The aster leafhopper, Macrosteles quadrilineatus Forbes, is an important pest of fresh market vegetable crops as the primary vector of the aster yellows (AY) phytoplasma. Two sampling methods, sticky trapping and inverted cage trapping, were used to monitor male and female leafhopper populations over three growing seasons in leaf lettuce fields in Ohio. Captures by one sampling method could not be used to estimate captures by the other method, because sticky traps captured significantly more male leafhoppers and cage traps captured significantly more females. The proportion of females collected in cage traps decreased significantly in individual plantings as lettuce matured and also over the course of the season in one of 2 yr of sampling by using both techniques. Subsamples of captured leafhoppers were tested for AY phytoplasma infection by using a polymerase chain reaction (PCR) assay. In one year of our study, more male than female leafhoppers were infected with AY phytoplasma. Because the field distribution of insect-vectored diseases can reveal information about vector movement, as well as vector identity, spatial analysis was performed. Analyses indicated the distribution of symptomatic AY phytoplasma-infected lettuce plants was significantly clustered and followed a beta-binomial distribution. Our data suggest that females may be responsible for at least the early season inoculation of clustered symptomatic lettuce plants.

Cauliflower mosaic virus (CaMV) is transmitted to crucifers in a noncirculative manner by several aphid species. CaMV is preferentially acquired from the phloem, although acquisition also occurs after brief intracellular stylet punctures of aphid vectors in nonvascular leaf tissues. In the present work, we used the electrical penetration graph technique to study the specific aphid stylet activities and behavioral events leading to the inoculation of CaMV to turnip plants by its two major vectors, Brevicoryne brassicae (L.) and Myzus persicae (Sulzer). Aphids subjected to an 8-h acquisition access time on infected plants were transferred to test plants and removed immediately after specific behavioral events were recorded. CaMV was readily inoculated after the first intracellular puncture in nonvascular tissues by both vector species. Inoculation rate of CaMV by B. brassicae was the highest after a 3-h inoculation access period, regardless of whether aphids had reached the phloem phase during that period. Consistent interspecific differences also were found in the ability of both aphid vectors to retain CaMV. B. brassicae could retain the virus after several intracellular punctures, whereas M. persicae readily lost the virus after performing the same number of intracellular stylet punctures. We concluded that salivation by aphids during successive intracellular stylet punctures in the epidermal and mesophyll cells before reaching the phloem phase are the key behavioral events associated to the inoculation of Cauliflower mosaic virus. The likely location of the viral retention site inside the aphid mouthparts is discussed.

Retention or loss of transmissibility after molting was tested for adult and nymphal squash bug, Anasa tristis (De Geer), a natural vector of the plant pathogen Serratia marcescens Bizio, the causal agent of cucurbit yellow vine disease. Squash bug adults and nymphs fed from bacteria-infiltrated squash cubes were caged on squash test plants and transferred weekly to new plants for eight consecutive weeks. Twelve percent of the bugs that acquired as adults transmitted the bacterium to at least one of the test plants; 75% of these transmitters inoculated more than one plant. Transmission to plants occurred as late as 3 to 8 weeks postacquisition. Ten percent of squash bugs that fed on S. marcescens as fifth instars inoculated plants after molting to the adult stage; 77% of these transmitters inoculated more than one plant. Two insects that fed on S. marcescens as third instars inoculated squash plants. When examined by scanning electron microscopy, the foregut cibaria of transmitting insects were free of bacteria-like structures. The ability of A. tristis to transmit S. marcescens after molting to the adult stage suggests that the hemocoel acts as the site of retention of transmissible bacteria.

Xylella fastidiosa is a xylem-limited bacterium transmitted to plants by xylem sap-feeding insects. This pathogen has a wide host range, causing disease in crops such as grape, citrus, almond, and coffee; ornamental plants; and trees. Sharpshooter leafhoppers are the major vectors of X. fastidiosa to crops of economic importance. Transmission characteristics include the lack of a latent period, no transstadial or transovarial transmission, persistence in adults, and multiplication in the foregut of vectors. Various factors influence vector transmission of X. fastidiosa, including the distribution and density of bacterial populations in host plants, insect host range and plant preference, season of inoculation, and climatic conditions. The ecology of vectors can affect epidemics, as demonstrated by the large increase in Pierce’s disease of grapevine incidence in California after the introduction of Homalodisca coagulata (Say). Disease control strategies should incorporate basic knowledge of transmission biology, vector ecology, and other interactions involved in X. fastidiosa diseases. We discuss basic aspects of X. fastidiosa transmission by vectors, the ecology of insects in relation to transmission and disease spread, and how basic research can be applied to the development of management strategies for a X. fastidiosa disease.

The sharpshooter Homalodisca coagulata (Say) (Hemiptera: Cicadellidae: Cicadellinae) is an exotic vector of the Pierce’s disease (PD) bacterium, Xylella fastidiosa (Wells et al.), that was first observed in California in 1989. H. coagulata has since greatly increased the threat of PD to the grape industry as well as stone fruit, nursery, and ornamental industries in California. This is the first in a series of articles that together describe how sharpshooter stylet penetration behaviors (especially intricate stylet activities, salivation, and ingestion) control transmission (i.e., acquisition and inoculation) of X. fastidiosa. Herein, we categorized and characterized alternating current electrical penetration graph (EPG) waveforms from glass-winged sharpshooter stylet penetration on petiole of susceptible grape (‘Cabernet Sauvignon’), paying special attention to waveform fine structures that are likely to be the key to detecting the instant of inoculation. We also correlated waveforms with salivary sheath termini in grape tissues. For the first time in any EPG study of leafhopper or planthopper feeding, we demonstrate through case studies of individual probes how to follow the process of stylet penetration step by step as it is occurring, including salivary sheath branching and when the stylets first puncture a xylem cell. Finally, we discuss the implications of our findings for understanding the transmission mechanism of X. fastidiosa, in comparison with hypothesized mechanisms in the literature.

The sharpshooter Homalodisca coagulata Say (Hemiptera: Cicadellidae) is a polyphagous insect that feeds primarily from the xylem vessels of host plants. This insect is an efficient vector of the xylem-limited, plant-pathogenic bacterium Xylella fastidiosa Wells, which is the causal agent of several important diseases in ornamental and agricultural crops. In wild populations, H. coagulata have been observed to almost exclusively orient with their anterior facing toward the roots (AFR), regardless of branch position. The orientation of H. coagulata seemed to be chosen before stylet insertion. Neither masking plant chemical and morphological surface cues nor placing test plants in the absence of light affected body posture. The introduction of 1.5-V direct current electricity to the plants resulted in altered body positioning. Removal of both front tarsi influenced body position; however, removal of only the right or left front tarsi had no effect on H. coagulata body position. Removal or masking of right, left, or both antennae resulted in altered body position.

The distribution of corn stunt spiroplasma (Spiroplasma kunkelii, class Mollicutes, family Spiroplasmataceae, CSS) in its leafhopper vector Dalbulus maidis (DeLong & Wolcott) was studied by immunofluorescence confocal laser scanning microscopy (iCLSM), by using three preparation methods: dissected whole-mount leafhopper organs, thick sections of paraffin-embedded leafhopper parts, and smears of leafhopper hemocytes. These methods combined revealed the localization of CSS in the midgut, filter chamber, Malpighian tubules, hindgut, fat tissues, hemocytes, muscles, tracheae, and in several lobes of the salivary glands. However, CSS was not detected in nerve cells of the brain or other nerve ganglia of CSS-infected D. maidis. The percentage of leafhoppers with detected CSS in various organs/tissues 2 to 3 wk post-exposure to CSS-infected plants for 1 wk was up to 95%, and 75% of these leafhoppers inoculated CSS into maize, Zea mays L., test seedlings before iCLSM processing. Using thick sections from CSS-infected maize leaves, iCLSM was also used to localize CSS in phloem tissues of maize plants. Although transmission electron microscopy (TEM) provides higher resolution for the localization of mollicutes or other pathogens in host plants and insect vectors/hosts, iCLSM has the following advantages compared with TEM: 1) processing and examination of specimens is considerably faster; 2) much larger and more numerous samples can be processed; and 3) the distribution of pathogens can be studied in whole organs or even the entire insect (through thick sectioning). Additionally, compared with epifluorescence microscopy, iCLSM provides three-dimensional images of the studied organs, indicating their spatial relationships, which can be valuable for studying the routes of pathogens in their vectors.

Phylogenetic analysis of the Bemisia tabaci (Gennadius) mitochondrial cytochrome oxidase I (mtCOI) sequence grouped populations into one of four major phylogeographic lineages, represented as groups from The Americas-Caribbean Basin (New World) (n = 41), Mediterranean-North Africa-Middle East (n = 47), Asia-Australia (n = 52), and Sub-Saharan Africa (n = 29). The mean genetic variation and percentage nucleotide identities indicated that whitefly populations from the Southeast Asian/Australian region were the most genetically divergent (1% per lineage/10⁶ yr), whereas the Western Hemisphere (Americas-Caribbean region) populations exhibited the lowest degrees of divergence. The phylogenetic tree for the genus Begomovirus (Geminviridae) coat protein (CP) revealed two major phylogeographic lineages with a basis either in the Eastern or Western Hemisphere, respectively. Within the Eastern Hemisphere lineage, the viral CP grouped in one of the three major geographical regions, which were analogous to the mtCOI for the respective geographically associated whitefly populations. Analysis of the CP for the Western Hemisphere viruses revealed two sublineages representative of the 1) North and Central Americas/Caribbean Basin, and 2) South American continent, respectively, which also were phylogeographically concordant with the two major Western Hemisphere B. tabaci mtCOI groups. Analysis of the base substitution rates and synonymous and nonsynonymous changes for the B. tabaci mtCOI coding region suggested that this gene has evolved under positive selection. In total, 26 polymorphic sites (11%) were identified for the species complex, and the fixation of certain amino acids was more evident within certain lineages or populations than others. Collectively, the majority of the 26 polymorphic sites were located at the C-terminal end of the mtCOI fragment that was examined herein. Of the 26 polymorphic sites, only two were net charge-altering amino acids (Y407H and G486K). The genetic differentiation coefficient (G_ST) for the B. tabaci complex was 59.9%, suggesting that at least moderate genetic differentiation has occurred for the four major extant phylogeographic lineages. This observation is in line with available extant biotic (exclusive vector of begomoviruses; transmission determinants linked to viral CP), morphological (no unique characters), and genetic evidence (single group based on mtCOI, 16SrDNA, and ITS-1 analysis), which supports the hypothesis that B. tabaci comprises a single albeit, cryptic species. Taxonomically, B. tabaci is a species complex, which likely has and continues to experience restricted gene flow in part as the result of geographical and/or host range restrictions.

Spilonympha, a new subgenus of the genus Wyeomyia Theobald, is described based on morphological characters of the adult, larval, and pupal stages. The taxonomic species included in the new subgenus are Wyeomyia mystes (Dyar), Wy. bourrouli (Lutz), Wy. forcipenis Lourenço-de-Oliveira & Silva, Wy. finlayi Lane & Cerqueira, Wy. airosai Lane & Cerqueira, Wy. howardi Lane & Cerqueira, and a new species designated Wy. aningae, which is described and illustrated. Wy. aningae was designated as the type species of the new subgenus. The systematic treatment of these species includes a key for the identification of the adult males, pupae, and larvae; bionomics data; and geographical distribution.

A new species of Iraella Nieves-Aldrey, Iraella hispanica n. sp. (Hymenoptera: Cynipidae), is described from northeastern Spain. The new species induces plurilocular galls on terminal flower buds of the common poppies Papaver rhoeas L. and Papaver dubium L. (Papaveraceae). The terminal-instar larva also is described. I. hispanica represents the second known species of the genus Iraella and is related to Iraella luteipes (Thomson), a species inducing cryptic galls in stems of Papaver somniferum L. Characters separating adults, larvae, and galls of both species are given as well as life cycle data. Comments on an associated parasitic species of Figitidae, Parnips sp. cf nigripes (Barbotin), are provided. The phylogenetic relationship of the new species with a clade of cynipids associated to Papaver plant species is discussed.

For the first time, the eggs and all instars of a species of the Indian genus Linshcosteus are described using morphometrics and optical and scanning electron microscopy. Linshcosteus karupus Galvão, Patterson, Rocha & Jurberg, 2002 was recently described from near Kalakkadu, Tamil Nadu State, southern India. In addition, current knowledge and the importance of morphological studies of immature Triatominae are discussed.

Rapidly evolving nuclear coding sequences are highly desirable for phylogenetic studies of closely related species. Here, we investigated an 807-bp region, homologous to the testis-specific Tektin gene from Bombyx mori (L.), in 34 nymphalid butterfly taxa in the subfamilies Ithomiinae, Danainae, and Heliconiinae. Within Ithomiinae, relationships inferred from Tektin sequence data were remarkably similar to those in trees based on combined morphological and ecological data. Partitioned Bremer analysis, with mitochondrial cytochrome oxidase I and II, and nuclear wingless and elongation factor 1-α sequences, revealed Tektin to have the greatest utility for inferring relationships at the genus, tribe, and subfamily levels across the studied taxa. We think Tektin will provide a useful source of molecular characters for inference of relationships among other butterflies, and perhaps among other insect taxa.

Siamusotima aranea Solis & Yen, is a new stem-boring musotimine species from Thailand. It was discovered in the stems of Lygodium flexuosum (L.) Sw. (Schizaeaceae) during exploration for biological control agents of Lygodium microphyllum (Cav.) R. Br., the Old World climbing fern. This is the first report in the Pyraloidea of a stem-boring larva with unique modifications of the anal segment resembling that of tenebrionid beetle immatures and with observations of possible mimicry between the adult moth and spiders.

The Western Palaearctic taxa of the Neocrepidodera impressa (F.) and Neocrepidodera ferruginea (Scopoli) species groups are reviewed. Twelve species are recognized, two of them newly described, N. carolinae sp. nov. from High Atlas, Morocco, and N. precaria sp. nov. from southern Spain and northern Morocco. Two other species are raised from the subspecific status, N. hispanica (J. Daniel) stat. nov. and N. peregrina (Harold) stat. rev., taking into account their constant marked external and genital differences with N. crassicornis (Falderman) and N. impressa (F.), respectively. A key for the Western Palaearctic region is provided, including external, male and female genital features for each taxon. Special effort was devoted to the identification of females, finding that vaginal palpi show useful diagnostic characters. Figures of pronotum, aedeagus, vaginal palpi, and spermatheca are presented for all species.

Random amplified polymorphic DNA (RAPD) diagnostic bands are one tool used to differentiate cryptic mosquito species in the Anopheles albitarsis Complex. Monophyly of four species (A. albitarsis Lynch-Arribálzaga, A. albitarsis B, A. deaneorum Rosa-Freitas, and A. marajoara Galvão & Damasceno) currently identified with the RAPD technique was assessed using sequences of the cytochrome oxidase I (COI) mitochondrial DNA (mtDNA) gene. Maximum parsimony, maximum likelihood, and Bayesian analyses support monophyly for A. albitarsis s.s., A. albitarsis B, and A. deaneorum. Anopheles marajoara, as identified by RAPD banding patterns, was either polyphyletic or paraphyletic in all phylogenetic analyses. The phylogenetic pattern and within-species genetic distances observed in A. marajoara suggest the existence of a previously unidentified species (species E) in northern Brazil and Venezuela. Diagnostic RAPD bands were unable to distinguish between A. marajoara and species E, probably because of the low number of correlated bands used to identify species and weaknesses of the RAPD technique, in particular, violations of the untested assumption of homology of comigrating bands. A. marajoara (even without species E) is paraphyletic with respect to A. deaneorum; if A. deaneorum is a separate species from A. marajoara, then A. marajoara may consist of two or more species in Amazonian Brazil. Based on mtDNA COI sequences, there are at least four phylogenetic species within the Albitarsis Complex: A. albitarsis s.s., A. albitarsis B, A. marajoara, and species E; the species status of A. deaneorum is ambiguous.

A phylogeny was reconstructed for four species belonging to the Neotropical Anopheles (Nyssorhynchus) albitarsis complex using partial sequences from the mitochondrial cytochrome oxidase I (COI) and NADH dehydrogenase 4 (ND4) genes and the ribosomal DNA ITS2 and D2 expansion region of the 28S subunit. The basis for initial characterization of each member of the complex was by correlated random amplification of polymorphic DNA-polymerase chain reaction (RAPD-PCR) markers. Analyses were carried out with and without an outgroup (An. (Nys.) argyritarsis Robineau-Desvoidy) by using maximum parsimony, maximum likelihood, and Bayesian methods. A total evidence approach without the outgroup, using separate models for “fast” (COI and ND4 position 3) and “slow” (rDNA ITS2 and D2, and COI and ND4 position 1) partitions, gave the best supported topology, showing close relationships of An. albitarsis Lynch-Arribálzaga to An. albitarsis B and An. marajoara Galvão & Damasceno to An. deaneorum Rosa-Freitas. Analyses with the outgroup included showed poorer support, possibly because of a long branch attraction effect caused by a divergent outgroup, which caused one of the An. marajoara specimens to cluster with An. deaneorum in some analyses. The relationship of the above-mentioned result to a separately proposed hypothesis suggesting a fifth species in the complex is discussed.

We tested host plant suitability of 10 taxa in the Rhamnaceae for successful preoverwintering development of soybean aphid, Aphis glycines Matsumura (Homoptera: Aphididae). In the laboratory, we offered each gynopara and ovipara a single member of each putative host plant and measured survivorship and fecundity. Rhamnus cathartica L. and Rhamnus alnifolia L’Héritier were confirmed as suitable host plants, and eight other taxa were confirmed as unsuitable. This study supports results from a companion study in which soybean aphids were offered multiple members of the Rhamnaceae in field cages. Of the two suitable host plants, R. cathartica supported greater longevity and oviposition rates in oviparae. The importance of R. cathartica as an overwintering host to soybean aphid ecology and management is discussed.

The Klamath-Siskiyou ecoregion of northern California is one of the most diverse temperate coniferous forests. A network of “late successional reserves” (LSRs) has been established to maintain characteristics of late successional forest and to promote late successional characteristics in younger stands. Also, an important goal of conservation management is the maintenance of genetic diversity of ecologically important species. However, this management strategy has not yet been implemented among the LSRs. This study examined the level of genetic diversity among populations of a soil-inhabiting beetle, Acrotrichis xanthocera (Matthews) (Ptiliidae), within the LSR network. Using a partial DNA sequence of the mitochondrial cytochrome oxidase I gene, a total of 31 haplotypes were identified for 117 individuals. Genetic fixation indices and phylogenetic and nested clade analyses all suggest moderate gene flow among five LSR and five non-LSR populations. In addition, haplotype diversity was high and the occurrence of unique haplotypes was common for most populations, which suggests current or past isolation of some populations. These results suggest the LSR network maintains considerable genetic variation for this beetle. However, the genetic variation was not equally distributed among the LSRs. Thus, to facilitate gene flow throughout the ecoregion, it is suggested that future LSRs should reduce gaps among the current LSRs.

Nearly 5,000 historical and contemporary specimen records of stoneflies (Plecoptera) from Illinois demonstrated that this fauna is highly imperiled, boding poorly for aquatic insect communities in North America and elsewhere. Losses include two extinctions of endemics and 20 extirpations of 77 total species, a rate of loss that is higher than for either mussels or fish in Illinois. Another 19 species (24.7%) were designated as critically imperiled, being known from five or fewer locations. Two families, Perlidae and Perlodidae, experienced the greatest number of losses. Species lost were mostly those with longer life cycles and direct egg hatch. Three historically hyperdiverse regions were identified and losses in all 14 natural divisions were documented. Large river habitats and historically prairie regions have experienced the greatest proportional losses of species. This scenario probably follows for Ephemeroptera, Trichoptera, and Odonata in the Midwest and in other areas with similar glacial and cultural histories.

Thirteen transverse latitudinal transects are used to examine the biogeographic pattern of the peninsula effect on 341 species of Florida carabid beetles. In this fauna, 278 species are grouped to be of temperate affinity or origin, 28 of tropical affinity or origin, and 35 are endemic to Florida; 39 of the species are flightless. The species are ecologically grouped as riparian, hygrophile, halophile, mesophile, subxerophile, arboricole, and endogean. Both the total fauna and the temperate group show a peninsula effect, that is, a decrease in species richness from peninsula base to tip. The tropical group shows an inverse peninsula effect: their species richness decreases toward the base. The endemic group displays a much different pattern, with maximum richness at the middle of the peninsula, a possible reflection of former Tertiary or Quaternary islands as centers of isolation and speciation. Over-water dispersal has been important: 61 species crossed the water gap between Florida and West Indies; 36 temperate species moved from Florida into the West Indies; 25 West Indian (tropical) species have crossed the water gap into Florida (69% of these are preadapted hygrophilic, riparian, and halophile species). Species movements between Florida and the West Indies were probably more prevalent at times of Pleistocene low sea levels, when these lands were larger in area and closer to each other. The Gulf Coastal Plain has provided an avenue for carabid movement to and from Florida and the continental Neotropics with 44 species occurring in both areas, and 70% of these are preadapted hygrophilic, riparian, and halophilic species.

Isolated cellular nidi stem cells from the anterior and posterior midgut of larvae of the red turpentine beetle, Dendroctonus valens LeConte, proliferate and differentiate in vitro when cultured in RPMI 1640 medium, in the presence of 20-hydroxyecdysone, fat body extract from Zophobas morio (Blanchard) (Coleoptera: Tenebrionidae) pupae, and conditioned medium. Our data suggest that the stem cells did not increase exponentially as in typical cultures. However, the early presence of stem cells in larval cultures indicates that the proliferation process is higher than in cultures from adult D. valens. After 2 wk in culture, up to 10% of cells were observed in various stages of differentiation. The mean duration of midgut cultures was 82 d.

Expression of heat shock protein 70 (Hsp70) is widely regarded and used as an indicator of cellular stress. However, recent data suggest that insect diapause may inhibit the increased expression of Hsp70 typical of the heat stress response. Here, we evaluated Hsp70 expression after heat stress in relation to diapause, in blueberry maggot, Rhagoletis mendax Curran (Diptera: Tephritidae), pupae. First, the respiration rates of laboratory-reared pupae were measured to estimate the limits of diapause. Then, toward the beginning and completion of diapause, pupae in prediapause, diapause, and postdiapause were exposed to similar periods of heat stress consisting of 1 h at 25 (control), 36, 40, and 44°C. Pupae were immediately frozen, and Hsp70 expression was determined by SDS-PAGE, Western blot, and immunodetection using a monoclonal antibody specific for heat-inducible Hsp70. Hsp70 was present at normal temperature (25°C) in diapausing pupae both toward the beginning and completion of diapause. Expression of Hsp70 always increased after heat stress irrespective of the diapause status of the pupae. These data support previous findings suggesting the presence of Hsp70 throughout diapause and indicate that even during diapause Hsp70 expression is responsive to heat stress. These results support the use of Hsp70 expression to study differential adaptation to heat stress during pupal diapause.

In the past 20 yr, populations of Cicindela hirticollis Say (Coleoptera: Cicindelidae) that inhabit river shorelines have declined dramatically. These habitats have routinely flooded in winter and spring historically, but they have been altered by damming and controlled water releases for irrigation and power generation. We tested the ability of C. hirticollis larvae from two river and one bayshore population to survive immersion in severely hypoxic water. This is the first report of population-level differences among insects in immersion survival and likely relates to exposure to different flooding regimes. The larvae from the Chesapeake Bay population survived ≈3 d of immersion, and those from river populations survived about a day longer. Despite survival differences between riverine and seashore populations, recovery times after exposure to severe hypoxia were comparable. Second and third instars from the seashore population had similar survival at 9.0 and 16.5°C. Survival times of larvae more than doubled under aerated conditions. Adults survived >30 h of immersion in severely hypoxic water, substantially longer than reported for other tested tiger beetle species. Although riverine populations survive longer periods of immersion, dams cause habitats used by riverine populations of this species to be inundated for weeks at a time, far longer than larvae were able to survive under hypoxic or aerated conditions in the laboratory. Thus, alteration of flooding regimes and subsequent larval habitat immersion is probably a major cause of the observed decline of riverine populations of C. hirticollis. Moreover, these data represent the first report of significant physiological differences among populations of an insect species exposed to different frequencies of immersion and thus have both important experimental and evolutionary implications.

A molecular genetics study involving DNA sequencing of a portion of the mitochondrial DNA 16S gene was undertaken to determine the extent of genetic variation within Reticulitermes flavipes (Kollar) in North America. This study was done because differences in morphological variants (of R. flavipes) would presumably translate into genetic differences, and there are no prior studies that describe its genetic variation from the extent of its North American range. In total, 493 samples were analyzed from the United States, Canada, and Mexico. Nineteen nucleotide sites were variable in the 428-bp mitochondrial DNA (mtDNA) sequence, and 47 mtDNA haplotypes were observed. Nine haplotypes (19%) occurred only once, whereas the most common haplotype, F, occurred in 17% of the samples. Four haplotypes were found over a broad geographical range encompassing at least nine states each. The single haplotype found in Toronto, Canada, also occurs in Arkansas, whereas two of the three haplotypes found in Mexico are unique to that country. Based on this research, there seems to be numerous R. flavipes haplotypes that are widespread, perhaps due to human involvement, whereas other haplotypes may be more rare and could represent locally adapted populations.

Colorado potato beetle, Leptinotarsa decemlineata (Say), is the most important insect defoliator of potatoes and is infamous for its ability to develop insecticide resistance. Sperm precedence is an important consideration in developing resistance management plans. We determined the precedence of sperm from a postdiapause spring mating by using irradiated sterile males. We also investigated whether spring mating (with or without fertilization) affects reproduction of overwintered females. Precedence of sperm from spring matings versus overwintered sperm from fall matings was almost complete. Some fertilization from fall matings did take place in this experiment, but it exceeded 10% in only one of the 22 pairings. Females mated only the previous fall laid fewer eggs than spring-mated females, but spring mating did not seem to improve the hatch rate of deposited eggs. On average, mated females started laying 1.6 d sooner than fall-mated females, but this difference was not significant. Hatch rate did not change with time. Precedence of spring matings over stored sperm can help compensate for assortative summer mating among resistant individuals due to differences in developmental time between refuges and treated areas.

Variation in pupation site preference is hypothesized to drive the evolution of environmentally cued pupal color dimorphism in swallowtail butterflies. Support for this hypothesis comes from comparisons of natural pupation sites of species monomorphic and dimorphic for pupal color. Here, we show that interspecific differences in pupation site preferences in nature are to a large extent mimicked in a controlled common garden experiment, suggesting that these differences are genetic. We gave larvae of three swallowtail species a choice of yellow and blue surfaces for pupation. Given the absorption spectra of green vegetation and the spectral sensitivities of the larval eyes, yellow and blue surfaces should be strong indicators of green and brown pupation sites, respectively. Papilio glaucus L., which produces only brown pupae and pupates near the ground in nature, chose to pupate near the bottom of the blue surfaces. In contrast, Battus philenor (L.) and Eurytides marcellus (Cramer), which produce dimorphic pupae, chose to pupate on both yellow and blue surfaces. B. philenor typically chose sites on blue surfaces that were significantly higher than were those of P. glaucus. We also found no differences between geographic populations of B. philenor. The distribution of pupation heights for E. marcellus was bimodal, possibly indicating a genetic polymorphism in pupation site preference. In a separate experiment, we asked whether rearing photoperiod affected pupation site preferences in Papilio polyxenes F. as suggested by observations in the field. Our results showed a clear effect, with larvae choosing only brown pupation sites when reared on an autumnal photoperiod.