An optical sensor was used to make digital recordings of wingbeat waveforms for the five most common aphids found on Guam: Aphis craccivora Koch, A. gossypii Glover, A. nerii Fonscolombe, Pentalonia nigronervosa Coquerel, and Toxoptera citricida (Kirkaldy). Wingbeat frequencies for each species overlapped all other species. However, mean wingbeat frequencies were significantly different for all species. Wingbeat frequencies and harmonic patterns were extracted from the recordings and submitted to cluster analysis, which failed to separate species completely. Several nearest neighbor and probabilistic neural network classifiers were built using time series, frequency spectra, wingbeat frequencies, and harmonic patterns as input variables. These classifiers were evaluated by having them identify wingbeat waveforms from aphids collected and recorded after their construction. The best performing classifier model was a probabilistic artificial neural network trained using 256-bin frequency spectra as input. Sixty-nine percent of the waveforms presented to this network were identified correctly. This study demonstrates the feasibility of developing an insect flight monitor that automatically counts and identifies individual flying insects. Essential components of the monitoring system are a photosensor, a multimedia personal computer, and software that identifies wingbeat frequency spectra using an artificial neural network.

Eupithecia robinsoni sp. nov. is described from the Juan Fernández islands. This species is associated with Gunnera peltata Phil. The egg, larva, pupa, adult, and genitalia are described and illustrated. Preliminary results of the natural history of this species are given and compared with biology of E. horismoides Rindge, 1987.

Phylogenetic relationships among the genera of Apochrysinae are examined. Exemplars from all 13 previously defined genera of the subfamily are compared with outgroups from the Nothochrysinae (Nothochrysa McLachlan) and Chrysopinae (Italochrysa Principi) in a parsimony analysis of 78 character states across 39 adult morphological characters. The analysis resulted in three most parsimonious trees with a length of 70 steps. The Apochrysinae are confirmed as monophyletic, with the enigmatic genus Nothancyla as the sister to the rest of the subfamily. The phylogenetic relationships among the genera of Apochrysinae are discussed, as are primitive and derived venational characters and wing vein reticulation in apochrysine wings. Six valid genera are recognized in light of the analysis: Apochrysa Schneider (Anapochrysa Kimmins, Lauraya Winterton, Nacaura Navás, Oligochrysa Esben-Petersen and Synthochrysa Needham, syns. nov.), Domenechus Navás, Joguina Navás (Lainius Navás syn. nov.), Loyola Navás (Claverina Navás syn. nov.), Nobilinus Navás and Nothancyla Navás. Valid genera are rediagnosed in a revised classification. A new key to genera and lists of included species are presented.

Mitochondrial 16s rDNA was sequenced from nine different populations of Aphelinidae and 10 of aphidiinae. Sequence divergences between populations within a species are low, ranging from 0 to 0.38%. Divergences among species within the same genus range from 0 to 8.71%. Aphelinus asychis Walker has a sequence divergence from the other Aphelinus spp. of 8.71%, which is even higher than the divergences among the aphidiine genera Lysiphlebus, Aphidius and Diaeretiella. Our 16s rDNA phylogeny for aphidiines is concordant with a previously published NADH1 dehydrogenase phylogeny. Our analysis identifies a complex comprising A. albipodus (Hayat & Fatima), A. varipes (Foerster), and A. hordei (Kurdjumov). The sequence divergences within this complex are low, ranging from 0 to 0.38% with an average of 0.19%, which suggests that the three species within the A. varipes complex diverged within the last ≈90,000 yr.

Databasing of all Ephemeroptera and Plecoptera specimens in the Illinois Natural History Survey Insect Collection has recently been completed. Both databases are Internet-searchable in a simplified format ( http://www.inhs.uiuc.edu/cbd/EPT/index.html). Analysis of the databases shows that the Plecoptera are at a much better level of determination than the Ephemeroptera, with 88% of the specimens determined to the species level. Only 22% of Ephemeroptera specimens have been determined to species. The Ephemeroptera collection is also much more narrow in geographic scope, with 74% of determined specimens from Illinois. In contrast, only 30% of determined Plecoptera specimens are from Illinois, with most of the remainder being from across the United States. Four new Illinois records were uncovered in the Ephemeroptera database: Caenis diminuta Walker, C. punctata McDunnough, Pseudocloeon ephippiatum (Traver), and Serratella deficiens (Morgan). Analyses of the data document range reductions in Illinois of the stonefly Neoperla clymene (Newman) and the mayfly Pseudiron centralis McDunnough, range expansion in the stonefly Perlesta nelsoni Stark, and a shift in the prevalence of perlid stonefly species assemblages from Acroneuria in the first half of the 20th century to Perlesta in the second half. We also discuss the change in Plecoptera diversity between historic and modern records from Illinois, and compare the relative stability of Plecoptera species assemblages from the major ecological regions of the state. We encourage entomologists to find other uses for these data and to contribute a growing pool of historic specimen-level data at their own institutions.

A parasitoid wasp larva is described emerging from an adult ant (Lasius sp.) in Eocene Baltic amber. On the basis of the cephalic structures of the parasitoid, it can be assigned to the subfamily Neoneurinae of the family Braconidae. This is the only extant subfamily of Hymenoptera whose females oviposit in adult worker ants. This discovery, which is the first fossil demonstrating insect parasitism of ants, shows that ant parasitism by Braconidae was well established some 40 million years ago. The parasitoid could belong to the extinct neoneurine, Elasmosomites primordialis Brues, which was described earlier from Baltic amber.

The life history and case-making behavior of Phylloicus ornatus (Banks) from two spring-fed first-order streams in the Edwards Plateau bioregion of Texas were studied from January 1998 to November 1999. Field sampling of larvae, pupae, and adults, and laboratory rearings indicated a multivoltine cycle. Eggs averaged 0.32 mm diameter and have distinctive, ridged chorionic sculpturing. First instars differ from late instars in having fewer labral setae and a unique spur-like claw on each lateral hump. Larval development was asynchronous, with second through fifth instars and pupae present most months. First instars were present April through July, October, and November. Case-making of first instars, and case reconstruction of later instars extracted from their cases, was documented by videotape. The chronological aspects of case-building behavior of first and later instars are documented. Case-building was compared with that of two other species in other families. The near-identical sequences suggest that case-making behavior in all three species represents a recapitulation of evolutionary events leading to larval case-making in Spicipalpia and Integripalpia.

Halictus rubicundus Christ is a facultatively social bee demonstrating solitary behavior in regions of cool climate, social behavior in areas of warmer climate, and a mixture of social and solitary behavior in marginal environments. In this article I compare original data to those from previously published studies of H. rubicundus in a variety of environments. I describe nest structure, nest density, bee size, reproductive output, sex ratio, and incidence of predators and parasites. From the patterns that emerge, I conclude that nest-site philopatry is important in structuring populations so that social behavior is favored over bivoltinism in warm climates. The sex ratio of populations is correlated with photoperiod but the relationship is not absolute; therefore, I propose that some other causal factor or a combination of factors, such as temperature or resource availability, is involved. The same mechanism may be responsible for changes in female size during the season. Differences in social behavior do not appear to provide a barrier to reproduction, and the presence of different forms does not imply incipient speciation.

Weekly Prostephanus truncatus (Horn) flight activity, measured as the density of captured beetles in pheromone baited traps, was monitored for 76 consecutive weeks at 16 sites inside the Lama forest in southern Benin and at four sites in maize farmland just outside the forest. Prostephanus truncatus flight activity was consistently higher and the flight activity pattern significantly different near maize stores than at sites inside the forest. Although P. truncatus is known to infest girdled branches of Lannea nigritana (Sc. Elliot) Keay, the P. truncatus flight activity was comparatively low at forest sites where this tree species dominated. The main peak in P. truncatus flight activity occurred earlier in the eastern part of the forest compared with other forest parts. Ordination analysis showed that comparatively higher flight activity in the eastern part of the forest was positively associated with the presence of teak plantations (Tectona grandis L. F.) at trap sites. The spatial distribution of weekly P. truncatus trap catches were found to be significantly aggregated during a 21-wk period, which largely coincided with the early increase in P. truncatus flight activity in the eastern part of the forest. Based on this evidence, it was suggested that P. truncatus individuals disperse from the eastern part of the forest to other forest parts and to nearby agricultural areas, rather than, as has been previously suggested, from maize stores to the forest environment.

Cotesia flavipes (Cameron) is a parasitoid responsible for maintaining populations of sugarcane borer, Diatraea saccharalis (F.), below economic levels in south Texas sugarcane fields. Transgenic sugarcane expressing the snowdrop lectin (Galanthus nivalis agglutinin, GNA) was developed against the Mexican rice borer, Eoreuma loftini (Dyar), the primary pest of south Texas sugarcane. The potential impact of GNA-expressing sugarcane on various biological and fitness parameters of Cotesia flavipes (Cameron) was studied in the laboratory to gain insight on likely effects of the transgenic sugarcane on biological control of sugarcane borer by C. flavipes. Females of C. flavipes were offered sugarcane borer larvae fed one of two diet treatments for oviposition for two successive generations: (1) artificial diet containing transgenic sugarcane tissue or (2) artificial diet containing nontransgenic sugarcane tissue. Small to marginal negative effects of artificial diet containing transgenic sugarcane tissue were evident in the rate of host suitability, number of cocoons and adult parasitoids emerging per host, percentage cocoons yielding parasitoids, and sex ratio and adult lifespan of parasitoids. These effects were variable between the two parasitoid generations examined. In contrast, differences were not detected between diet treatments in rates of host acceptance, egg load of females, and egg to adult developmental periods. The negative effects of transgenic sugarcane on C. flavipes detected in this study are important because GNA levels in the diet (≈0.49% of total protein content) containing transgenic sugarcane tissue were ≈50% of the level expressed in transgenic sugarcane plants. Results are discussed in relation to potential impacts of the transgenic cultivar on biological control of sugarcane borer by C. flavipes.

We tabulated flowering plant species visited by 98 species of Lepidoptera as extracted from records of C. Robertson, who observed >15,000 insect visitors of flowering plants in central Illinois during a 33-yr period. Diversity of Lepidoptera was highest on plant species of the Asclepiadaceae and Verbenaceae, and the greatest number of lepidopteran species visited Verbena stricta Ventenat (Verbenaceae), Aster pilosus Willdenow (Asteraceae), Cephalanthus occidentalis L. (Rubiaceae), and Pycnanthemum flexuosum (Walter) Britton, Sterns, Poggenberg (Lamiaceae). Lepidopterans were particularly abundant on A. pilosus and C. occidentalis. The most polyphagous lepidopteran species were Colias philodice Godart (Pieridae), Danaus plexippus (L.) (Danaidae), Artogeia rapae (L.) [=Pieris rapae (L.); Pieridae], Phyciodes tharos (Drury) (Nymphalidae), Polites themistocles (Latreille) (Hesperiidae), Pontia protodice (Boisduval & LeConte) (Pieridae), and Everes comyntas (Godart) (Lycaenidae), each of which visited flowers of 50 or more plant species. Colias philodice, Phyciodes tharos, and Pontia protodice were the most common species. Most lepidopteran species evidently visited a limited range of nectar plants, which may have implications for species conservation and selecting “butterfly plants” for gardening.

Antennal olfactory receptor neuron responses in the scarab beetle Phyllophaga anxia (LeConte) were investigated using tungsten microelectrodes. Morphological investigations revealed that antennal sensilla are distributed on the entire antennal club lamellae. The female-produced pheromones, L-valine and L-isoleucine methyl esters, were shown to affect two types of olfactory receptor neurons differently. One type of olfactory receptor neurons was excited with increasing pheromone concentrations at low doses (0.01–1 μg), but inhibited at higher doses. The second type was excited only at the high pheromone doses (100–1,000 μg stimulus loading). Both receptor neuron types were affected in the same way by the two pheromone components.

The association between the ventral nervous system and the sperm storage organs in Anastrepha suspensa Loew was examined to elucidate possible mechanisms that may influence sperm transport in the female reproductive tract. Such mechanisms are of importance with respect to the sexual conflict over paternity. A single, abdominal ganglion is present under the first abdominal sternite of A. suspensa. The ganglion is ovoid (L = 280 ± 18 μm ±SD, W = 230 ± 15 μm ±SD) and has a large nerve fiber extending anteriorly to the thoracico-abdominal ganglion and a large, branched nerve fiber extending posteriorly to the reproductive system. The presence of an abdominal ganglion is atypical for the Cyclorrapha flies and its position in the abdomen is atypical for the Insecta. The ganglion’s position suggests that in some taxa the evolutionary trend toward fewer abdominal ganglia has occurred with the concomitant displacement of caudal ganglia to more anterior positions in the abdomen. Nerves extending from this ganglion synapse with muscle fibers at the base of the spermathecae and the surface of the unicellular gland cells surrounding the spermathecal capsule. When stained with HRP Ab, synaptic boutons are also visible along the length of the spermathecal ducts in association with the longitudinal muscle fibers and on the muscle fibers surrounding the ventral receptacle. These findings suggest that females have the potential to affect sperm transport in their reproductive tract.

Wing-coupling apparatuses of five species of cereal aphids [western wheat aphid, Diuraphis tritici (Gillette); corn leaf aphid, Rhopalosiphum maidis (Fitch); bird cherry-oat aphid, Rhopalosiphum padi (L.); greenbug, Schizaphis graminum (Rondani); and the English grain aphid, Sitobion avenae (F.)] were examined under a scanning electron microscope. The scanning electron micrographs showed that the wing-coupling apparatuses of the five cereal aphid species were similar to the structure found in the Russian wheat aphid, Diuraphis noxia (Mordvilko). The wing-coupling apparatuses were composed of a forewing fold and a set of spiral-shaped (or twice-curved) hindwing hamuli. The hindwing hamuli were not fish hook-like (or once-curved) structures. Previous light-microscopy description of fish hook-like hamuli was the result of limited resolving power and field depth of light microscopy. The number of hamuli varied among and within the aphid species. An asymmetric number of the hamuli between the left and right hindwings were also found in all aphids. Rhopalosiphum padi and D. tritici had the least number of the hamuli, ranging from one to four, whereas S. avenae had the most hamuli, ranging from five to seven. Wing-coupling mechanisms and possible use of the hamuli as a taxonomic character are discussed.

Within an anonymous region of honey bee DNA (locus 227) digested with AluI, informative restriction fragment-length polymorphisms (RFLP) were found in Southern blots with a cloned honey bee DNA probe. The probe was subcloned, so that smaller sections of the locus could be analyzed with the polymerase chain reaction (PCR). Further screening of these amplified sections revealed additional useful RFLPs with HinfI. The informative AluI and HinfI polymorphic sites were mapped to a narrow section of the original probe. A total of 14 sub-alleles was found in this region of which five were found only or predominantly in our African samples (Apis mellifera scutellata Lepeletier), three were found only or predominantly in our east European samples (A. m. ligustica Spinola’ A. m. carnica Pollman, and A. m. caucasica Gorbachev), one was found predominantly in our west European samples (A. m. mellifera L. and A. m. iberica Goetze). Significant associations were found between the AluI and HinfI sub-alleles, reinforcing their subspecies group specificity.

Aedes albopictus (Skuse), Asian tiger mosquito, a dengue fever vector, colonized the United States and Brazil ≈15 yr ago. The geographic origin and changes in population structure were examined using DNA sequences of mitochondrial NADH dehydrogenase subunit 5 (ND5). A 450 bp region was amplified by polymerase chain reaction (PCR) and screened for variation by both the single strand conformation polymorphism (SSCP) mutation detection technique and direct sequencing. The United States populations were typified by some local differentiation, but the most common and widespread haplotype was characteristic of the native range (Asian) populations as well. A comparison of the native range populations with the United States populations indicated a shared ancestral origin. The Brazil populations contained private (population specific) haplotypes, indicating no genetic exchange between the Brazil and the United States populations since introduction. Local differentiation was not observed among Brazil populations in contrast to the United States populations; this suggested distinctive dispersal mechanisms in the two countries. Extremely low variability was present in the A. albopictus mitochondrial sequences when contrasted with other taxa, reflecting a history of dispersal from a narrow genetic base. In contrast, relatively high levels of variation in several sequenced nuclear loci indicated the following colonization sequence: (1) the founding population was small, genetic drift had insufficient time to reduce variation at nuclear loci, and (2) populations successively expanded to new geographic areas established from a few founder females.

Genetic sexing strains (GSS) are being developed for use in sterile insect technique programs against the Mediterranean fruit fly, Ceratitis capitata (Wiedemann). Among other important factors, the utility of these new strains depends on the ability of laboratory-reared males to compete efficiently with wild males in mating with wild females in the field. The current study evaluated the mating ability of a new GSS, Cast 191, in competition with wild males. A well-known GSS, Seib 6–96, was also included in the test. The effect of irradiation on the mating competitiveness of the Cast 191 strain was assessed. The results showed that nonirradiated Cast 191 males outcompeted wild males, whereas irradiated males performed as well as wild counterparts. Although Seib 6–96 males performed less efficiently than Cast 191, they did not differ from their own performance reported 2 yr ago. Mating duration of Cast males, either irradiated or not, was not significantly different from the mating duration of wild males. Seib 6–96 had shorter mating duration times than wild and Cast males. These results demonstrated, besides an effect of irradiation on male mating success, a good mating performance of the strain Cast 191.