Taxonomic determination based on morphology alone has failed to describe the evolutionary history of Loxoblemmus appendicularis Shiraki complex in Taiwan. Phylogenetic analysis using the 16S rDNA sequence reveals that three evolutionary lineages of L. appendicularis have been found to coincide with their area of geographical distribution: the Southern, Eastern, and Northern populations. Sequence distance was equal between the Northern and Southern and Northern and Eastern populations (0.032), whereas between the Southern and Eastern populations, the sequence distance was 0.026. Cross-breeding among these three populations has produced abnormal hybrids, suggesting that a possible postzygotic isolating mechanism exists. Biogeographical history suggests the speciation event in L. appendicularis began in the early Pleistocene (1.8 million yr ago [Mya]). Vicariant event created by the rise of the Central Mountain Range >1 Mya led to two separate Eastern and Southern lineages. The following glacial event and formation of a land bridge between Taiwan and the Chinese continent at the end of Pleistocene reintroduced L. appendicularis, currently known as the Northern population, to western and northern Taiwan. Results of sequence divergence, phylogenetic inferences, geographical distribution, and cross-breeding strongly show a current taxonomic recognition of a single species with three parapatric cryptic species.

A distinctive and highly modified but previously unassociated type of aleocharine staphylinid larva was shown by rearing to belong to Hoplandria klimaszewskii Génier, 1989, providing the first knowledge of any larva of the tribe Hoplandriini. Larvae of this species are described, with notes on their feeding and locomotory behavior. Their unique features are extremely large down-turned antennal sensory appendage; very elongate legs with two and one spatulate setae on each pro- and mesofemur, respectively; abdomen very elongate, with tergum and sternum of segment IX fused into a single sclerotized tube uniformly covered with short setae; meso- and metanota and abdominal terga and sterna without anterior cariniform lines; hypertrichous setal patterns (compared with other Aleocharinae) present on all but the head; extremely short urogomphi; and lack of pygopodial gripping structures. The field-collected last instar constructed an apparently silken cocoon covered with soil particles within which it pupated, as known in other Aleocharinae. Along with the reared specimen, other material studied extends the range of H. klimaszewskii from far southern to northeastern Illinois (Cook County, new county record). Larvae from México, Peru, Madagascar, and New Zealand very similar to H. klimaszewskii and presumably representing other hoplandriine taxa have also been seen, although Hoplandriini have not been recorded from New Zealand.

The genus Stigmaeopsis Banks is reinstated with characteristic morphology on distal segment of palpus. Two new species, Stigmaeopsis saharai n. sp. and S. takahashii n. sp., are collected from Hokkaido and described. Five species previously known as celarius species group in Schizotetranychus are moved to Stigmaeopsis. Descriptions are supported by illustrations and scanning electron micrographs.

We redescribe the cicada Tibicen superbus (Fitch, 1855) and designate a neotype and an allotype for the species. The biogeography of the species is provided, including the first records from Mexico. The calling song for the species also is described.

Within the genus Howarthia, Howarthia melli (Forster) is the most frequently reported species across the southern provinces of China. An examination of the type series of H. melli, in combination with results of rearing experiments, reveals that three species have been frequently confused under the name H. melli. The three are superficially similar but not closely related to each other within the genus. H. melli is much more restricted in distribution than previously thought, with most literature records referring to the other two species, Howarthia cheni Chou & Wang and an undescribed species, Howarthia cyanea sp. n., described herein. We provide a discussion of the relationships of these species and a review of Rhododendron-association in Lycaenidae.

Three new species of the Faltala Oman leafhopper group, Kramerana junina n. sp. and K. adusta n. sp. from the Andes Mountains of Peru and Clorindaia brasileira n. sp. from the Serra da Mesa of Brazil, are described. The tribal placement of the group and the high incidence of brachyptery and reduced (or absent) ocelli in the group are discussed. A revised key to the Faltala group genera and additional characters for Kramerana are provided.

Copitarsia decolora (Guenée) is a widely distributed, highly polyphagous pest found throughout Central and South America. We examined multiple populations of C. decolora with the mitochondrial gene cytochrome oxidase I (COI). We also investigated morphological variation in adult males sampled from these populations. COI evidence suggests that C. decolora is comprised of two cryptic lineages and is paraphyletic with respect to the Chilean C. naenoides (Butler). These two lineages, which are not completely geographically isolated, display high divergence in COI sequences compared with other members of Copitarsia and other insect pest species in general. Furthermore, these lineages also possess slight morphological differences in male genitalia; however, supporting information is necessary before the taxonomy of this species is revised.

The genetic and geographical variation, gene flow, and the historical biogeography of the eastern lubber grasshopper, Romalea microptera (=guttata) (Houttuyn), were examined by sequencing a 420-bp region of the mitochondrial cytochrome b gene. Individuals (168) were collected from 12 sites in the southern United States that covered most of the range reported for this species. These populations contained 49 mitochondrial DNA haplotypes. A high level of genetic diversity was observed in these populations (3.8%), most of which was due to variation within populations. The highest genetic variation was found in a northern Florida population (collected at St. Marks, FL), and the lowest was found in a southern Florida population (Copeland, FL). Estimates of historical and current population sizes suggest that most of the lubber populations drastically declined in size at some point in the past. In contrast to previous studies on several other species in this region, phylogenetic analyses (PAUP) and haplotype age phylogenies (PHYLIP) showed no major geographic structure. These observations suggest that the distribution of this species in the past may have been homogeneous, rather than the patchy distribution that is currently observed. Alternatively, this result may reflect the absence of long-term barriers for the dispersal of this species. Either of these might have contributed to the lack of a genetic structure divided geographically into east-west groupings that is seen in other species from this region.

The Monterey pine aphid, Essigella californica Essig, is a recent incursion into Australia. Its sudden and rapid spread into commercial Pinus radiata D. Don plantations has caused concern to the forestry industry. Laboratory-based development studies showed that the apterous morph has three instars rather than the four typical of aphids. This difference was validated by an analysis of field-collected samples. The adaptive significance of this finding is discussed in relation to other aspects of this species’ life history.

This study attempts to estimate the influence of local environmental conditions on dung beetle assemblages in a bioclimatic transition area. Dung beetle assemblages were monitored by monthly dung-baited pitfall trapping from July to October at five sites in the Southern Alps (Verdon Valley). The sites were characterized by both elevation (≈1,000, 1,500, and 2,000 m a.s.l., respectively) and exposure (north/south). Exposure had a noteworthy influence. In summer, Coprinae showed by far the highest numbers and biomass in the sites facing south regardless of elevation. In the north-facing sites, Aphodiinae dominated the assemblages. In autumn, the abundance of Coprinae decreased and, in turn, Aphodiinae became dominant in most assemblages. Species composition changed with assemblage structure and dynamics. When Coprinae were numerous, few species were predominant in the assemblages and diversity was negatively related with elevation. In the Southern Alps, the alternate predominance observed between Coprinae and Aphodiinae species, which develop at distinct elevation ranges, is analogous to the supramediterranean vegetation range, which characterizes Mediterranean mountains.

We examined the nature of sibling egg cannibalism behavior and its developmental consequences in three aphidophagous Coccinellidae that all lay clustered eggs: Cycloneda sanguinea L., Harmonia axyridis (Pallas), and Olla v-nigrum Mulsant. There was variation among species in the proportion of eggs laid singly versus in clusters (C. sanguinea > H. axyridis ≈ O. v-nigrum), the synchrony of egg hatch within clusters (H. axyridis > C. sanguinea ≈ O. v-nigrum), and the proportion of eggs cannibalized by early-hatching larvae (O. v-nigrum > C. sanguinea > H. axyridis). Single eggs were cannibalized at lower rates than clustered eggs in all three species, and cannibals delayed dispersal from clusters until all unhatched eggs were consumed. In all three species, the number of eggs cannibalized was negatively correlated with the proportion hatching synchronously (within 10 min). Egg cannibals survived to adulthood at the same rate as noncannibal larvae in H. axyridis and O. v-nigrum, and at a higher rate in C. sanguinea. In all three species, larvae that cannibalized eggs as neonates molted to the second instar sooner than did their noncannibalizing counterparts, regardless of gender. This translated into reduced total developmental time for both sexes in H. axyridis, but only for males in C. sanguinea and only for females in O. v-nigrum. Adult females weighed significantly more than adult males in all three species and female cannibals were heavier as adults than were noncannibalizing females in H. axyridis and O. v-nigrum, whereas males had similar weights. Egg cannibalism had no effect on adult weight in C. sanguinea, but the rearing diet was not optimal for this species. We conclude that the benefits of sibling egg cannibalism accrue in a gender-specific manner such that females potentially gain more than males, but only if the subsequent larval diet is of sufficiently high quality.

Aedes albopictus has replaced Aedes aegypti in much of the latter species’ historic range within the United States. The leading hypothesis for this displacement is exclusion via resource competition; however, the proximate mechanism producing a competitive advantage for A. albopictus over A. aegypti has not been identified. We performed laboratory experiments to test the hypotheses that these species differ in feeding behavior, and that these differences result in differences in survival when resources are scarce. Differences in feeding behavior were assessed in three environments with food (growing microorganisms) available: 1) in fluid only; 2) on leaf surfaces only; 3) or both in fluid and on leaf surfaces. We determined behavior of larvae in these environments, recording their positions (bottom, wall, leaf, top, or middle) and activities (browsing, filtering, resting, or thrashing) using instantaneous scan censuses. A. albopictus spent significantly more time at leaf surfaces, whereas A. aegypti spent more time engaging in nonfeeding activities. Both species showed a significant shift in foraging activity toward leaves when leaves were available. In a second experiment, we recorded survivorship for individuals raised in two treatment combinations: whole or half 17-mm disks of live oak leaves, with or without direct access to the leaf surface (controlled using nylon mesh, which allowed movement of microscopic organisms, but prevented mosquito larva movement between container sides). After 31 d, survivorship of A. albopictus was significantly greater than that of A. aegypti regardless of treatments. Moreover, A. albopictus showed significantly greater survivorship compared with A. aegypti when deprived of access to leaf surfaces and in whole leaf disk treatments, suggesting superior resource-harvesting ability for A. albopictus. Our experiments suggest that differences in foraging behavior contribute to the competitive advantage of A. albopictus over A. aegypti that has been observed in North America.

Fertility life tables were developed for both Trichogramma pretiosum and Trichogramma acacioi reared on Sitotroga cerealella eggs as an alternative host at five different temperatures. The egg parasitoids were first collected from Nipteria panacea eggs, a lepidopterous pest of avocado. Egg parasitoid females were individualized in small glass vials along with 40 eggs of the host during 24 h for parasitization. For evaluation of the parasitism capacity, a similar procedure was adopted, but cardboards with eggs were replaced every day. The net reproductive rate (Ro), intrinsic rate of increase (rm), finite rate of increase (λ), and mean generation time (T) were estimated. Temperature affected all parameters for both Trichogramma species. The highest fecundity for both species was observed at 25°C. Extreme temperatures such as 15°C or 35°C negatively affect the development rate of both species.

We examined the population genetic structure of an extremely successful invasive wasp, Polistes dominulus. Although successful biological invasions of social insects have been associated with genetic bottlenecks, our research uncovered an unexpected level of genetic diversity in the northeastern U.S. invasion population. Compared with a previously studied European sample, the northeastern U.S. invasion population shows no significant reduction in gene diversity and no trace of a genetic bottleneck in the putative “introduction population.” We identified multiple private microsatellite alleles in both Massachusetts and New York, which strongly suggests that the northeastern U.S. P. dominulus population arose from at least two independent introductions. Although a genetic bottleneck may enhance invasion success for some social insects, genetic and geographical data on this successful invader suggest that this wasp may represent the converse. Our results support immediate identification of genetic diversity in an invasion population before the occurrence of secondary introductions as an essential part of managing and controlling invasive species.

We examined the scale of recruitment limitation in the western harvester ant, Pogonomyrmex occidentalis (Cresson). We measured colony density of 98 plots (0.25 ha) over an area of 500 ha. By applying an interpolation/extrapolation analysis to the spatial variability in colony density, we were able to accurately identify the location of two mating swarms. These two swarms were ≈1,400 m apart. Consequently, we conclude that if recruitment limitation generates variability in ecological processes such as density dependence, then variability should occur on the order of 1.5 km.

Ribosomal ITS2 DNA fragments were sequenced from four Peristenus species, two Leiophron species, and two Lygus species. Specific primers for polymerase chain reaction (PCR) amplification were designed from ITS2 DNA sequences to separate each species from the others. Using this molecular approach, we were able to determine whether Lygus hesperus Knight and Lygus lineolaris (Palisot de Beauvois) were parasitized by Peristenus and Leiophron parasitoids. The PCR technique was very sensitive and could detect Peristenus stygicus Loan DNA at a concentration of 0.01 pg/μl or 7.5 × 10⁻⁷ wasp DNA equivalents. Detection of P. stygicus eggs confirmed that early detection of parasitoids was possible. Parasitoid DNA was readily recovered from all L. hesperus nymphs that were parasitized by a single P. stygicus after 1 h of contact between the parasitoid and putative hosts. This study demonstrates the effectiveness of a molecular technique for detecting parasitoids developing inside their hosts.

Soon after swarming, the alates of the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), drop their wings, form tandem pairs, and look for new nesting sites to form incipient colonies. In ≈10% of the several hundred incipient colonies kept in laboratory, both the male and female were found to cannibalize their progeny and die of starvation. Examination of such adults revealed that all of them had lost most of their gut fauna, essential for the digestion of wood. We used antibiotic (gentamicin) and a combination of gentamicin and antiprotozoal (metronidazole) compounds during 2002 and 2003, respectively, to induce defaunation in 30-d-old adults after they had laid 30–40 eggs. The progeny of treated pairs compared with control pairs was significantly lower 30 and 60 d after treatment. Feeding on these chemicals during 2003 caused total loss of spirochetes and one of the three flagellates, while the numbers of the other two flagellates were greatly reduced. It is suggested that, in the absence of gut fauna, the adult termites cannot effectively feed on wood, and the ensuing hunger results in cannibalism of their progeny.

Mature colonies of the Formosan subterranean termite, Coptotermes formosanus Shiraki, like most other termite species, produce a reproductive caste in the form of nymphs that subsequently give rise to alates. Temporal production of nymphs in C. formosanus was monitored in monthly collections from four field traps in New Orleans, LA. Nymphs were present throughout the year with peak numbers observed during October/November and May. Large nymphs first occurred in December and peaked in March. Fewer than 1.5% workers formed nymphs within 3 months after collection from the field and after removal of the preexisting nymphs. Collections from other colonies, kept in the laboratory for >2 yr, did not produce any nymphs. It is speculated that a nymph induction factor (NIF), possibly coming from a mature physogastric queen, elicits nymph formation. The same or a similar factor may also be responsible for further development of nymphs and their transformation to alates. In the absence of this latter factor, the nymphs, except those in the most advanced stage of development, are either cannibalized or transform into brachypteroid neotenics. A scheme for the formation and transformation of various developmental stages within each caste of C. formosanus is presented.

We analyzed the life history characters related to rate of potential population growth for two genetically identical lines of Trichogramma kaykai Pinto and Stouthamer (Hymenoptera: Trichogrammatidae). These lines differed in that one was infected with parthenogenesis-inducing Wolbachia (W ), whereas the other was free of Wolbachia (W⁻) through antibiotic treatment. For both lines, the number of females emerging per day was the highest from eggs laid during the first 2 d of oviposition. Although adult longevity in W⁻ was shorter than that in W , number of eggs reaching the prepupal stage, adult emergence, and female emergence were significantly higher for W⁻ than for W . There were no significant differences in the number of mature ovarian eggs at emergence between W⁻ and W . The values of mean length of generation (T) in W was similar to that in W⁻, but the values of net reproduction rate (R₀) and intrinsic rate of natural increase (r_m) in W were lower than those in W⁻. In most field populations, the W individuals form a small percentage (<5%) of the total population. The relative low growth rate caused by the Wolbachia infection may contribute to this low prevalence of the infection. Because differences in the relative population growth rates would soon result in the extinction of the infected population in the field, other factors must play a role in allowing the infection to maintain itself in the field.

Biodiversity of Elateridae in three forest types, i.e., larch plantations (Larix kaempferi (Lamb.) Carrière), secondary forest, and primary forest, was investigated and compared. Click beetles were captured with malaise traps in 46 stands in three 14-d periods in June, July, and August. A total of 550 individuals, representing 53 species of click beetles, were captured for this study. The number of species and the number of individuals were not significantly different among the three forest types. However, the composition of species in the three forest types was different. The 46 stands were divided into three groups that were approximately equivalent to the three forest types by Twinspan analysis. Elaterid species associated with the primary forest was Dalopius exilis Kishii. Selatosomus puerilis Kishii and Hemicrepideus secessus secessus Candèze were specific to the secondary forest, and Hemicrepidius sinuatus sinuatus (Lewis) and Ampedus optabilis optabilis (Lewis) showed their preference for the larch plantation. In environmental factors investigated, openness of the canopy influenced the number of the species.

Venom from the endoparasitoid wasp Pimpla turionellae L. (Hymenoptera; Ichneumonidae) was isolated in pure form. Total protein determination indicated an average value of 0.04 μg protein per venom sac. The molecular weights of the venom components were estimated with reference to molecular weight markers and reference proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Analysis indicated that venom primarily contains proteins with molecular weights between 20 and 106 kDa. The presence of melittin and apamin in wasp venom was shown by SDS-PAGE and reversed-phase high-performance liquid chromatography (HPLC). Infrared spectroscopic data confirmed the acidic nature of the venom and the presence of amines, peptides, proteins, and enzymes in the venom. Venom noradrenaline was separated using thin-layer chromatography and verified by infrared spectroscopy.

Centrifugation increases the frequency of twin formation during embryogenesis in firebrat, Thermobia domestica (Packard). Newly hatched eggs of T. domestica were separated into control and experimental centrifugal groups. Double embryos were found among both groups at ≈0.1% naturally and ≈4.5% after centrifugation. Embryos with a double head and a third eye were also observed among the centrifuged eggs. The development of morphological and anatomical structures of twin embryos was compared with those of single embryos. The analysis was carried out by using light and electron (scanning and transmission) microscopy. Embryonic twins may help explain the mechanisms that lead to formation of germ bands in short germ-band insects, a group to which T. domestica belongs.

Singh-Pruthi (1925) defined the ejaculatory reservoir as “an expansion of the ejaculatory duct at the base of the vesica [=aedeagus] present in Heteroptera.” After carefully examining the external male genitalia of Dinidoridae, Scutelleridae, Tessaratomidae, and Cydnidae, we found that Singh-Pruthi’s definition could not be satisfactorily applied to the above-mentioned families. Therefore, it is necessary to redefine the ejaculatory reservoir in the Pentatomomorpha. We found that the structure protrudes from the dorsobasal portion of the expansion of the ejaculatory duct within the apical one-half of the aedeagus. We redefine that part of the structure outside the base of the aedeagus as the “ejaculatory reservoir” and the other part within the aedeagus, including the expanded ejaculatory duct, as the “reservoir lumen.” There are three differences between our definition and that of Singh-Pruthi for the ejaculatory reservoir: 1) the position (an evolutionary event) within the middle of the aedeagus versus at the base of the aedeagus, 2) the nature of the structure protruding from the expanded ejaculatory duct versus an expansion of the ejaculatory duct, and 3) the presence in only Pentatomomorpha versus in Heteroptera.

A study of the internal morphology of the alimentary canal of Chrysoperla rufilabris (Brumeister) adults in relation to yeast symbionts was conducted using light, scanning, and transmission electron and epifluorescence microscopy. The alimentary canal of field-collected adults possessed a single large (≈300–400 μm in length) diverticulum at the posterior end of the foregut. Although yeast cells (4.0–6.5 μm) were distributed throughout the alimentary canal, large numbers of blastically dividing cells (i.e., yeast) were observed within the diverticulum. The diverticulum interior was highly convoluted and folded transversely and longitudinally, and yeast cells were observed to accumulate within the folds. Large tracheal trunks were attached to the lateral side of the diverticulum, suggesting a high demand for gas exchange within this organ. The diverticulum was lined with cuticle, and the underlying tissues did not contain large amounts of endoplasmic reticulum, mitochondria, or Golgi complex, indicating that minimal absorption occurred within this gut region. This suggested that the high potential for gas exchange in the diverticulum by the tracheal trunks was primarily to support yeast metabolic activity. All size classes (i.e., 0.1, 4.0, and 10.0 μm) of fluorescence particles ingested by newly eclosed adults eventually ended up in the midgut and hindgut regions, indicating that the foregut and/or diverticulum do not possess an absolute mechanism for retaining particles based on size. However, all size classes of the fluorescent particles typically persisted within the diverticulum. The evident confluence between the diverticulum lumen and the gut lumen suggested a free exchange or flow of fluids between these regions. The proventriculus (proximal to the diverticulum) was pronounced and consisted of a series of long “hairs,” short “hairs,” and small spine-like structures projecting into the midgut. Large numbers of yeast cells were observed in association with the proventricular hairs, and these hairs may play a role in the retention of yeast cells. The midgut possessed typical absorptive structures (i.e., microvilli), and large numbers of mitochondria, rough endoplasmic reticulum, and Golgi complex were observed in midgut epithelial cells. Because evidence indicated no or minimal absorption of nutrients within the diverticulum, it was concluded that nutritional factors provided by the yeast must be transferred to the midgut where absorption occurs. Large numbers of yeast cells enclosed within a well-developed peritrophic matrix were observed in the midgut, suggesting that the yeast themselves may serve as a source of nutrients. Whereas the exact mechanism by which yeast contribute to the nutrition of C. rufilabris adults was not determined, morphological evidence obtained in this study supported the hypothesis that chrysopids form a mutualistic symbiosis with yeast and that the esophageal diverticulum was a specialized structure for housing them.

In the current study, inter-simple sequence repeat (ISSR) primers (p-13 and p-15) were used to estimate the population genetic structure of the sharpshooter Homalodisca coagulata (Say) (Homopera: Cicadellidae). Eighteen populations from throughout the United States and a population from Tahiti, French Polynesia, were analyzed. Populations were arbitrarily assigned to three regions: southeastern, southwestern, and western. Exact tests for population differentiation indicated highly significant differences in marker frequencies among the 18 populations with both primers. Analyses of molecular variance also indicated significant geographic structuring with both primers. A dendrogram based on Reynolds coancestry distance performed with p-15 clustered the U.S. populations into two main groups. The southeastern populations were grouped into one cluster and the southwestern and western populations into a second cluster. Within the western region, dendrograms produced with p-13 and p-15 showed in both cases that two populations (Edison and Bakersfield) clustered as outliers. The average divergence (D) among all populations was 0.099. Divergence values of 0.254, 0.103, and 0.102 were observed when comparing Bakersfield and the southeastern, southwestern, and western populations, respectively. Within the western region, D values for Bakersfield were 1.8- (p-13) and 2.4-fold (p-15) higher than the D of the western populations. The present results suggest that a subset of insects in California may have their origins in the southwestern region (Texas); furthermore, these results are suggestive of more than one founding event in California and/or biotypes or geographic races.

Darwin suggested that females should be more selective than males when choosing mates because eggs cost more than sperm, females mate fewer times, and females undergo most of the parental care. We studied sexual selection in a New Zealand leafroller, Cnephasia jactatana Walker, in relation to age, virginity, and body size in the laboratory. Results show that males significantly preferred young and virgin to old and mated females for mating, suggesting that the reproductive fitness of females depends strongly on their age and virginity. Female significant preference for virgin males regardless of male age indicates that male virginity and age have asymmetric effects on male reproductive fitness. Higher mating success in males with longer antennae, regardless of male body weight, suggests that male antennal length rather than body weight plays an important role in sexual selection. The similar antennal-wing length relationships between selected and nonselected males suggest that the absolute length of both antennae and wings are selected characters in male mating success. Males selected mates according to their own and their partners’ body weight but did not have significant preference for females’ antennal length and antennal/body length relationships, suggesting that body weight, rather than morphological features, plays a major role in female mating success. In the sexual selection of C. jactatana, males seem to be the choosier sex as a result of (1) females varying more in quality than males and (2) fertile spermatogenesis occurring exclusively during the pupal stage, potentially leading to sperm limitation.

The host quality model for explaining the sex ratio of progeny of hymenopterous parasitoids was tested with Anisopteromalus calandrae (Howard) parasitizing Sitophilus oryzae (L.). The life span of females and males did not show any influence of body size: 15.3 ± 6.14 and 15.9 ± 4.16 d for females of small and large size, and 5.4 ± 1.90 and 6.0 ± 2.30 for males. However the reproduction rate of large females was twice as high as for small females (80.9 ± 5.78 versus 37.4 ± 3.16). Large males mated with twice as many females as did small males (19.2 ± 3.8 versus 8.1 ± 3.8), suggesting that females do not gain greater fitness by being large than males. In a system in which the parasitoid was permitted to search among randomly dispersed host patches, large females showed a higher net reproduction rate than small females. This was not influenced by the size of male the females mated with: 132.8 ± 9.81 and 132.5 ± 7.41 for large females mated with large and small males, respectively, and 70.4 ± 13.72 and 54.07 ± 6.17 for small females mated with large and small males. The size-dependent dispersal ability among host patches of females, which is the active dispersal sex, is another factor that influenced oviposition behavior of A. calandrae, which assigns daughters on large hosts and sons on small hosts.

Previous work with the cryptic sister species pair of field crickets, Gryllus texensis Cade & Otte and Gryllus rubens Scudder, has implicated sexual selection in the speciation process. That study examined reproductive character displacement (RCD) in male song and female preference for song in G. texensis. No evidence of RCD was found. Here, we provide a similar analysis of RCD in G. rubens song and examine the songs of both species from areas of sympatry in an effort to document the species-specificity of song in sympatry and to look for individuals with songs indicative of F1 hybrid status. We 1) find no evidence for RCD in G. rubens song, 2) demonstrate the distinctness of song in sympatry, and 3) document the rarity of songs typical of F1 hybrids.

We analyzed the probing (stylet penetration) behaviors of the sharpshooter leafhopper Graphocephala atropunctata (Signoret) on grape with an alternating current (AC) electrical penetration graph (EPG) monitor. We characterized waveforms likely to represent stylet penetration pathway phase and xylem ingestion. The total probing duration of the cohort represented 68% of all 20-h monitoring periods for all insects, yet only a small proportion of that probing time was spent in high amplitude/pathway activities. Few changes in behavior occurred once a probe had started. This was shown by the low number of waveform events (i.e., uninterrupted occurrences of a behavior) per probe for each waveform type, which varied from a mean of 1–2.43. Conditional probability analysis supported that hypothesis, because insects usually terminated a probe and began a new one after ingestion-related events, rather than repeating in the same probe the previously performed waveforms. The size of grape leaves used for the assays directly influenced the amount of time insects ingested from xylem or performed other low-amplitude waveforms. Information from this work establishes benchmarks for future research addressing the mechanisms of Xylella fastidiosa Wells et al. transmission and sharpshooter ecology.

The Bemisia tabaci (Gennadius) complex contains the only known whitefly vector of plant-infecting begomoviruses, which are the causal agents of mosaic diseases of cassava in Africa and India. Widespread phenotypic variability, together with the absence of definitive morphological taxonomic characters for this whitefly complex, has confounded both the systematics and the study of its virus vector biology. Substantial genetic variability and phylogeographical relationships have been shown for phenotypic, but morphologically identical, variants of B. tabaci based on the mitochondrial (mt) cytochrome oxidase I (COI) sequence, leading to the suggestion that they represent a species complex. Here, phylogenetic relationships were explored, using the mtCOI sequence (780 bp) as a molecular marker, for B. tabaci collected from cassava plants in southern and western Africa, including Cameroon, Zambia, Mozambique, Zimbabwe, Swaziland, and South Africa. Maximum likelihood analyses of mtCOI sequences revealed that most B. tabaci examined were placed into one of three subgroups within the major sub-Saharan African clade, which also contains previously reported populations indigenous to Malawi and Uganda, and collectively shared on overall nucleotide (nt) identity at 88.9–99.7%. Two other reference populations, the monophagous Benin haplotype from Asystasia spp. and a B. tabaci from cassava in the Ivory Coast (IC), were the most divergent outliers of the sub-Saharan clade, each representing the only member of their respective clade (I and V), at the present time. Members of the sub-Saharan clade associated with cassava had as their closest relatives haplotypes I and II of the Mediterranean-Northern Africa clade, with which they shared a collective 84.2–92.9% nt identity (not including the IC cassava reference haplotype). In contrast, the sub-Saharan African clade diverged from the Americas and Southeast Asia/Far East clades at 79.7–85.1 and 77.5–84.9%, respectively. Within the sub-Saharan clade, subclade II contained B. tabaci from Zambia, Mozambique, South Africa, and Swaziland at 95–99% identity. The sub-Saharan subcluster III contained haplotypes from southern and western Africa. Counter to the otherwise phylogeographical relationships observed for cassava-associated B. tabaci from southern Africa, one and two populations from Cameroon (okra) and Zimbabwe (cassava), respectively, grouped with the major Mediterranean-North Africa clade, together with their closest relative associated with okra from IC, are included here as a reference sequence for the first time, with which they collectively formed a new, third subclade. Thus, phylogenetic analysis of B. tabaci mtCOI haplotypes examined thus far from the African continent has revealed five major cassava-associated haplotypes, which grouped primarily based on extant geography, with the exception of one and two collections from Cameroon and Zimbabwe, respectively. Hypotheses explaining the potential distributions of haplotypes are discussed.

In this study, we tested for the presence and efficacy of hygienic behavior by Cape honey bees in South Africa and European honey bees, Apis mellifera L. (Hymenoptera: Apidae), of mixed origin in the United States toward Aethina tumida Murray (Coleoptera: Nitidulidae) eggs oviposited in sealed bee brood. We looked for colony differences in removal rates of brood in cells with cappings perforated by A. tumida within each subspecies to identify colonies within location that display superior hygienic behavior. Finally, we determined the oviposition rate (number of A. tumida-perforated cells actually oviposited in by A. tumida/total number of A. tumida-perforated cells) in A. tumida-perforated cells and the number of A. tumida eggs oviposited in each cell. There were no colony differences within subspecies for the removal of normal capped brood, artificially perforated brood (capped cells perforated by experimenter with a pin), and A. tumida-perforated brood. For both subspecies, the bees removed significantly more A. tumida-perforated brood than either normal or artificially perforated brood. A. tumida oviposited significantly more eggs per cell in Cape colonies than in European colonies, but the oviposition rate in A. tumida-perforated cells did not differ between Cape and European colonies. Both subspecies removed a proportion of A. tumida-perforated brood statistically indistinguishable from the proportion of A. tumida-perforated brood containing A. tumida eggs. Thus, both Cape and European A. mellifera preferentially remove the contents of A. tumida-perforated cells in which A. tumida have actually oviposited.