Evaluation of environmental and local factors on urban sarcosaprophagous Diptera: a case study with Sarcophagidae.

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.

A Rare Case of Pseudomyiasis in a Dog by Hermetia illucens (Diptera: Stratiomyidae).

Hermetia illucens (L.) (Diptera: Stratiomyidae), commonly known as black soldier fly is a dipterous species which can produce enteric pseudomyiasis in humans and domestic animals. Veterinary cases of intestinal myiasis caused by H. illucens in dogs have not been reported previously. We present this rare pseudomyiasis (= accidental myiasis) produced by infestation with several larvae of the intestinal tract in a dog inhabiting a city in the province of Buenos Aires, Argentina.

Sex Ratio and Abundance Fluctuations of Sarcosaprophagous Calyptratae (Diptera): Field Evaluation of Two Sampling Techniques.

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.

Two New Species of Oxysarcodexia Townsend (Diptera: Sarcophagidae) From the Chaco Forest Ecoregion of South America.

Two new Neotropical species of the genus Oxysarcodexia Townsend (Diptera: Sarcophagidae) from Chaco ecoregion of Argentina are described, O. berthet, sp. nov. and O. ibera, sp. nov. Both species were recovered from localities in the eastern part of the Chaco forest (Humid Chaco). The descriptions are based on the male external morphology and terminalia. Photographs and SEM images are provided to aid in the identification of the species.

Assessment of Sampling Methods for Sarcosaprophagous Species and Other Guilds of Calyptratae (Diptera) in Temperate Forests of Southern South America.

The aim of the present study was to compare three different collecting methods, namely, baited traps, active capture with hand net, and Malaise traps, to establish which method is more appropriate for sampling different Calyptratae guilds inhabiting temperate forests of South America. Specifically, it was analyzed which technique or combination of techniques is more adequate for obtaining sarcosaprophagous Calyptratae, which are of great interest from a veterinary and medical viewpoint. Taxa were classified into guilds according to their biology. Active capture was the technique that registered the highest diversity of guilds. When analyzing sarcosaprophagous species, it was observed that their percentage of captures, diversity, and abundance showed clear differences in guild composition between the trapping techniques studied. From these analyses it can be concluded that baited traps and active trapping are complementary methods for capturing sarcosaprophagous Calyptratae species. From the perspective of the biodiversity of this group, the combination of both methodologies allows obtaining a more complete inventory of sarcosaprophagous species of austral temperate forests of South America.

Assessment of the Abundance and Diversity of Calliphoridae and Sarcophagidae (Diptera) in Sites With Different Degrees of Human Impact in the Iberá Wetlands (Argentina).

The aim of the present study was to explore the diversity and describe the spatial distribution of Calliphoridae and Sarcophagidae along an urbanization gradient in the Iberá Wetlands. The flies were collected at 18 sampling points, three per site. In total, 3,318 flies were collected (3,077 blow flies and 241 flesh flies), distributed in 13 genera and 33 species. Calliphoridae was the most abundant, comprised 92.74% of all adult flies. Chrysomya albiceps (Wiedemann), Cochliomyia macellaria (F.), Chrysomya megacephala (F.), and Chrysomya putoria (Wiedemann) were the most abundant species, representing 82.21% of the total sample. The genus Oxysarcodexia Townsend was the most diverse with 10 species represented. The abundance of exotic species represents 62.85% of the total sample, showing a reduction toward less disturbed sites. The results of this study indicated that sites with intermediate impact had higher diversity than those where the disturbances are high or absent. Our findings provide the first assessment of Calliphoridae and Sarcophagidae diversity in the area of the Iberá Wetlands.

Sex-biased Patterns of Saprophagous Calyptratae (Diptera) Collected With Different Baits of Animal Origin.

The aim of the present study was to explore the response behavior of males and females of different families of Calyptratae (Diptera) to two different baits (rotten liver and feces) as separate attractants. We describe the sex bias toward these baits for species of Calliphoridae, Muscidae, and Sarcophagidae and compare the general patterns of this sex bias according to the family or trophic guild. In total, 15 species of Sarcophagidae, 10 species of Muscidae, and 9 species of Calliphoridae were analyzed. A female-biased pattern was observed for most calliphorids and for all muscids, whereas a male-biased pattern was more frequent among sarcophagids. The female captures on each kind of bait were assessed as a potential indicator of potential breeding substrates of the species. Three different trophic guilds and their pattern of sex bias were compared. The results obtained allow hypothesizing on the biological traits of saprophagous species, especially on their potential breeding substrates, and assessing proper sampling methods.

Two species of Microcerella (Diptera: Sarcophagidae) found in highland arid landscapes of Argentina, during forensic studies.

Two species of Microcerella Macquart were obtained from pig and llama corpses during a decomposition field experiment in highlands desert landscapes of Catamarca, Argentina. We sampled four pig and two llama carcasses. Microcerella antofagastensis sp. nov. is described, and M. quimaliensis (Lopes, 1982) is redescribed. Illustrations of male and female terminalia of both species are provided and should allow a correct identification. Notes on the biology of both species are given.

Umbilical myiasis in a human newborn.

The new-world screw-worm fly, Cochliomyia hominivorax, is an obligate ectoparasite of domestic and wild animals, and in some cases may affect humans. Myiasis in the human neonatal period is a rare occurrence and almost exclusively found in neotropic areas. Although umbilical myiasis is well-recognized in animals, infestation of human umbilical cord and abdominal tissue is a rare occurrence. Once the diagnosis has been made, the treatment is usually straightforward and uncomplicated. In this article, a newborn infant from an urban area is reported with umbilical myiasis caused by fly larvae of C. hominivorax. The blowfly causing this infestation belongs to the family Calliphoridae (Diptera) and the genus Cochliomyia that usually infests only open wounds of animals.