Control of invasive Phragmites australis (European common reed) alters macroinvertebrate communities

Wetland restoration often involves invasive plant species suppression to encourage the recovery of native-dominated vegetation communities. However, assessment of recovery is usually focused only on vegetation and the response of other critical wetland biota, such as macroinvertebrates, is seldom assessed. We characterized the aquatic, semi-aquatic, and terrestrial macroinvertebrate communities in remnant, uninvaded marsh to identify restoration targets and compared this to the communities in Phragmites australis-invaded marsh, and in formerly invaded marsh that was treated with the herbicide glyphosate in 2016 to simultaneously evaluate the effects of invasion and of invasive species suppression. We sampled invertebrates in 2017 and 2018 to track two years following herbicide treatment. The invertebrate community composition captured by the emergence traps was similar between P. australis and remnant marsh, suggesting invasion has little effect on macroinvertebrate community structure. There was also high concordance between the aquatic and emerging invertebrate communities in the invaded and uninvaded habitats. In contrast, herbicide-treated sites had a unique community composition, characterized by very high densities of Chironomidae (Diptera) and low taxa richness and evenness. Herbicide-treated sites also exhibited low concordance between the aquatic and emerging invertebrate communities, potentially attributable to the sparse emerging vegetation cover providing limited substrates for emergence. Herbicide-based invasive species control results in considerable changes to the macroinvertebrate community in freshwater marshes for at least two years after treatment, which may have consequences for aquatic food webs and species that rely on macroinvertebrates as prey.

Peridomestic natural breeding sites of Nyssomyia whitmani (Antunes and Coutinho) in an endemic area of tegumentary leishmaniasis in northeastern Argentina

The scarce information about breeding sites of phlebotomines limits our understanding of the epidemiology of tegumentary leishmaniasis. Identifying the breeding sites and seasons of immature stages of these vectors is essential to propose prevention and control strategies different from those targeting the adult stage. Here we identified the rural breeding environments of immature stages of Ny. whitmani, vector species of Leishmania braziliensis in the north of Misiones province, Argentina; then we determined and compared the environmental and structural characteristics of those sites. We also identified the season of greatest emergence and its relationship with adult abundance. During a first collection period, between 28 and 48 emergence traps were set continuously for 16 months in six environments of the farm peridomicile and domicile: below house, chicken shed, experimental chicken shed, forest edge, pigsty and under fruit tree. Traps were checked and rotated every 40 nights. A total of 146 newly emerged individuals were collected (93.8% of them were Ny. whitmani), totaling an effort of 23,040 emergence trap-nights. The most productive environments were chicken shed and below house, and the greatest emergence was recorded in spring and summer. During a second collection period, emergence traps and light traps for adult capture were placed in the chicken shed and below house environments of eight farms. Emergence traps were active continuously during spring, summer, and early autumn. Environmental and structural characteristics of each environment were recorded. A total of 84 newly emerged phlebotomines (92.9% Ny. whitmani; 72,144 emergence trap-nights) and 13,993 adult phlebotomines (147 light trap-nights) were recorded in the chicken shed and below house environments. A positive correlation was also observed between trap success of newly emerged phlebotomines and of adults after 120 days. A high spatial variability was observed in the emergence of Ny. whitmani, with the number of newly emerged individuals being highest in soils of chicken sheds with the highest number of chickens and closest to forest edge. Moreover, below house was found to be as important as chicken sheds as breeding sites of Ny. whitmani. Management of the number of chickens in sheds, soil moisture and pH, and the decision of where to localize the chicken sheds in relation to the houses and the forest edge, might contribute to reduce the risk of human vector exposure and transmission of Leishmania.

Ecological assessment of the lowland relit forest “Bosco delle Sorti della Partecipanza” in Trino (North-Western Italy), applying Diptera Syrphidae as bioindicators

The survey has been realized in the lowland relict forest Bosco delle Sorti della Partecipanza, a site situated in Trino (Piedmont, North-Western Italy), to assess the ecological conservation level of forest habitats using the Syrph the Net methodology. 67 species were recorded, using three Malaise traps, seven Emergence traps and several Net transect in the year 2020. Among these species, 6 are reported for the first time in Piedmont region, 19 are considered decreasing at European level and 2 are threatened in Europe. Forest habitats under scrutiny in the study area are oak-hornbeam mesophilic woodland and alluvial alder lowland. The data analysis allowed to compare observed with expected syrphids for each habitat. At the ecosystem level, the ecological integrity of the forest is moderately negative but the alluvial alder forest macrohabitat can be considered good and overall saproxylic and saprophagous species are particularly well-preserved. The presence of a high number of rare or decreasing species makes Trino wood an important source of biodiversity in Po Plain.

DIVERSITY OF THE BIBIONOMORPHA AND TIPULOMORPHA (DIPTERA) FROM DEAD ASH AND ASPEN WOOD IN THE FORESTS OF LITHUANIA

The aim of this study was to investigate the biodiversity of nematoceran flies associated with dead wood in a forest ecosystem. Although wood is a primary habitat for a vast amount of Diptera species, no effort has previously been made to study saproxylic flies in Lithuania. During this research, emergence traps were used on aspen (Populus tremula) and ash (Fraxinus excelsior) trees in Dūkštų Ąžuolynas forest and Būda Botanical-Zoological Reserve during the period 2014–2019. In total, 672 individuals of the Bibionomorpha and Tipulomorpha collected from fallen tree trunks were identified to species. Seventy-four species represented nine families, with the Sciaridae, Anisopodidae and Mycetophilidae being most abundant. The Sciaridae family has barely studied in Lithuania and its diversity is still poorly known. During the research 23 nematoceran species, of which 19 belonging to the Sciaridae family, are first reported from Lithuania. Key words: nematoceran, saproxylic species, emergence traps.

A study of the biology of Epicharis (Epicharoides) picta using emergence-traps

This study investigates the nesting habits of Epicharis picta in a nest aggregation located in a fragment of the Atlantic forest in Southeastern Brazil. Ten emergence-traps were set up in this nest aggregation to standardize data collection of phenology, natural enemies, and sex ratio. Epicharis picta nests were in an area of 160 m² with a density of 41 nests/m². Nest and cell architecture are described. Epicharis picta is a protandrous, univoltine species with its emergence in this study occurring between 28 January and 15 April. We provide direct evidence of parasitism on E. picta by Rhathymus friesei, Tetraonyx sexguttata and T. aff. lycoides. The predator Apiomerus lanipes was found to prey Epicharis for the first time. We suggest the use of emergence-traps as tools to support studies of ground-nesting bees. In addition, we compile, update, and discuss data on the nesting biology of all Epicharis subgenera.

Production of Culex pipiens in Stormwater and Combined Sewer Catch Basins

ABSTRACT Man-made stormwater and sewage infrastructure, particularly roadside catch basins, provides widespread habitats for immature mosquitoes in urban and suburban environments. Historically, throughout much of the USA, stormwater, sewage, and industrial wastewater were conducted together through “combined” sewer systems, discharging a combination of stormwater and wastewater into streams. Within recent decades, many cities have replaced these combined sewers with “stormwater only” systems that separate stormwater from wastewater. The objective of this research was to evaluate the implications of this infrastructure conversion for production of Culex pipiens, a primary vector for West Nile virus. On a weekly basis over 14 wk, 20 catch basins (10 combined sewer and 10 stormwater only) were sampled for mosquito larvae and emerging adults using the dipping collection method and floating emergence traps. Abundance of larval Cx. pipiens was higher in combined sewer compared with stormwater-only catch basins, while to the contrary, abundance of adult Cx. pipiens was lower in combined sewer compared with stormwater-only catch basins. This study is the first to reveal that habitat attractiveness and quality for Cx. pipiens may vary between combined sewer and stormwater-only catch basins, and our results contribute to a growing body of research to inform vector management and urban planning efforts as municipalities consider the environmental and public health implications of conversion from combined sewage management to separation of stormwater and wastewater.

Distribution of Phlebotomine Sandflies in the Cave Area of Satun Province, Thailand

Leishmaniasis, a sandfly-transmitted protozoan infection, is a neglected health threat in Thailand and the information on its vector is scarce. This study aimed to identify sandfly distribution, abundance, and environmental conditions of natural breeding sites in the cave areas of Satun Province, where previous cases of leishmaniasis were reported. Sandflies were collected during a six-month period using CDC light traps and modified emergence traps. Species distribution, relative abundance, and environmental conditions of potential breeding sites were determined. Our survey of 12,790 sandflies found the highest female abundance in April–May. We identified six known species, the most prevalent being Sergentomyia anodontis. We also found S. barraudi, a potential Leishmania spp. vector, distributing in this area. Most male sandflies had partially rotated genitalia, indicating the breeding site proximity to our trap locations. Potential resting/breeding sites were discovered outside the cave during February–March, and inside during May–June. The environmental parameters showed warm climate, moderate humidity, moderately alkaline pH, moderate-to-high macronutrients, and low-to-high organic matters. In summary, our study provided the spatiotemporal distribution and environmental condition of sandfly potential breeding sites in the cave areas of Satun Province. This data may contribute to more effective vector surveillance programs in the future.

Sampling Considerations for Adult and Immature Culicoides (Diptera: Ceratopogonidae)

Developing sampling programs for Culicoides can be challenging due to variation in ecology and behavior of the numerous species as well as their broad distributions and habitats. In this paper, we emphasize the need to clearly define research goals to select appropriate sampling methods. This includes not just the choice of sampling device, but also choice of attractant, site, number of traps per site, the duration and frequency of sampling, and the number of traps per unit area. Animal-baited trapping using enclosure traps and direct animal aspiration is more labor-intensive but yields information on species attracted to specific hosts as well as their biting rates. Sampling immatures is discussed with respect to choosing collection sites in semiaquatic mud, soil, and rich organic habitats. Sorting and extracting larvae using emergence traps, flotation, and Berlese funnels is also discussed.

Diversity of Trichoptera emergence and their longitudinal distribution along streams in central Palawan, the Philippines

Trichoptera emergences were cumulatively collected from two rivers in central Palawan over 11 months by use of specially modified emergence traps. The quantitative samples were identified at species level. Fifty morphospecies, of which fifteen have been recently newly described, are recognized. The highest species diversity was found in pristine headwater streams. Leptoceridae were most speciose with eleven Oecetis spp., four Leptocerus spp., two Adicella spp., and one species each of Tagalopsyche, Triaenodes, and Triplectides. Highest abundances were observed for Ecnomus cabayugani (Ecnomidae), Dipseudopsis digitata, and Hyalopsyche winkleri (Dipseudopsidae) which contributed alone 34% of the annual emergence. A mid-stream site where mayflies were mainly absent had the highest Trichoptera emergence, brackish water sites the lowest. Many species in Palawan (44% of the taxa) were recorded at a single locality, suggesting that they are stenoecious and that the real number of species on the island might be distinctly higher. This is the first study ever covering quantitative and species-level Trichoptera emergence data for a longitudinal river course.

Preliminary data of the scuttle flies (Diptera: Phoridae) in the linden-oak-hornbeam forest of the Wigry National Park, North East Poland

Faunistic data on 66 species of geophilous scuttle flies cought by emergence traps placed in 6 sites of the linden-oak-hornbeam forest in the Wigry National Park in summer season of 2017 and 2018 are presented. About 60% of the individuals captured each year were species with at least 10 individuals. The same four dominants: Megaselia pulicaria-complex, M. flava, M. abdita and Gymnophora arcuata reached the highest abundance in the compared communities during both study seasons. Species with known biology accounted for only half of the captured species, but among them the most numerous (82%) were species whose larvae were classified as sapro-/necro- and mycophagous.