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Study of all flies (Diptera) collected for one year from a four-hectare (150 x 266 meter) patch of cloud forest at 1,600 meters above sea level at Zurquí de Moravia, San José Province, Costa Rica (hereafter referred to as Zurquí), revealed an astounding 4,332 species. This amounts to more than half the number of named species of flies for all of Central America. Specimens were collected with two Malaise traps running continuously and with a wide array of supplementary collecting methods for three days of each month. All morphospecies from all 73 families recorded were fully curated by technicians before submission to an international team of 59 taxonomic experts for identification.        Overall, a Malaise trap on the forest edge captured 1,988 species or 51% of all collected dipteran taxa (other than of Phoridae, subsampled only from this and one other Malaise trap). A Malaise trap in the forest sampled 906 species. Of other sampling methods, the combination of four other Malaise traps and an intercept trap, aerial/hand collecting, 10 emergence traps, and four CDC light traps added the greatest number of species to our inventory. This complement of sampling methods was an effective combination for retrieving substantial numbers of species of Diptera. Comparison of select sampling methods (considering 3,487 species of non-phorid Diptera) provided further details regarding how many species were sampled by various methods.        Comparison of species numbers from each of two permanent Malaise traps from Zurquí with those of single Malaise traps at each of Tapantí and Las Alturas, 40 and 180 km distant from Zurquí respectively, suggested significant species turnover. Comparison of the greater number of species collected in all traps from Zurquí did not markedly change the degree of similarity between the three sites, although the actual number of species shared did increase.        Comparisons of the total number of named and unnamed species of Diptera from four hectares at Zurquí is equivalent to 51% of all flies named from Central America, greater than all the named fly fauna of Colombia, equivalent to 14% of named Neotropical species and equal to about 2.7% of all named Diptera worldwide. Clearly the number of species of Diptera in tropical regions has been severely underestimated and the actual number may surpass the number of species of Coleoptera.        Various published extrapolations from limited data to estimate total numbers of species of larger taxonomic categories (e.g., Hexapoda, Arthropoda, Eukaryota, etc.) are highly questionable, and certainly will remain uncertain until we have more exhaustive surveys of all and diverse taxa (like Diptera) from multiple tropical sites.        Morphological characterization of species in inventories provides identifications placed in the context of taxonomy, phylogeny, form, and ecology. DNA barcoding species is a valuable tool to estimate species numbers but used alone fails to provide a broader context for the species identified.

The obligate anuran myiasis blow fly Lucilia bufonivora Moniez is reported from North America for the first time. The L. bufonivora species group is defined on the basis of the aedeagus and the history and biology of the North American species (L. bufonivora, L. elongata Shannon and L. silvarum (Meigen)) are discussed. A key is provided to separate the three North American species of this group. The North American species L. thatuna Shannon, a member of the L. sericata (Meigen) species group, is also treated because it is likely a parasite of anurans and is poorly known. The male abdominal sternites, aedeagus (L. elongata only), pregonites, postgonites, bacilliform sclerites, ejaculatory sclerites, and female ovipositors and spermathecae of L. elongata and L. thatuna are illustrated for the first time.

A key to 23 species of Neotropical Lucilia, including six new species is given. Information is provided on all known Lucilia species found in the region, including the West Indies, Galápagos Islands, and Central and South America. The following six new species are described based on the examination of over 2700 adult specimens from Central and South America: Lucilia albofusca sp. nov. from southern Central America and northern South America, Lucilia nitida sp. nov. from Brazil, Peru and Venezuela, Lucilia pulverulenta sp. nov. from Central America (Honduras south to Panama) and South America (Colombia and Ecuador), Lucilia rognesi sp. nov. from Costa Rica, Honduras and Panama, Lucilia vulgata sp. nov. from South America (widespread from Venezuela to Argentina), and Lucilia woodi sp. nov. from Central America (Honduras south to Panama). The status of Phaenicia japuhybensis Mello, 1961 is clarified; it is considered a valid species of Lucilia. Musca ochricornis Wiedemann, 1830 is removed from its current synonymy with Musca eximia Wiedemann, 1819 and considered a valid species of Lucilia. Lucilia mera Shannon & Del Ponte, 1926 and L. primaveris Shannon & Del Ponte, 1926 are synonymized with L. ochricornis, syn. nov. Lucilia littoralis Blanchard 1938 is synonymized with L. eximia (Wiedemann, 1819), syn. nov. Lectotypes are designated for L. mera, L. primaveris, and L. ochricornis.

In DNA barcoding, a short standardized DNA sequence is used to assign unknown individuals to species and aid in the discovery of new species. A fragment of the mitochondrial gene cytochrome c oxidase subunit 1 is emerging as the standard barcode region for animals. However, patterns of mitochondrial variability can be confounded by the spread of maternally transmitted bacteria that cosegregate with mitochondria. Here, we investigated the performance of barcoding in a sample comprising 12 species of the blow fly genus Protocalliphora, known to be infected with the endosymbiotic bacteria Wolbachia. We found that the barcoding approach showed very limited success: assignment of unknown individuals to species is impossible for 60% of the species, while using the technique to identify new species would underestimate the species number in the genus by 75%. This very low success of the barcoding approach is due to the non-monophyly of many of the species at the mitochondrial level. We even observed individuals from four different species with identical barcodes, which is, to our knowledge, the most extensive case of mtDNA haplotype sharing yet described. The pattern of Wolbachia infection strongly suggests that the lack of within-species monophyly results from introgressive hybridization associated with Wolbachia infection. Given that Wolbachia is known to infect between 15 and 75% of insect species, we conclude that identification at the species level based on mitochondrial sequence might not be possible for many insects. However, given that Wolbachia-associated mtDNA introgression is probably limited to very closely related species, identification at the genus level should remain possible.

Wolbachia are widespread cytoplasmically inherited bacteria that induce various reproductive alterations in host arthropods, including cytoplasmic incompatibility (CI), an incompatibility between sperm and egg that typically results in embryonic death. CI has been invoked as a possible mechanism for reproductive isolation and speciation in arthropods, by restricting gene flow and promoting maintenance (and evolution) of genetic divergence between populations. Here we investigate patterns of Wolbachia infection and nuclear and mitochondrial differentiation in geographical populations of the birdnest blowfly Protocalliphora sialia. Blowflies in western North America are infected with two A-group Wolbachia, with some individuals singly and others doubly infected. Individuals in eastern North America mostly show single infections with a B-group Wolbachia. Populations in the Midwest are polymorphic for infections and show A- or B-group infection. There is a low level of mitochondrial divergence and perfect concordance of mitochondrial haplotype with infection type, suggesting that two Wolbachia-associated selective sweeps of the mitochondrion have occurred in this species. Amplified fragment length polymorphism analysis of nuclear genetic variation shows genetic differentiation between the eastern-Midwestern and western populations. Both Midwestern and eastern flies infected with A-Wolbachia show eastern nuclear genetic profiles. Current results therefore suggest that Wolbachia has not acted as a major barrier to gene flow between western and eastern-Midwestern populations, although some genetic differentiation between A-Wolbachia infected and B-Wolbachia infected individuals in eastern-Midwestern populations cannot be ruled out.

We described the community composition of the ectoparasitic flies Protocalliphora Hough (Diptera: Calliphoridae) and their Nasonia (Ashmead) (Hymenoptera: Pteromalidae) parasitoids collected from tree swallow, Tachycineta bicolor (Vieillot), nests in southern Québec, Canada, in 2008 and 2009. The prevalence of nest infestation by ProtocaUiphora was 70.8% in 2008 and 34.6% in 2009. The average parasitic burden of Protocalliphora spp. was estimated at 5.53 (±5.61 SD) pupae per nestling for 2008 and 4.66 (±9.31 SD) pupae per nestling for 2009. The percentage of nests containing ProtocaUiphora pupae parasitized by Nasonia spp. was of 85.3% in 2008 and 67.2% in 2009. Three species of Protocalliphora were collected--Protocalliphora sialia Shannon & Dobroscky, Protocalliphora bennetti Whitworth, and Protocalliphora metallica (Townsend)--and two species of Nasonia, Nasonia vitripennis (Walker) and Nasonia giraulti Darling. This is the first record of P. bennetti and N. giraulti in the province of Québec. Our findings provide further evidence for observation made previously that altricial bird nests are more frequently and more heavily infested by blow flies in western than in eastern North America. Our data also suggest that more than a quarter of the tree swallow within the study area are exposed to high levels of ectoparasitism that could negatively affect their health. [ABSTRACT FROM AUTHOR]