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We report the first known occurrences of adult Panorpa helena Byers (Mecoptera: Panorpidae) and Rivellia steyskali Namba (Diptera: Platystomatidae) at vertebrate carrion based on recent observations made in Ohio and North Carolina, USA.

Due to Virginia’s geographic location, topographic variability, and diversity of physiographic provinces, the state ranks as one of the most biodiverse areas in the US. Virginia’s myrmecofauna, however, has been insufficiently studied and is not well known. Here we present the first comprehensive list of the ants of Virginia and provide county-level distributions for all taxa. With taxonomic updates taken into account, review of published records revealed that 130 species have been reported from the state. We add another 34 species based on newly collected materials, review of museum and personal collections, and online databases. At present, 164 species and morphospecies, including 15 ant exotics, are known to occur in the state. Another 12 species are provisionally excluded from the list as they represent distribution anomalies, or are based on erroneous records. The work presented here is an initial step towards a more complete treatment of the identification, taxonomy, and natural history of the ant fauna of Virginia.

In 2005, the non-native Nylanderia flavipes was first recorded from Ohio. Here, we present the results of a baseline study designed to assess the status of this exotic species in northeastern Ohio and to explore its potential impacts on local ant communities and the extent to which it has been incorporated into the diet of a native predator, the red-backed salamander. At the sites where N. flavipes occurred, we found a sixfold increase in total ant abundance, with 87% of all ants collected being N. flavipes. The high numerical dominance of N. flavipes did not lead to observable changes in the species richness and abundance of the native ant community. At baits, N. flavipes did not engage in interspecific combat and did not exhibit aggression towards native ants. Thus, aggression and interference competition are not likely factors explaining the high local abundance of N. flavipes. Red-backed salamanders have incorporated N. flavipes into their diet, but further research is needed to understand the interactions of N. flavipes within the forest-floor food web. Although we did not detect changes in the local ant communities in the presence of N. flavipes, we argue that this species’ high local abundance and ability to forage at cooler temperatures may give it a competitive advantage and thereby affect native ants through exploitative competition.

The effects of forest edge on ant species richness and community composition were examined within an urbanized area of northeast Ohio. The ground-dwelling ant fauna was inventoried in three deciduous forest fragments that have resulted from human disturbance. We surveyed ants via leaf-litter extraction along 150 m transects positioned perpendicular to the forest edge. We collected 4,670 individuals from 14 genera and 29 species. Samples closest to the forest edge contained more species and accumulated species at a higher rate than did samples located in the forest interior. Our rarefied and expected richness estimates revealed a decline of species richness from edge to forest interior. The higher ant richness at the forest edge was due mostly to the presence of species characteristic of the neighboring open habitats. Although most of the typical forest ant species were represented equally at the edge and at the forest interior, a few responded to the presence of edges with changes in their relative abundance and frequency of occurrence. Forest edges had a higher proportion of opportunistic species and a lower proportion of cryptic ants, whereas interior locations exhibited a more even distribution among ant functional groups. In addition, we documented a community composition shift between the edge and the forest interior. Consistent with previous findings, we suggest that the edge effects are most pronounced within 25 m of the forest edge, which may have implications for the overall conservation of forest-dwelling fauna.

The benthic invertebrates of three adjacent wetlands in northeastern Ohio, USA were sampled with a benthic corer during May–August 2001. The three wetlands consisted of a deep created wetland that overflowed into a shallow created wetland and a pre-existing natural wetland. The created wetlands were four years old and seeded with cattails. Forty-two invertebrate taxa were collected from all wetlands combined, and 11 taxa were abundant (represented >1% of total). Taxa richness, evenness, and community similarity were comparable among the three wetlands. Seed shrimp (Ostracoda), midges (Diptera: Chironomidae), copepods (Copepoda), fingernail clams (Bivalvia: Sphaeriidae), and water fleas (Cladocera) were the five most abundant taxa (38%, 13%, 11%, 9%, and 8%, respectively). Clams were significantly more abundant in the natural wetland, whereas no significant difference in density of other invertebrates was detected among wetlands. Laboratory inundations of soil taken from the rapidly drying basins of the natural and shallow created wetlands produced 10 taxa that survived the dry periods with desiccation-resistant stages and were dominated by microcrustaceans, Aedes mosquitoes (Diptera: Culicidae), clams, and annelid worms. Our data indicate that the created wetlands developed benthic invertebrate communities that were similar to the adjacent natural wetlands in a short period of time (four years), but clams were slow to colonize the human-made habitats.

BRIDGES is a recurring feature of J-NABS intended to provide a forum for the interchange of ideas and information between basic and applied researchers in benthic science. Articles in this series will focus on topical research areas and linkages between basic and applied aspects of research, monitoring policy, and education. Readers with ideas for topics should contact Associate Editors, Nick Aumen and Marty Gurtz.Forensic entomology has proven to be an important tool in understanding what took place at crime scenes involving human corpses. Traditionally, forensic entomology has focused on terrestrial saprophagous insects, and much less is known about biota colonizing corpses in aquatic environments. In this BRIDGES article, Keiper and Casamatta suggest how knowledge of benthic ecology can be applied to forensic investigations, provide suggestions for future benthic research, and help bridge the gap between benthic science and the applied aspects of forensic sciences.Nick Aumen, nick_aumen@nps.gov...

The sampling efficiency of pitfall traps and Winkler litter extraction in northern deciduous forests was compared using ants. Both techniques are among the most common methods used to measure the diversity of organisms active on the forest floor. During 2005-2006, 90 Winkler and 180 pitfall trap samples from urban forest fragments in northeastern Ohio obtained 9,203 ants representing 31 species. Winklers captured all 31 species, whereas pitfall traps collected a total of 24 species. Winkler samples accumulated species more rapidly than did pitfall traps and had greater total species richness and higher abundance of ants recorded. Consistent with other studies, Winkler sampling was found to catch a greater number of smaller ants, whereas pitfall trapping caught a greater number of large-bodied ants. According to estimates of expected species richness, the combination of the two sampling techniques allowed for the collection of approximately 90% of the ants expected in the surveyed area. Site variation had little effect on the inherent differences in sampling efficacy between the two methods. Either technique adequately collected samples for broad comparisons and documentation of the more typical and representative ant fauna, but Winkler extraction exhibited the advantage of a more complete inventory. The application of both techniques should be considered if the aims of a study require estimation of community properties, such as relative abundance.

Publisher Summary This chapter discusses Diptera, a true flies or two-winged flies that are a group of familiar insects that includes mosquitoes, black flies, midges, fruit flies, and house flies. The Diptera are among the most diverse insect orders, with approximately 150,000 described species. These insects are diverse not only in species richness but also in their structural variety, ecological habits, and economic importance. Diptera have been divided into two or three suborders: Nematocera and Brachycera, with the latter sometimes divided further into the Orthorrhapha and Cyclorrhapha. Although there is general agreement that the Diptera, Brachycera, Cyclorrhapha, and a few other subordinate groups are monophyletic, there is comparably general agreement that the Nematocera is a paraphyletic or grade-level grouping. The dipteran life cycle includes a series of distinct stages or instars. A typical life cycle consists of a brief egg stage, three or four instars, a pupal stage of varying length, and an adult stage that lasts from less than 2 hours to several weeks or even months. Several families of Diptera are of major economic importance and involved in the transmission of more disease pathogens to humans and other animals than any other group of arthropods. Biting flies cause annoyance that impacts tourism, recreation, land development, and industrial and agricultural production, whereas their effects on livestock can cause reduced milk, egg, and meat production.

We present a case report of a 14-month-old girl who ingested a moth cocoon, which resulted in dramatic symptoms of irritability, drooling, and anorexia. Direct laryngoscopy, bronchoscopy, and esophagoscopy under general anesthesia revealed copious, tenaciously adherent, barbed hairs embedded in her tongue and buccal mucosa. Removal of the hairs with irrigation, suction, and brushing was unsuccessful and was eventually abandoned. In the following 48 hours, the girl recovered uneventfully with supportive care. The hairs were subsequently identified as coming from the hickory tussock moth (Lepidoptera: Arctiidae: Lophocampa caryae), which is ubiquitously distributed throughout much of North America. This is the first detailed case report of ingestion of an L caryae cocoon.

Vegetation management for constructed treatment wetlands often involves knocking down emergent vegetation with heavy equipment and inundating the dead vegetation after a period of drying. Such practices create favorable conditions for larval mosquitoes. We studied the relationship between length of the drying period for an emergent macrophyte, Typha sp., and the abundance of aquatic invertebrates in replicated 0.18-m3 wading pools. The mosquito, Culex tarsalis, was significantly more abundant in pools containing vegetation aged for 2 wk before inundation compared to pools containing vegetation aged 5 wk, freshly cut vegetation, or without vegetation. Potential larval mosquito food resources (particles between 2 and 61 microm in equivalent spherical diameter) in the 2-wk aging treatment did not differ significantly from the other treatments during the 5-wk experiment. The abundance of other larval culicids, nonculicine Diptera, and potential mosquito predators (i.e., Dytiscidae and Aeshnidae) did not differ significantly among the vegetation aging treatments.

▪ Abstract Although studies of freshwater entomofauna frequently do not include the biodiversity and ecological roles of higher Diptera, cyclorraphous flies are often numerous and species rich in wetlands. Seventeen families are commonly found in freshwater wetlands, with Ephydridae, Chloropidae, Sciomyzidae, Sphaeroceridae, and Scathophagidae being among the most important in terms of population size and species richness. Difficulty with sampling cryptic larval habitats and species identification challenges may account for the exclusion of acalyptrate and other dipterans from wetlands ecology studies. Large populations are facilitated by the high productivity of freshwater wetlands and the high intrinsic rate of increase characteristic of many species. Higher dipterans exist in all freshwater wetland types, are microhabitat selective, and play significant roles in food webs. The varied strategies for food acquisition and patterns of spatial and temporal distribution limit ecological overlap among the higher Diptera.

Data on colonization of rat carcasses by aquatic insects in riffle and pool areas of a small woodland stream were obtained to elucidate patterns potentially useful for determining the postmortem submersion interval of corpses in flowing water habitats. After 39 days, the carcasses had no visual signs of deterioration in the absence of large scavenging animals. Midge larvae (Diptera: Chironomidae) were the dominant insects colonizing the carcasses. No patterns in numbers of larvae over time were evident, but the diversity of genera increased after 29 days in the riffle. Also, Orthocladius larvae did not begin to colonize the carcasses until after 13 days of submersion in the riffle and after 20 days of submersion in the pool. Although separated only by 20 m, the riffle and pool rats had dissimilar faunal assemblages. This suggests that different indices for determining the postmortem submersion interval of corpses based on midge larvae colonization should be developed for these two habitats. This investigation does not provide replicated data, but does shed light on what may happen to mammalian carcasses placed in a stream at a particular time of the year.