The Tarsonemus minimax species-group is established for bark beetle commensals of the genus Tarsonemus Canestrini and Fanzago, 1876. T. minimax Vitzthum 1926 is redescribed, and two new species, T. terebrans and T. typographi n. spp., are described and illustrated. A diagnostic key to the species is supplied. The systematic status of the species-group is discussed. Biogeography and associations with insect hosts and fungi are reviewed.

The genus Pandivirilia is widespread across the Nearctic and Palaearctic regions. The Nearctic species are redescribed, including the description of two new species: Pandivirilia constricta Webb and P. rufa Webb. Their phylogenetic position among the Palaearctic species and related higher therevine genera is elucidated by cladistic analysis of male and female morphological characters. A key to the Nearctic species is provided along with maps of their distribution. A neotype is designated for P. albifrons (Say) and a lectotype is designated for Psilocephala limata Coquillett. Also, Dichoglena melampodia (Loew), Ps. conspicua (Walker), and Spiriverpa nitoris (Coquillett) are placed as new combinations within Pandivirilia. P. bussi (James) is placed as a new combination within Cliorismia, making this genus Holarctic in distribution. Ps. canadensis Cole, Ps. limata Coquillett, and Ps. pollinosa Cole are placed in synonomy under P. conspicua (Walker), P. argentifrons Cole is placed in synonomy under P. melampodia (Loew), and Thereva borealis Cole is placed in synonomy under P. albifrons (Say).

Nepalomyia Hollis and Neurigonella Robinson are synonymized. The genus Nepalomyia is more fully characterized and the Nearctic species are revised. Nepalomyia nigricornis (Van Duzee) and N. sombrea (Harmston & Knowlton) are reassigned and redescribed. Two new species, N. dilaticosta Runyon & Hurley and N. hesperia Runyon & Hurley, are described. New combinations are created for the following non-Nearctic species: Nepalomyia bidentata (Yang & Saigusa), N. brevifurcata (Yang & Saigusa), N. crassata (Yang & Saigusa), N. daliensis (Yang & Saigusa), N. daweishana (Yang & Saigusa), N. dentata (Yang & Saigusa), N. flava (Yang & Saigusa), N. furcata (Yang & Saigusa), N. henanensis (Yang, Yang, & Li), N. longa (Yang & Saigusa), N. longiseta (Yang & Saigusa), N. luteipleurata (Yang & Saigusa), N. pallipes (Yang & Saigusa), N. pallipilosa (Yang & Saigusa), N. pilifera (Yang & Saigusa), N. pingbiana (Yang & Saigusa), N. tatjanae (Negrobov), N. trifurcata (Yang & Saigusa), N. tuberculosa (Yang & Saigusa), N. yunnanensis (Yang & Saigusa), and N. zhouzhiensis (Yang & Saigusa). A key to Nearctic males and females and a catalog of the world Nepalomyia are provided.

We describe a new genus of anomaline scarab, Anomalorhina (Coleoptera: Scarabaeidae: Rutelinae: Anomalini) from Costa Rica and Nicaragua. Anomala turrialbana Ohaus is transferred into this genus, and a new species, Anomalorhina osaensis, is described. Anomalorhina is characterized by the clypeal apex that is abruptly reflexed, the base of the frons that has prominent tubercles in males, the pronotum with a depressed fovea in males, and the pronotum with the apical bead posteriorly produced and V-shaped at the middle in females. We summarize the biological importance of the 16 genera of New World anomaline scarabs, including comments on agricultural pests, larvae, and natural history. We provide an overview and synopsis of each of the New World anomaline genera with comments on biology and characteristics for identification.

Since 1934, the rotundifolia complex of Amblycorypha has consisted of two named species: Amblycorypha parvipennis Stal, occurring from the Mississippi River westward into the eastern edges of the Great Plains, and Amblycorypha rotundifolia, occurring in most of the eastern United States. The latter entity is here shown to consist of at least three species with distinctive calling songs and different but overlapping geographical distributions. At 25°C, A. rotundifolia (Scudder) produces ≈26 calling song units (phonatomes) per s, whereas Amblycorypha bartrami n. sp. Walker, A. parvipennis, and Amblycorypha alexanderi n. sp. Walker produce ≈10, 5, and 2.8 ph/s respectively. Amblycorypha rotundifolia occurs from Illinois to New York and southward along the Appalachians to northern Georgia. Amblycorypha bartrami occurs in the southeastern states, and A. alexanderi broadly overlaps the distributions of the other two eastern species. Where A. alexanderi and A. rotundifolia are sympatric, the two occur in similar habitats; where A. alexanderi and A. bartrami are sympatric, A. bartrami occurs in more xeric habitats. No morphological characters were found that reliably identify the three eastern species, yet no fewer than three species must be recognized to provide names for populations that behave as distinct species where they co-occur.

The first records for Brazil of two sciarid species, Bradysia difformis Frey, 1948 [= paupera (Tuomikoski, 1960)] and Bradysia ocellaris (Comstock, 1882) [= tritici (Coquillett, 1895)] (Diptera, Sciaridae) are presented. These are the first records of these species for the Neotropical region. Males and females of both species are fully described and illustrated. Information is given about synonymy and the location of the type material. Bradysia agrestis Sasakawa, 1978 is a new synonym of Bradysia difformis. Information about the zoogeographic distribution and habitats, of Bradysia difformis and Bradysia ocellaris is provided.

The larva and/or puparium of the Neotropical syrphids Habromyia coeruleithorax Williston, 1888, Palpada furcata (Wiedemann, 1819), and six species of Meromacrus Rondani, 1848, are figured, described, and compared with other similar larvae. All of these larvae are similar in external form, having mouthparts adapted for filtering suspended items of food, retractile anterior spiracles, prolegs with crochets, and extended anal segments (=long-tailed larvae). Each species varied in the size and distribution of integumental setae and spicules and in the size and form of the pupal spiracles. Keys are provided to identify genera of Neotropical long-tailed syrphid larvae and to separate the six species of Meromacrus: M. acutus (Fabricius, 1805), M. currani Hull, 1942, M. draco Hull, 1942, M. laconicus (Walker, 1852), M. loewii (Williston, 1892), and M. obscurus Hine, 1924. Larvae of all these species were found in tree holes, except for M. draco, which was associated with decaying bananas, and P. furcata, which occurred in a waste heap of decaying coffee pulp.

Many of the adult features that are considered diagnostic for Chrysopodes occur in other New World chrysopid genera; a stable and phylogenetically significant generic classification requires additional definitive characters. The current study demonstrates a number of morphological characters in the larvae that provide strong evidence for the validity of the genus and also provide a foundation for broadening and refining the definition of the genus. For example, the absence of a gonapsis no longer serves as a diagnostic character for Chrysopodes. Moreover, based primarily on larval characteristics but also on adult features, the widely distributed Nearctic species Ceraeochrysa placita (Banks) is now transferred to Chrysopodes. Finally, the manuscript reviews the systematics of the two Chrysopodes species reported from the United States; the adults are characterized and illustrated, the larvae are described, and biological data are presented.

Molecular phylogenetic methods were used to examine a number of morphologically based hypotheses concerning the taxonomic relationships and origin of the grasshopper subfamily Melanoplinae. This paper focuses on several North American genera and their interrelationships and connections with taxa on other continents. Portions of four mitochondrial genes (coding for cytochrome b, cytochrome oxidase subunits I and II, and NADH dehydrogenase subunit II) were sequenced in 17 North American species representing 13 genera, along with five and eight species from South America and Eurasia, respectively. Phylogenetic trees were constructed using maximum parsimony, weighted parsimony, neighbor-joining, and maximum likelihood methods. Bootstrap replications provided levels of confidence for recovered associations. Maximum resolution was achieved using weighted parsimony and by treating all sequences, totaling 1716 bp, as a unit. In terms of taxonomic organization, our phylogenetic analysis demonstrated that an earlier division of Melanoplinae into two tribes, Melanoplini and Podismini, has merit. Monophyly of each tribe was supported statistically. There was, however, no support for various systems subdividing Podismini into subtribes or “groups.” Neither eastern nor western North American podismines proved monophyletic. There was no support for the integrity of another proposed tribe, Dactylotini. All methods suggested South America as the place of origin for the subfamily, supporting previous molecular studies. Both tribes originated in North America, most probably in the southwest United States. With respect to Podismini, this is contrary to the prevailing view of a Eurasian origin for the tribe.

The migratory locust, Locusta migratoria L., shows phase polymorphism in which various morphological, physiological, and behavioral traits change according to population density. Information about the reproductive behavior, particularly sperm competition and male-female associations, has been obtained mainly from crowd-reared locusts. To understand the reproductive strategy in different phases, i.e., solitarious versus gregarious phase, we compared the P₂ (i.e., the proportion of offspring sired by the second male to mate), length of pre- and postcopulatory mounting and length of copulation between solitarious (isolated-reared) and gregarious (crowd-reared) adults of this locust. We observed that solitarious adults had a higher P₂ value, shorter precopulatory mounting, and longer copulation than gregarious adults. A significant positive correlation between length of precopulatory mounting and copulation was found in gregarious adults, but not in solitarious adults in the two geographic strains used. Little or no postcopulatory mounting was observed in either phase. Pairing of crowd-reared males and isolated-reared females indicated that males did not play a decisive role in determining these behaviors. The results demonstrate phase-related differences in reproductive strategy that are likely to be adaptive for locusts facing a large variation in chance of encounters between the two sexes.

I quantitatively analyzed male morphology of two closely related stag beetles species (Odontolabis mouhoti Hope and O. cuvera Parry) in 11 allopatric and two sympatric locations in the Asian tropics and subtropics. Across allopatric locations, body size and genitalia size nearly completely overlapped between O. mouhoti and O. cuvera, and body color was more similar between the two species in allopatric locations. In sympatric locations the differences between the two species in these characters were highly noticeable, genitalia size being most significant. The body color difference between the two species was most striking in sympatric locations. It is probable that the interaction between the two species induced character displacement in sympatry. Character displacement may enable species to maintain themselves as integrated units by minimizing interspecific competition and enhancing reproductive isolation.

Aedes albopictus became established in Brazil and the USA during the same approximate period of the mid-1980s and spread rapidly in both countries in succeeding years. Early populations in the USA, believed derived from temperate Japan, all possessed a photoperiodically inducible egg diapause, but a population from Brazil, of probable tropical origins, did not. Based on responses of geographic populations to a common short (10L:14D) day length, we demonstrate that the spread of A. albopictus in Florida from more temperate USA has been associated with a gradual loss of diapause, such that diapause incidence is now positively correlated with latitude in the southern USA. In Brazil, most populations tested 15 yr after the initial invasion show no evidence of diapause, except for three from the two southernmost states (>26°S), in which a small, but significant percentage of eggs from mothers exposed to short day lengths were dormant. Diapause reduction in the southern USA and diapause acquisition by A. albopictus in southern Brazil have not resulted in similar response levels at comparable latitudes in the two countries, in part because of genetic constraints of different founder populations from temperate and tropical origins and different selective regimes in the two invaded countries.

Despite great variation in instar number among Insecta, no Lepidopteran has been observed to have less than four larval instars. I report in this work on the life cycle and growth of the senita moth, Upiga virescens Hulst, which forms an obligate pollinating predispersal seed-eating mutualism with senita cacti (Lophocereus schottii Engelmann) in the Sonoran Desert of North America. From 1996 to 1999, I studied larval growth and life cycle associations of U. virescens with L. schottii in the field by labeling cohorts of eggs laid in flowers and following them through pupation. All life stages of U. virescens were associated with flowers, fruit, or cactus stems of L. schottii. Among the five cohorts studied, larval growth consistently conformed to Dyar’s rule. Only three larval instars were identified among the >500 larvae for which head capsule widths were measured. I discuss and dismiss the feasibility of a fourth undetected instar. I then discuss selection pressures that may have contributed to the evolutionary loss of an instar, including a time and/or size constraint on larval growth, as well as the nutritional quantity and quality of larval food.

The Indianmeal moth, Plodia interpunctella, is a serious pest on dried fruit and oil-rich food products, such as pet food, cereals, flour products, and candy bars. We examined the P. interpunctella oviposition on unscreened food dishes with whole-wheat kernels treated with one of 18 different oils diluted in hexane (oil-treated) compared with a second unscreened food dish with whole-wheat kernels treated with hexane only (control). For eight of the 18 oils, the same two-choice experiment was conducted with screened food dishes. We concluded that (1) total oviposition was significantly lower when food dishes were screened compared with experiments with unscreened dishes; (2) using unscreened food dishes, P. interpunctella females laid significantly more eggs in 17 types of oil-treated wheat compared with dishes with control wheat kernels; and (3) using screened food dishes, P. interpunctella females only laid significantly more eggs in walnut oil-treated wheat compared with dishes with control wheat kernels. A nine-choice experiment was conducted in a large arena with unscreened food dishes, in which one dish contained control wheat kernels and eight other food dishes contained wheat treated with different oils. In the nine-choice experiment, P. interpunctella females showed the strongest response to wheat kernels treated with oil from walnut. This study provides the basis for chemical identification of oviposition stimulants for P. interpunctella from food oils.

The spatial distribution of the waterscorpion Ranatra nigra Herrich-Schaeffer (Hemiptera: Nepidae) in the Mobile/Tensaw Delta, Mobile, Alabama, was examined. Twenty-seven sites were sampled once in the fall (10–16 October 2001) and again the following spring (22 May-5 June 2001). A principal component analysis in combination with logistic (presence/absence) and stepwise (abundance) regression was used to associate the distribution of R. nigra with select abiotic variables (pH, conductivity, temperature, oxygen, stream width, GPS coordinates). Both the occurrence (presence/absence) and abundance of R. nigra were significantly (P < 0.001) associated with GPS coordinates, i.e., it was most common closer to the Mobile Bay than further into the Delta. In addition, R. nigra was more likely to occur in smaller, cooler streams, with lower oxygen and pH levels and higher conductivity. The prevalence (percentage of infected host) and abundance (number of mites/infected host) of the parasitic mite Hydrachna magniscutata (sensu latu) Marshall on R. nigra were also examined. The proportion of R. nigra with mites was highest in the fall and lowest in the spring (P < 0.001), but the number of mites per host did not change (P > 0.05) with time.

The Madeira mealybug, Phenacoccus madeirensis Green (Hemiptera: Pseudococcidae), has become an increasingly damaging pest in greenhouse ornamental production. Current management tactics of P. madeirensis require a regular chemical application schedule targeting the immature stages. Knowledge of the life cycle of P. madeirensis is important to the success of its management program. We investigated the effects of constant temperature (15, 20, 25, 30, 35, and 40°C) on the development, survival, and reproduction of P. madeirensis on chrysanthemum (Dendrathema x grandiflora Kitam.). We failed to establish colonies at 30–40°C. Between 15 and 25°C, the duration of development of all developmental stages were shortened at higher temperatures. The total duration of development of female mealybugs was ≈30 d at 25°C, 46 d at 20°C, and 66 d at 15°C. Developmental time of males was 3–9 d longer than females. Survival rates of individual instars ranged between 88 and 100% and were not influenced by temperature. Overall, >75% of eggs completed development to adulthood. Female mealybugs made up 50% of the adult populations in all temperature treatments. Adult longevity at 25°C was ≈3 and 20 d for males and ovipositing females, respectively. Females at 20°C produced the highest number of eggs (491 ± 38 eggs/female).

The molecular size limitations of the digestive system, including the filter chamber of immature and adult Bemisia tabaci (Gennadius) B biotype (=B. argentifolii), were studied by tracking the movement of fluorescent-labeled molecules and microspheres ingested by whiteflies. Soluble fluorescent molecules and labeled dextrans, ranging from 389 to 2,000,000 Da, were observed throughout the digestive tract of immatures 10–30 min after feeding was initiated. After removal of labeled molecules from the diet, fluorochromes were cleared from digestive system of immatures within 2 h. Fluorescent-labeled 0.1- and 0.2-μm microspheres were ingested by larvae and saturated the digestive system within 2 h after initiation of feeding. Large, 0.5-μm spheres were not observed in the digestive tract of immatures, probably because singly or as aggregates, they were too large to enter the stylet food canal. The smallest spheres examined, 0.02 μm, were not detectable in the digestive tract of immatures. Observations for whitefly adults were identical to those for larvae, with two exceptions. In adults, soluble fluorochromes were detectable1 h after feeding commenced, and 0.02-μm spheres were observed primarily in the esophagus, filter chamber, anterior midgut, and hindgut, but not in the posterior portions of the midgut. We hypothesize that most of the 0.02-μm spheres ingested by adult whiteflies were shunted directly to the hindgut by way of the filter chamber, effectively bypassing the midgut. This is, therefore, a feasible route for virions of the plant pathogenic genus Begomovirus, which are of similar size to the small microspheres and are transmitted in a circulative manner by B. tabaci.

Male-biased sex ratios in populations of parasitic wasps used in biological control are undesirable, because a low proportion of females can prevent the establishment of introduced species or hinder commercial production of species used for augmentative control. Studies were conducted on potential factors contributing to male-biased sex ratios that have been encountered in laboratory rearings of the braconid endoparasitoid Glyptapanteles flavicoxis (Marsh) using the gypsy moth, Lymantria dispar (L.), as a host. Sex determination in this wasp is arrhenotokous (haplodiploid). In the first experiment, we stored adults at 13 or 16°C and allowed them to mate at 20 or 25°C and found that sex ratios (expressed as percentage females) did not differ among progeny of parents; many females produced all male progeny, suggesting that they had not been fertilized. In the second experiment, females were exposed to hosts soon (0–60 min) after mating or 23–25 h later. Sex ratios were higher (less male-biased) in progenies of females provided with the rest period than in those which were not. In a third experiment, females were allowed to mate from one to four times with a given male. Although differences between these groupings were not statistically significant, the data suggested that more than two matings might depress sex ratios of progeny. An alternative analysis with only two groupings (1–2 matings and 3–4 matings) suggested that more than two matings might increase male bias of progeny. Therefore, we suggest that matings of this species be monitored in sleeve cages so that paired females can be removed and separated after copulation to diminish the likelihood of excessive matings, then given a rest period before they are offered hosts for parasitization.

Protandry in 11 stonefly (Plecoptera) species (representing five families) from Sierra Nevada (Spain) has been studied (recorded and quantified) over their flight period. All species exhibited a positive protandry coefficient (range, 0.07–0.33), indicating that no species shows proteroginy. Protandry was less pronounced in species having extended flight periods, brief flight periods, or highly concentrated flight maximums. The degree of protandry did not correlated with the degree of sexual dimorphism in size, contradicting the theoretical prediction of increased dimorphism with increased protandry.

The remating behavior of wild Ceratitis capitata (Wiedemann) females was examined after first mating to males from the wild or from one of two genetic sexing strains: Cast 191 (irradiated or nonirradiated males) or Seib 6-96 (irradiated males only). The observations were carried out in field cages set over a rooted host tree during a continuous period of 10 h in which females were individually identified. On average, 12% of females remated. The general trend was a higher rate of remating for females first mated with lab males compared with females first mated with wild males. It was observed that females that remated tended to start and end their first mating earlier than those females that did not remate, and the first mating of the former was shorter than that of the latter. However, there was no significant differences in copula duration between remater and nonremater females. Females mated initially to wild males showed the longest average refractory period and females mated to Cast 191 irradiated males the shortest. Females first mated to Cast 191 nonirradiated and Seib 6-96 irradiated males showed intermediate values. It is expected that the methodology used in this study can prove useful for routine quality control tests in medfly mass-rearing facilities.

We investigated the effects of indirect host stimuli (host fruit and host adult fly residues), direct host stimuli (oviposition), food supply (honey), and mating status on egg maturation of the synovigenic parasitoid, Fopius arisanus (Sonan), a highly successful biological control agent that attacks eggs of many tephritid fly pests. Female wasps normally reach a peak of mature egg-load on 4–6 d posteclosion. When providing female wasps with honey, access to these indirect host stimuli or males for 3 d after eclosion did not significantly increase the mature egg-load of the parasitoid on the fourth and sixth day posteclosion compared with the control treatment. When deprived of honey and housed with males, females that had access to indirect host stimuli during the first 3 d after emergence had a significantly higher egg-load on the sixth day than those denied access to direct or indirect host stimuli. The act of oviposition significantly increased the rate of egg maturation and minimized resorption in both the young and 6- to 7-d-old female wasps, regardless of honey supply. However, resorption of eggs by females did not increase their longevity, even when they were deprived of honey. Our results suggest that the effect of indirect host stimuli on egg maturation in this parasitoid is relatively subtle compared with the effect of oviposition and is not easy to detect because of the larger effects of oviposition and possible interaction with factors such as food supply.

To elucidate how ants use two simultaneously present food resources, honeydew and extrafloral nectary (EFN), in relation to aphid density, we first examined ant recruitment patterns with different densities of aphids on Vicia faba L. (Leguminosae) with EFN in two field sites with different species composition of ants. Three species of ants visited plants of V. faba at each site, but two different species, Tetramorium caespitum Linnaeus (Hymenoptera: Formicidae) and Lasius niger L. (Hymenoptera: Formicidae) were the main visitors on plants of V. faba at the different sites. The numbers of ants of T. caespitum and L. niger visiting a plant increased as the density of Aphis craccivora Koch (Homoptera: Aphididae) per plant increased. The correlation between the numbers of L. niger and Aphis craccivora was higher than that between the numbers of T. caespitum and A. craccivora. Second, we examined in a laboratory how two ant species, T. caespitum and L. niger, use the honeydew of A. craccivora and V. faba’s EFN. As the aphid density per plant increased, the numbers of ants of T. caespitum and L. niger using honeydew increased, and conversely, those using extrafloral nectar decreased. This study showed that ants shifted their collection pattern from extrafloral nectar to honeydew at higher density of aphids per plant, and it may be considered that honeydew is more attractive for ants than EFN at higher aphid density, because ants react sensitively to differences in the quality and/or quantity of both extrafloral nectar and honeydew.

Bioassays examining aggression in termites have typically been performed by pairing groups of workers from different colonies. We examined whether similar results would be observed using bioassays with individual workers. We report the results of pairings of individual workers of Reticulitermes spp. of three different hydrocarbon phenotypes (CA-A, CA-B, and CA-C). Resulting agonistic behavior between individuals can be used to infer relatedness of workers from different foraging groups because identification of species of Reticulitermes is often difficult. Pairings consisted of two termites from the same colony or from different colonies with the same or different phenotypes. We recorded avoidance behavior and immediate aggression during 5-min observations and mortality at 24 h. Intercolonial/intraphenotype pairings paralleled group bioassays with low levels of immediate aggression; however, individual pairings had lower levels of mortality at 24 h. Bioassays using individual Reticulitermes spp. workers in interphenotype pairings yielded results comparable with previously reported group bioassays and could be used in lieu of group bioassays. However, if immediate aggression is lacking, it would be advisable to use group bioassays or increase the number of replications to differentiate intracolonial and intercolonial pairings. Survival rates were the same for all phenotypes when paired with either of the other two phenotypes. There were, however, significant differences in the number of avoidance responses; pairings with CA-C had the highest number of avoidance responses followed by pairings with CA-B and CA-A. There were significant differences in immediate aggression; CA-C was the most aggressive, followed by CA-B and CA-A. Different levels of aggression among phenotypes provide additional evidence that these phenotypes represent distinct taxa or species.