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The complex nature of urban environments can have different effects on species diversity and composition. The aim of this work was to characterize the assemblage of Calliphoridae regarding its richness, abundance, and synanthropy in Córdoba City, Argentina. Three sampling sites differing in their distance to the border of the city and degree of urbanization were selected. In each site, collections were carried out with 12 traps baited with cow liver (200 g per trap) that were operated for five consecutive days during three different times of the year, in April, June and August 2013. A total of 341 adult calliphorids from nine species,, Calliphora vicina Robineau-Desvoidy, Sarconesia chlorogaster (Wiedemann), Chrysomya albiceps (Wiedemann), C. megacephala (Fabricius) and C. chloropyga (Wiedemann) were collected. Lucilia sericata was the most abundant species followed by C. vicina. Species diversity, composition and abundance changed between sites, richness being lowest at the most urbanized site. All species are cosmopolitan except Sarconesia chlorogaster, whose distribution is restricted to South America. These results are consistent with a homogenization of the fauna in urban environments.Key words. Diptera, Calliphoridae, urban landscape, diversity. RESUMENLa complejidad de los entornos urbanos puede tener diferentes efectos en la diversidad y la composición de especies. El objetivo de este trabajo fue caracterizar el conjunto de Calliphoridae en cuanto a su riqueza, abundancia y sinantropía en la ciudad de Córdoba, Argentina. Se seleccionaron tres sitios de muestreo que difieren tanto en la distancia al borde o límite de la ciudad como en la intensidad de la urbanización. En cada sitio se colocaron 12 trampas cebadas con hígado de vaca (200 g por trampa) que permanecieron durante cinco días consecutivos durante tres momentos diferentes del año, en abril, junio y agosto de 2013. Se recolectó un total de 341 califóridas adultos pertenecientes a nueve especies, Lucilia sericata (Meigen), L. eximia (Wiedemann),

Species composition, richness, and relative abundance of the communities of Calliphoridae, Muscidae, and Fanniidae in Córdoba city, Argentina was assessed, and how these characteristics are affected by seasonal and anthropogenic conditions was studied. The study was carried out in thirteen sites with various levels of urbanization during 2014 and 2015, comparing two seasons: the warmer-wet summer and the cold-dry winter. Adult flies were collected in each site using two traps baited with hydrated bone meal. A total of 1683 flies were collected, belonging to twelve genera and 22 species. Several of the species collected are relevant to forensic sciences. The most frequent species were Hydrotaea aenescens (Muscidae) and Fannia fusconotata (Fanniidae). No differences in necrophagous fly richness or relative abundances between the central urban sites and the periphery suburban sites were observed; however, richness was significantly correlated with local (250 m buffer area) built-up density. Species composition differed between the urban and suburban sites. Seasonal differences were also detected: the relative abundances per species were more even in the summer. Dissimilarities in the assemblages were mainly due to differences in the relative abundances of some species, reflecting their adaptability to landscapes with different degree of urbanization. Regardless of season or urbanization density, species richness and effective number of species were higher in traps placed in the sun as opposed to shade. Taken together, these results suggest that in Córdoba city both landscape and local factors explain variations in the necrophagous fly community.

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1. Direct consumption of organic matter by the saprophagous larvae provides the ecosystem with a fundamental service by recycling nutrients and reducing exposure to decomposing matter. The present study aimed to assess the functional role of saprophagous flies in the mass loss of different types of decomposing organic matter.2. Two types of common urban waste were used to measure the role of flies in reducing organic matter: chicken viscera (chicken) and a mixture of flour and uncooked eggs (flour and eggs), representing leftover food. Ten traps baited with each substrate, under field conditions, allowed fly access (exposed to flies) and three traps from each substrate did not (unexposed controls); adult flies entering the traps or emerging from the substrates and substrate mass loss were recorded.3. Species from Calliphoridae, Sarcophagidae, Muscidae, and Fanniidae families were collected mainly in traps baited with chicken, with Phoridae being the most abundant in traps with flour and eggs as bait. A significantly richer (P < 0.05) assemblage of fly species accessed the traps baited with chicken viscera (21 species) compared with those emerging (11 species), whereas similar numbers of species accessed (n = 5) or emerged (n = 1) from traps baited with flour and eggs (average richness accessing 7.97, emerging 2.83). Chicken substrate mass loss and species richness were positively related (r = 0.56, P = 0.001). In traps where richness was larger than 10 species, the substrates were reduced by more than 85% of their initial weight compared with unexposed controls, which lost 30%. Substrate mass loss significantly increased with the abundance of flies (r = 0.73, P < 0.0001).4. The results of the present study support the functional role of saprophagous species diversity on the decomposition rates of organic matter, reinforcing the negative consequences of loss or gain of species in modified landscapes and for ecosystem function.

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The urbanization process affects the structure of insect communities, favouring biotic homogenization processes by promoting adequate conditions for the establishment of synanthropic species. Considering the scarce knowledge about the ecology of Neotropical sarcophagids, we compared the flesh fly community from two different urban zones in two contrasting seasons and examined the response of the Sarcophagidae assemblage to landscape and microhabitat variables. Adult flies were collected in 13 sites with two traps (total number of traps 26) baited with 200 g of hydrated bone meal. A total of 2312 adult sarcophagids were collected belonging to 27 species; Oxysarcodexia paulistanensis (Mattos, 1919) represented >48% of the total sample. The local factor of insolation explained both the abundance and species richness of sarcophagids, collections being higher and richer in traps exposed to sunlight compared with traps placed in the shade regardless of the season. Richness was also affected by the environment, being higher in traps exposed in suburban rather than urban sites. The combination of these factors (sub‐urban environment and availability of open areas) could explain the Sarcophagidae assemblage. The average number of sarcophagid species collected was related to the season, providing a good opportunity to assess the temporal variability of this family in the region.

Abundance of sarcosaprophagous Calyptratae species was monitored by using baited traps and active captures with hand net. Analysis of field data collected in three protected areas in the Valdivian temperate forest of South America (Lanín National Park, Lago Puelo National Park, and Los Alerces National Park) indicated that bottle traps baited with putrescine is a reliable method to estimate local abundance of sarcosaprophagous species by comparison to the active capture method. Also, we describe and compare general patterns of sex bias for four dominant species: Sarconesia magellanica (Le Guillou), Calliphora vicina Robineau-Desvoidy, Microcerella spinigena (Rondani), and Oxysarcodexia varia (Walker). From these analyses, it can be concluded that abundance fluctuations of flies showed significant relationship between the sampling methods. This study showed that besides the expected interspecific differences in trapping efficiency, there are acute intraspecific differences of sex ratios between sampling methods.