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.

Estimations of tropical insect diversity generally suffer from lack of known groups or faunas against which extrapolations can be made, and have seriously underestimated the diversity of some taxa. Here we report the intensive inventory of a four-hectare tropical cloud forest in Costa Rica for one year, which yielded 4332 species of Diptera, providing the first verifiable basis for diversity of a major group of insects at a single site in the tropics. In total 73 families were present, all of which were studied to the species level, providing potentially complete coverage of all families of the order likely to be present at the site. Even so, extrapolations based on our data indicate that with further sampling, the actual total for the site could be closer to 8000 species. Efforts to completely sample a site, although resource-intensive and time-consuming, are needed to better ground estimations of world biodiversity based on limited sampling.

An aqueous suspension of the nuclear polyhedrosis virus of Lymantria dispar (L.), LdNPV, was fed to third-instar caterpillars of L. dispar and 46 species of nontarget Lepidoptera in four successive. 24- to 48-h doses of 3 × 104 polyhedral inclusion bodies (PIBs) in 2 μL applied to small pellets of artificial diet or isolated surfaces of foliage. Adults of the fly Cyrtophleba coquilletti Aldr., and adult males of the bee Megachile rotundata (Fabr.), were assayed with a single dose of 1.2 × 105 PIBs in 2 μL of 30% sucrose solution. Only those specimens that completely consumed the dose(s) were transferred to appropriate maintenance conditions for 7–10 days whereupon they were frozen. Samples of macerates of experimental specimens were dot-blotted onto nylon membranes on which whole genomic LdNPV DNA-probing and chemiluminescence techniques were used lo show presence of LdNPV DNA. With reference to positive and negative controls, the 48 nontarget species were diagnosed as nonpermissive of LdNPV but the target species was clearly infected. This study demonstrates a high degree of host-specificity of LdNPV.

Pitfall traps containing a preservative have become the standard method of sampling for epigeal invertebrates such as carabid beetles and cursorial spiders. However, they often result in high levels of mortality for small mammals and amphibians. We compared the carabid, spider, and vertebrate captures within five pitfall trap types (conventional trap, funnel trap, shallow trap, Nordlander trap, and the ramp trap) to determine the trap type that would reduce vertebrate incidental catch without compromising the capture of invertebrates. We also examined the effect of a mesh screen over pitfall traps on carabid beetle and vertebrate catches. All modifications to the conventional trap design resulted in a reduction in both small mammal and amphibian captures. The shallow pitfall trap and the funnel trap captured a carabid beetle and spider fauna similar to that captured by the conventional trap. The species compositions of the ramp trap and the Nordlander trap were different from those of the other trap types, but these traps were more efficient, capturing more species per individual captured. The ramp trap appeared to be the method of choice for sampling epigeal spiders. Thus, the choice among trap designs for invertebrates depends on the objectives of the study. However, an alternative to the conventional trap design should always be considered to reduce small mammal mortality.Résumé-Les pièges à fosse contenant un liquide de conservation constituent la méthode standard pour la récolte d'invertébrés épigées, tels que les coléoptères carabidés et les araignées coureuses. Cependant, leur usage entraîne souvent de fortes mortalités de petits mammifères et d'amphibiens. Nous avons comparé les récoltes de carabes, d'araignées et de vertébrés dans cinq types de pièges à fosse (modèle ordinaire, en entonnoir, à forme surbaissée, type Nordlander et à rampe) afin de déterminer le type de piège qui permette de réduire les captures accessoires, sans minimiser la récolte d'invertébrés. Nous avons aussi examiné l'effet d'un grillage au-dessus du piège sur les récoltes de carabes et de vertébrés. Toute modification du modèle ordinaire entraîne une réduction des captures de petits mammifères et d'amphibiens. Les pièges à forme surbaissée et en entonnoir récoltent une faune de carabes et d'araignées semblable à celle du piège ordinaire. La composition en espèces des récoltes au pièges de type Nordlander et à rampe diffère de celle des autres types, mais ces pièges sont plus efficaces et capturent un plus grand nombre d'espèces par individu. Le piège à rampe semble être la méthode privilégiée pour l'échantillonnage des araignées épigées. Le choix d'un type de piège pour la capture des invertébrés dépend donc des objectifs de l'étude. Cependant, on doit toujours envisager l'utilisation d'un modèle de rechange au piège ordinaire afin de réduire la mortalité des petits mammifères.[Traduit par la Rédaction] 233 Fig. 3. Dendrogram based on the relative Bray Curtis similarity measure and weighted average cluster analysis describing the s...