already designed primers, a 1827 bp (SSUrRNA, ITS, LSUrRNA) sequence was obtained. Data analyses suggest that this microsporidium is a new species of the genus Tubulinosema. The name Tubulinosema pampeana sp. n. is proposed.

The invasion of southern South America by imported bumblebees and associated parasites.

The Palaearctic Bombus ruderatus (in 1982/1983) and Bombus terrestris (1998) have both been introduced into South America (Chile) for pollination purposes. We here report on the results of sampling campaigns in 2004, and 2010-2012 showing that both species have established and massively expanded their range. Bombus terrestris, in particular, has spread by some 200 km year(-1) and had reached the Atlantic coast in Argentina by the end of 2011. Both species, and especially B. terrestris, are infected by protozoan parasites that seem to spread along with the imported hosts and spillover to native species. Genetic analyses by polymorphic microsatellite loci suggest that the host population of B. terrestris is genetically diverse, as expected from a large invading founder population, and structured through isolation by distance. Genetically, the populations of the trypanosomatid parasite, Crithidia bombi, sampled in 2004 are less diverse, and distinct from the ones sampled later. Current C. bombi populations are highly heterozygous and also structured through isolation by distance correlating with the genetic distances of B. terrestris, suggesting the latter's expansion to be a main structuring factor for the parasite. Remarkably, wherever B. terrestris spreads, the native Bombus dahlbomii disappears although the reasons remain unclear. Our ecological and genetic data suggest a major invasion event that is currently unfolding in southern South America with disastrous consequences for the native bumblebee species.

Genetic variability of the neogregarine Apicystis bombi, an etiological agent of an emergent bumblebee disease.

The worldwide spread of diseases is considered a major threat to biodiversity and a possible driver of the decline of pollinator populations, particularly when novel species or strains of parasites emerge. Previous studies have suggested that populations of introduced European honeybee (Apis mellifera) and bumblebee species (Bombus terrestris and Bombus ruderatus) in Argentina share the neogregarine parasite Apicystis bombi with the native bumblebee (Bombus dahlbomii). In this study we investigated whether A. bombi is acting as an emergent parasite in the non-native populations. Specifically, we asked whether A. bombi, recently identified in Argentina, was introduced by European, non-native bees. Using ITS1 and ITS2 to assess the parasite's intraspecific genetic variation in bees from Argentina and Europe, we found a largely unstructured parasite population, with only 15% of the genetic variation being explained by geographic location. The most abundant haplotype in Argentina (found in all 9 specimens of non-native species) was identical to the most abundant haplotype in Europe (found in 6 out of 8 specimens). Similarly, there was no evidence of structuring by host species, with this factor explaining only 17% of the genetic variation. Interestingly, parasites in native Bombus ephippiatus from Mexico were genetically distant from the Argentine and European samples, suggesting that sufficient variability does exist in the ITS region to identify continent-level genetic structure in the parasite. Thus, the data suggest that A. bombi from Argentina and Europe share a common, relatively recent origin. Although our data did not provide information on the direction of transfer, the absence of genetic structure across space and host species suggests that A. bombi may be acting as an emergent infectious disease across bee taxa and continents.

Effectiveness of cough etiquette maneuvers in disrupting the chain of transmission of infectious respiratory diseases.

BACKGROUND: The effectiveness of recommended measures, such as "cover your mouth when coughing", in disrupting the chain of transmission of infectious respiratory diseases (IRD) has been questioned. The objective of the current study was to determine the effectiveness of simple primary respiratory hygiene/cough etiquette maneuvers in blocking droplets expelled as aerosol during coughing. METHOD: In this study, 31 healthy non-smokers performed cough etiquette maneuvers in an effort to cover their voluntarily elicited best effort coughs in an open bench format. A laser diffraction system was used to obtain accurate, non-invasive, quantitative, real time measurements of the size and number of droplets emitted during the assessed cough etiquette maneuvers. RESULTS: Recommended cough etiquette maneuvers did not block the release and dispersion of a variety of different diameter droplets to the surrounding environment. Droplets smaller than one-micron size dominate the total number of droplets leaked when practicing assessed maneuvers. CONCLUSIONS: All the assessed cough etiquette maneuvers, performed as recommended, do not block droplets expelled as aerosol when coughing. This aerosol can penetrate profound levels of the respiratory system. Practicing these assessed primary respiratory hygiene/cough etiquette maneuvers would still permit direct, indirect, and/or airborne transmission and spread of IRD, such as influenza and Tuberculosis. All the assessed cough etiquette maneuvers, as recommended, do not fully interrupt the chain of transmission of IRD. This knowledge urges us all to critically review recommended CE and to search for new evidence-based procedures that effectively disrupt the transmission of respiratory pathogens. Interrupting the chain of transmission of IRD will optimize the protection of first responders, paramedics, nurses, and doctors working in triage sites, emergency rooms, intensive care units, and the general public against cough-droplet-spread diseases.

[Diversity and distribution of grasshoppers (Orthoptera: Acridoidea) in grasslands of the Southern Pampas region, Argentina]. / Diversidad y distribución de acridios (Orthoptera: Acridoidea) en pastizales del sur de la región pampeana, Argentina.

In Argentina, the grasslands of Pampas region comprise approximately 15% of the country. As in other grasslands of the world, grasshoppers are among the most important native herbivores. Their economic importance has been recognized in Argentina since the mid to late nineteenth century, since outbreaks of different species have become recurrent phenomena. Therefore, the main objective of this work was to study their diversity and distribution in grasslands of the Southern Pampas region (Laprida county, Buenos Aires province), as one of the most affected areas. The study was conducted during five seasons (2005-10). Sampling sites were represented by the most common plant communities in this area, classified in four categories: native grasslands, disturbed grasslands, implanted pastures and halophilous grasslands. The samplings were conducted from mid-spring to early autumn, with five or six samples per season. We estimated the following population descriptors: species richness (S), eveness (E), dominance (J), and diversity index (H'). In order to evaluate the similitude of the grasshopper communities present in the different plant communities, we used qualitative and quantitative coefficients of similitude. A total of 22 species of grasshoppers were collected, of which 21 belong to the family Acrididae. The subfamily Melanoplinae was the most diverse with eight species. The largest species richness was recorded in native grasslands (18). The different communities of grasshoppers had similar indices of evenness and dominance (p>0.05). Considering all plant communities, the average value of Shannon-Wiener index was 1.58+/-0.075. There was a positive correlation between evenness index and species richness (p<0.05). The diversity index H' was different between plants communities (p<0.05), and it was higher in the disturbed grassland (1.75+/-0.096, p<0.05) than in the halophilous grasslands (1.34+/-0.12). Native and disturbed grasslands had a higher plant richness than halophilous grasslands and implanted pastures (p<0.05). There was a positive relationship between plant richness and grasshoppers species richness, and diversity of grasshoppers. According to the qualitative indices applied, the similitude between different grasshopper communities was higher than 60%. In general, the species that had a higher frequency of occurrence showed greater abundance and distribution. Covasacris pallidinota, Dichroplus elongatus, D. maculipennis, Borellia bruneri and B. pallida were the most widely distributed species, most of them (12) showed a restricted distribution and few (five) an intermediate distribution.

The tracheal mite Locustacarus buchneri in South American native bumble bees (Hymenoptera: Apidae).

As in other regions of the world, bumble bees (Bombus spp.) are important pollinators in the neotropics. Despite its relevance, knowledge on their health is still limited in the region. While external acari are known to occur in these insects, presence of the internal, tracheal mite Locustacarus buchneri is here reported for first time. After the examination of 2,508 individuals of eight Bombus species from Argentina, two workers of Bombus bellicosus and one of Bombus atratus were found parasitized by L. buchneri in localities within San Luis and Buenos Aires provinces, respectively. The rare occurrence recorded agrees with findings from elsewhere in the world.

Spore loads of Paranosema locustae (Microsporidia) in heavily infected grasshoppers (Orthoptera: Acridoidea) of the Argentine Pampas and Patagonia.

Paranosema locustae, an entomopathogen of grasshoppers and locusts, remains the only microsporidium registered as a biocontrol agent. After introductions from North America, it became established in grasshopper communities of Argentina. We measured the infection intensity of field collected, heavily infected male and female adults of individuals belonging to six grasshopper species, five melanoplines (Melanoplinae) (Baeacris pseudopunctulatus, Dichroplus maculipennis, Dichroplus vittatus, Neopedies brunneri, Scotussa lemniscata), and one gomphocerine (Gomphocerinae) (Staurorhectus longicornis). Average spore load among heavily infected grasshoppers ranged from 8.7±0.5×10(7) to 1.1±0.7×10(9). Only females of B. pseudopunctulatus and S. longicornis showed significantly higher spore loads than the males.

Diversidad y distribución de acridios (Orthoptera: Acridoidea) en pastizales del sur de la región pampeana, Argentina / Diversity and distribution of grasshoppers (Orthoptera: Acridoidea) in grasslands of the Southern Pampas region, Argentina

In Argentina, the grasslands of Pampas region comprise approximately 15% of the country. As in other grasslands of the world, grasshoppers are among the most important native herbivores. Their economic importance has been recognized in Argentina since the mid to late nineteenth century, since outbreaks of different species have become recurrent phenomena. Therefore, the main objective of this work was to study their diversity and distribution in grasslands of the Southern Pampas region (Laprida county, Buenos Aires province), as one of the most affected areas. The study was conducted during five seasons (2005-10). Sampling sites were represented by the most common plant communities in this area, classified in four categories: native grasslands, disturbed grasslands, implanted pastures and halophilous grasslands. The samplings were conducted from mid-spring to early autumn, with five or six samples per season. We estimated the following population descriptors: species richness (S), eveness (E), dominance (J), and diversity index (H´). In order to evaluate the similitude of the grasshopper communities present in the different plant communities, we used qualitative and quantitative coefficients of similitude. A total of 22 species of grasshoppers were collected, of which 21 belong to the family Acrididae. The subfamily Melanoplinae was the most diverse with eight species. The largest species richness was recorded in native grasslands (18). The different communities of grasshoppers had similar indices of evenness and dominance (p>0.05). Considering all plant communities, the average value of Shannon-Wiener index was 1.58±0.075. There was a positive correlation between evenness index and species richness (p<0.05). The diversity index H’ was different between plants communities (p<0.05), and it was higher in the disturbed grassland (1.75±0.096, p<0.05) than in the halophilous grasslands (1.34±0.12). Native and disturbed grasslands had a higher plant richness than halophilous grasslands and implanted pastures (p<0.05). There was a positive relationship between plant richness and grasshoppers species richness, and diversity of grasshoppers. According to the qualitative indices applied, the similitude between different grasshopper communities was higher than 60%. In general, the species that had a higher frequency of occurrence showed greater abundance and distribution. Covasacris pallidinota, Dichroplus elongatus, D. maculipennis, Borellia bruneri and B. pallid were the most widely distributed species, most of them (12) showed a restricted distribution and few (five) an intermediate distribution.

Los acridios son componentes nativos de los pastizales, dichos sistemas han sido modificados debido a la intensificación de las actividades agrícola-ganaderas y por lo tanto se considera importante estudiar las comunidades de acridios asociadas. Se estudió la diversidad y distribución de acridios en el Sur de la región pampeana a través de muestreos realizados en las comunidades vegetales más representativas del partido de Laprida, provincia de Buenos Aires, durante cinco temporadas (2005-2010). Se recolectaron 22 especies. La subfamilia Melanoplinae fue la más diversa (ocho especies). La mayor cantidad de especies se observó en los pastizales nativos (18). La diversidad en los pastizales alterados (1.75±0.096) fue superior (p<0.05) a la de los pastizales halófilos (1.34±0.12). La riqueza de plantas en los pastizales nativos y los pastizales alterados fue superior (p<0.05) a la de las demás comunidades. Se registro una relación positiva entre la riqueza de plantas y las variables riqueza y diversidad de acridios. La similitud entre las comunidades de acridios estimada por los índices cualitativos fue superior al 60%. En general, las especies que tuvieron una mayor frecuencia de aparición, mostraron una mayor abundancia y distribución. Covasacris pallidinota, Dichroplus elongatus, D. maculipennis, Borellia bruneri y B. pallida fueron las de mayor distribución, cinco especies tuvieron una distribución intermedia y la mayoría (12) una distribución restringida.

Cough aerosol in healthy participants: fundamental knowledge to optimize droplet-spread infectious respiratory disease management.

BACKGROUND: The Influenza A H1N1 virus can be transmitted via direct, indirect, and airborne route to non-infected subjects when an infected patient coughs, which expels a number of different sized droplets to the surrounding environment as an aerosol. The objective of the current study was to characterize the human cough aerosol pattern with the aim of developing a standard human cough bioaerosol model for Influenza Pandemic control. METHOD: 45 healthy non-smokers participated in the open bench study by giving their best effort cough. A laser diffraction system was used to obtain accurate, time-dependent, quantitative measurements of the size and number of droplets expelled by the cough aerosol. RESULTS: Voluntary coughs generated droplets ranging from 0.1 - 900 microns in size. Droplets of less than one-micron size represent 97% of the total number of measured droplets contained in the cough aerosol. Age, sex, weight, height and corporal mass have no statistically significant effect on the aerosol composition in terms of size and number of droplets. CONCLUSIONS: We have developed a standard human cough aerosol model. We have quantitatively characterized the pattern, size, and number of droplets present in the most important mode of person-to-person transmission of IRD: the cough bioaerosol. Small size droplets (< 1 µm) predominated the total number of droplets expelled when coughing. The cough aerosol is the single source of direct, indirect and/or airborne transmission of respiratory infections like the Influenza A H1N1 virus. STUDY DESIGN: Open bench, Observational, Cough, Aerosol study.

Sphaerularia bombi (Nematoda: Sphaerulariidae) parasitizing Bombus atratus (Hymenoptera: Apidae) in southern South America.

Bumble bees are some of the most important insect pollinators. However, knowledge on parasites associated to bumble bees in South America is very limited. This study reports the first isolation of a sphaerularid nematode parasitizing queens of the native bumble bee Bombus atratus in Argentina. Measurements and morphological characters of eggs, juveniles, and adults strongly suggest that the species is Sphaerularia bombi, a parasite that affects the reproduction and foraging behavior of the host. The nematode was detected in bumble bees of San Carlos de Bariloche, northwestern Patagonia region, and the surroundings of La Plata, northeastern Pampas region. Prevalence varied between 8% and 20%.

Desarrollo post-embrionario, fecundidad y consumo de alimento de Dichroplus exilis (Orthoptera: Acrididae) bajo condiciones controladas

Postembryonic development, fecundity and food consumption of Dichroplus exilis (Orthoptera: Acrididae) under controlled conditions. Dichroplus exilis is a widely distributed species in Southern South America. Although there have been reports of D. exilis as an agricultural pest, some recent observations suggest that the damage attributed to D. elongatus may actually have been caused by D. exilis. This study was conducted to determine the postembryonic life cycle stages, fertility and food consumption of this species under controlled conditions (30°C, 14L-10D, 40% RH).Individuals employed belong to the laboratory-hatched first generation (F1), from adults (n=64, ♀=28, ♂=36) collected in natural grasslands near Rafaela, Santa Fe province in North- Eastern Argentina. Three cohorts of 16, 17 and 20 individuals were monitored independently in acetate tubes on a daily basis, until death of the last insect. Average fecundity was 381.84, 38.54 eggs per female. Egg-pod incubation time was 14.4, 1.08 days and six nymphal instars were recorded. Nymphal development time was 41.38, 0.71 days (I=8.73, 0.20; II=6.38, 0.24; III=5.64, 0.33; IV=7.15; 0.43; V=9.76, 0.54; IV=7.85, 0.95). The recorded food consumption was 9.89, 1.08 (mg/ind/day) for nymphs IV, 18.04, 0.73 (mg/ind/day) for nymphs V-IV, 16.76, 1.06 (mg/ind/day) for pre-reproductive males, 28.09, 1.81 (mg/ind/day) for pre-reproductive females, 7.71, 0.91 (mg/ind/day) for reproductive males and 13.06, 0.71 (mg/ind/day) for reproductive females, while the average adult food consumption, regardless of sex and reproductive status, was 16.41, 4.32mg/day. Average food consumption of adult females was 17.47, 1.15mg, and was significantly higher than that of males (10.83, 0.91mg). Data obtained in this study showed that D. exilis exhibits at least some of the biological attributes needed to configure an actual or potential agricultural pest, albeit not yet recognized as such. Field monitoring ...

La Subfamilia Melanoplinae tiene una relevancia central dentro de la acridiofauna Argentina. Varias especies suelen ser numéricamente dominantes en las comunidades de acridios del país y algunas constituyen serias plagas. El objetivo de este trabajo fue conocer el ciclo de vida postembrionario, la fecundidad y supervivencia de las hembras y el consumo de alimento de Dichruplus exilis bajo condiciones controladas (30°C; 40%HR y 14L-10O). Para ello se realizó el seguimiento de tres cohortes de 16, 17 y 20 individuos. El tiempo de incubación fue de 14.4±1.08 días. La duración del desarrollo ninfal fue 41.38; 0.71 días (I 8.73; 0.20, II 6.38; 0.24, III 5.64; 0.33, IV 7.15; 0.43, V 9.76; 0.54; IV 7.85; 0.95); la fecundidad promedio fue de 381.84, 38.54huevos/hembra. El consumo registrado fue de 9.89; 1.08 (mg/ind./día) para las ninfas de IV, 18.04; 0.73 (mg/ind./día) para las de V y IV, mientras que el consumo promedio de los adultos, sin diferenciar sexo y estado reproductivo, fue de 16.41; 4.32mg/día. Estos parámetros, al ser comparados con los de otras especies afines, indican que D. exilis exhibe atributos biológicos que condicen con los de otros melanoplinos considerados plaga.