A polymerase chain reaction (PCR)-based restriction fragment-length polymorphism (RFLP) assay was developed that discriminates among the 4 mitotypes found in North, Central, and South American honey bee racial groups—eastern European (Apis mellifera ligustica Spinola, caucasica Gorbachev, and carnica Pollman), western European (A. m. mellifera Linnaeus), Egyptian (A. m. lamarckii Cockerell Lepeletier), and sub-Saharan African (A. m. scutellata). Before the development of this assay, 13% of southern Californian feral bees collected before the arrival of the Apis mellifera scutellata (Africanized) race were found to contain a non-European mitochondrial genotype that could not be distinguished from that of A. m. scutellata. DNA sequence analysis suggests the unusual mitotype to be that of A. m. lamarckii. An RFLP polymorphism was identified that distinguished this subspecies from all others present in North America. This polymorphism was not found in any of 96 bees collected primarily in Mexico and Central America. Thus, the Egyptian mitochondrial type is either absent or extremely rare in these regions. The PCR assay also distinguishes A. m. lamarckii from 2 other north African racial types, A. m. intermissa Buttel-Reepen and A. m. sahariensis Baldensperger.

Two new species of podapolipid mites, Dorsipes tefflii and D. auncinius, are described, illustrated, and compared with related species of Dorsipes in the platysmae group. Both species are ectoparasites of Tefflus zebulianus reichardi Kolbe collected in the Democratic Republic of the Congo. These are the 1st records of Dorsipes in Africa. Keys to the ten species of Dorsipes are provided.

Exeretonevra Macquart is a small genus of flies (Diptera) belonging to the suborder Brachycera endemic to Australia. The classification of Exeretonevra has been extremely unstable; the genus has been placed in 3 of the 4 brachyceran infraorders at various times since it was described in 1846. Misplacements were a result of reliance on convergent characters of wing venation or plesiomorphic features of the adult. Synapomorphies critical to the classification of Exeretonevra remained unavailable for 150 yr because the larval stages were unknown. Here we describe egg and larval morphology of Exeretonevra angustifrons Hardy, and provide biological information on these life history stages. We also provide a detailed treatment of external anatomy of the adult and describe some aspects of adult biology. Larval characteristics and reinterpretation of adult morphology clearly show that Exeretonevra belongs to the family Xylophagidae, subfamily Coenomyiinae. A scanning electron microscope study of the paired bare areas present posterolaterally on the first abdominal tergite suggests that these areas are associated with, and provide an outlet for, a glandular product. The Xylophagidae is the sole member of the infraorder Xylophagomorpha, which are predominantly distributed in the northern hemisphere. Exeretonevra is the only Australian representative of this infraorder, and this lineage is likely to have existed on the continent since the Mesozoic. The distribution of larval habitats across xylophagid genera suggests at least 2 evolutionary transitions in the family between soil and rotting wood.

Nishihygia Brailovsky, n. genus, and 1 new species, N. hartzellae Brailovsky, collected in New Guinea, are described. The relationship with Missimhygia Brailovsky is discussed. Dorsal habitus illustrations and drawings of the female genital plates are provided.

Genetic variation was assessed for the closely related aphids Myzus nicotianae Blackman and Myzus persicae (Sulzer), previously classified as a single species. Populations of both red and green color morphs, collected from tobacco and nontobacco hosts from 3 continents, were analyzed via random amplified polymorphic DNA (RAPD)-polymerase chain reaction (PCR) and mitochondrial cytochrome oxidase II (COII) and elongation factor- 1 alpha (EF-1α) gene sequencing. Three other Myzus species—M. cerasi (F.), M. hemerocallis Takahashi, and M. varians Davidson)—were used as outgroups in our analyses. RAPD-PCR analysis revealed many, easily detectable genetic polymorphisms between the Myzus persicae complex and the outgroup species. The small number of polymorphisms detected within the complex were not correlated with host plant or the geographic origin of populations. The sequences of both COII and EF-1α for all populations within the M. persicae complex were identical, although significant variation was evident between the M. persicae complex and outgroup taxa. These results strongly suggest the synonymy of M. persicae and M. nicotianae.

The functional response and the effect of superparasitism of Diachasmimorpha longicaudata (Ashmead) in larvae of Anastrepha ludens (Loew) was determined under laboratory conditions. Adult parasitoids were tested individually and in groups of 5. Third-instar A. ludens larvae were exposed for 3 h to experienced, 5-d-old females at the ratios of 1, 5, 20, 30, 40, 50, and 60 host larvae per wasp. For individual females, functional response was type III, whereas for females in groups, a type II curve was observed. In the presence of conspecifics, females increased their parasitization activity. Females showed a strong tendency for self-superparasitism (the same female laying >1 egg in the same host) with a range of 38.9–57.9% of larvae superparasitized, even when there was no competition and a high availability of host larvae. In the superparasitism experiment, when the parasitoid/host ratio was 1 or greater, larval mortality was consistently high but never exceeded 90%. Successful parasitoid emergence decreased as the parasitoid/host ratio increased. We discuss and question the detrimental effects that have been attributed to superparasitism in solitary endoparasitoids.

Development of immature Mexican corn rootworm, Diabrotica virgifera zeae Krysan & Smith, was investigated at 8 temperatures ranging from 15 to 33°C. Development to adult was only completed in the range from 15 to 30°C; larvae failed to complete the 3rd instar at 31.5 and 33°C. Development from hatch to adult emergence was fastest at 30°C (≈25 d), and slowest at 15°C (≈105 d). Developmental times, from hatch to adult emergence, differed for males and females, males emerged before females. A pooled thermal threshold of 10.3°C was estimated for immature development. Development from hatch to adult emergence was estimated to take 473 DD.

Development in Marmara arbutiella Busck is hypermetamorphic, with 3 behaviorally and morphologically distinct larval forms. There are 6–8 sap-feeding and 2 nonfeeding, structurally differentiated instars. The early instars are legless, dorsoventrally compressed, prognathous sap feeders. The 1st of the nonfeeding instars, which we call the transition instar, never issues from the cuticle of the previous (feeding) instar; instead there is apolysis without ecdysis. It is characterized by reduction—the cuticle is transparent, the feeding structures are nonfunctional, and the legs are vestigial. Moreover, the stadium is ephemeral, lasting no ≤24 h. The 2nd nonfeeding stage is a fully legged and ambulatory instar, with rudimentary feeding structures and a functional spinneret. Upon issuing from the mine, this instar spins a cocoon that is elaborately decorated with clusters of 31–114 pearly bubbles that are extruded from its anus and then individually attached to the exterior of the cocoon. We contrast the unique development of Marmara with other gracillariids and interpret the transition instar as an ontogenetic bridge, a stage of risk and metabolic cost without function.

The life history and case-building behavior of Molanna tryphena Betten from 2 spring-fed tributaries in east Texas were studied from January 1997 to May 1998. The 344 larvae, pupae, and adults sampled indicated a univoltine life cycle, with an extended adult emergence period. Fecundity was 76.2 ± 9.7 eggs per female. Larvae were recruited in spring and summer, and grew to late instars or pupae by fall. Larvae and pupae were found mainly in the sand substrate. Eggs, larvae of 2nd and 5th instars, pupae, cases, and adults are described. Case reconstruction behavior was observed and videotaped. Larvae constructed emergency cases by gluing together sand and burrowing inside to form a tube. Sand and gravel were added over the next 12 h to strengthen the tube and add the cowl and flange typical of Molannidae.

Reproductive and population parameters of melon flies, Bactrocera cucurbitae Coquillett, oriental fruit flies, B. dorsalis Hendel, and Mediterranean fruit flies, Ceratitis capitata (Wiedemann), were measured in environmental chambers maintained at temperatures of (maximum:minimum) 24:13, 24:24, 29:18, and 35:24 ± 1°C. Alternating temperature regimes more realistically approached the variation found in nature and produced higher parameters than an optimal constant temperature (24°C). Intra- and interspecific comparisons were done with 4 separate generations of wild fruit flies reared on a common natural host. All species attained their highest intrinsic rates of population increase at 29:18 or 35:24°C; C. capitata exhibited the highest intrinsic rates of increase at all temperature regimes. All species attained maximum net reproductive rates at 29:18°C, in the order C. capitata > B. dorsalis > B. cucurbitae. The 35:24°C regime caused reductions in net reproductive rates of all species, with B. dorsalis affected most strongly. Male longevity was greater than that of females for all species in all temperature regimes. Two distinctly different life history patterns were evident: (1) early reproduction, short life span, and a high intrinsic rate of increase (C. capitata), and (2) later onset of reproduction, longer life span, and a lower intrinsic rate of increase (B. cucurbitae).

The distribution of the Iowan Brood of periodical cicadas in Illinois was determined in 1997 using a global positioning system receiver and mapping software. The area contained within the distribution derived from this survey was approximately twice the area bounded by a range map published in 1975. Periodical cicadas were found in many areas not included in the earlier range map, and were absent from several areas that had been included. Periodical cicadas were patchily distributed within the boundary, being most abundant in stream woodlands and protected areas and least abundant in agricultural and urban areas. Periodical cicadas were primarily found in a soil type associated with stream woodlands, and appeared to follow forests along waterways, but it is possible that these areas serve as refugia from human activity rather than preferred habitats.

In Papua New Guinea, Coleoptera associated with coconuts share or have similar larval breeding sites, which has led to some confusion with their identity. Conclusive identification of these larvae is important before deciding whether it is possible to use biological control measures against them. The available keys are complex and do not take into account simple observable characters that can be used in the field with live specimens. Specimens of the following species were examined: Xylotrupes gideon (L.), Trichogomphus vicinus Dechambre, Oryctoderus latitarsis Boisduval, Oryctes centaurus Sternberg, Oryctes rhinoceros (L.), Scapanes australis Boisduval (Coleoptera, Scarabaeidae, Dynastinae), Dermolepida sp. (Coleoptera, Scarabaeidae, Melolonthinae), Cetoniinae (Coleoptera, Scarabaeidae) and Lucanidae (Coleoptera Scarabaeoidea). A simple key to distinguish 2 important pest species, O. rhinoceros and S. australis, from allied Coleoptera directly in the field is presented, together with drawings and photographs to illustrate distinctive features to assist in using the key. The identifications presented in the paper were checked against existing taxonomic keys.

Laboratory studies were conducted to assess the effect of temperature on the development, survival, fecundity, and longevity of Adoxophyes orana (Fischer von Röslerstamm) at 5 different constant temperatures (14, 17, 21, 25, and 30°C). Total developmental time ranged from 50.2 d at 14°C to 20.7 d at 25°C. The lower developmental threshold for each instar and total larval stage ranged from 4.9 to 7.1°C. On average 333.3 DD are required for total larval development. Survival for total larval stage was reduced substantially at the lower and higher temperatures examined. The mean longevity for females was 13.5 d at 14°C and 7.6 d at 30°C, whereas for males, mean longevity ranged from 14.9 d at 21°C to 7.9 d at 30°C. Females laid the fewest eggs (70.6) at 14°C. Intrinsic rate of increase ranges from 0.0285 at 30°C to 0.1314 at 25°C. Extreme temperatures had a negative effect on life table parameters. The effect of temperature on life history patterns of A. orana is discussed with respect to control methods and phenology models.

The influence of female body size and adult feeding on the fecundity and longevity of female Cephalonomia stephanoderis Betrem (Hymenoptera: Bethylidae), attacking the coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Scolytidae), was examined under laboratory conditions. Size and fecundity were positively correlated, whereas size had no influence on longevity of females continually provided with hosts. In contrast to theoretical models of host feeding, host feeding rate in C. stephanoderis increased over the parasitoid’s lifespan, whereas oviposition rate decreased with age. The oviposition rate was higher and the oviposition period longer in large females than in small ones. As C. stephanoderis grew older, egg and sperm exhaustion were observed, especially in small females where a single mating was not sufficient for fertilization of all the eggs deposited during their lifetime. Developmental mortality of the offspring of small females was higher compared with large females, which may be attributed to a greater ability of large females to subdue and parasitize coffee berry borer pupae. Host feeding, by itself, promoted female survival. All host stages enhanced wasp longevity, but eggs and pupae were the most effective host stages in increasing longevity. Our findings have significant implications in mass rearing and management programs by determining conditions likely to improve parasitoid production and defining desirable biological attributes of C. stephanoderis as a biological control agent of the coffee berry borer.

Microhabitats of postdiapause larvae of Euphydryas editha quino (Behr) were found to differ from random habitat points in percentage cover, grass, shade, shrub, and host plant (Plantago erecta E. Morris). Abundant host plant and little shade or overstory cover characterized larval microhabitat. Larvae found in shrub versus more open habitats occupied similar microhabitats but were significantly smaller, presumably because of delayed diapause break. Larval use of coastal sage scrub, when shrubs have been removed by disturbance (grading of dirt roads), suggests that some degree of intermediate disturbance resulting in removal of shrub canopy and increased insolation may benefit populations of this endangered insect.

The altitudinal variation in the richness and composition of communities of coprophagous beetles in a mountainous landscape in Mexico is analyzed and the results obtained are compared with those of similar studies carried out in other parts of the world. Two nonexclusive processes are proposed as responsible for the assemblage of mountain fauna: horizontal colonization by elements originating from lineages distributed at higher latitudes and vertical colonization by lineages distributed at the same latitude but at different altitudes. The current analysis supports the hypothesis that when the horizontal colonization dominates, mountain faunas show a clear altitudinal substitution between large taxa with different evolutionary histories (e.g., Scarabaeinae and Aphodiinae) and the gradient of reduction in species richness is attenuated. This occurs in mountains of different continents and depends primarily on the degree of isolation and general orientation of the mountain ranges. Conversely, when vertical colonization dominates, mountain faunas show only slight altitudinal substitution, and the reduction in richness is greater.

Differences in the geographic patterns of genitalic and nongenitalic morphological characters in Podisma sapporensis (Podisminae) were examined using the hierarchical testing procedure in common principal component analysis. This analysis was used to evaluate the extent to which the covariance structure among characters varies geographically in both sexes. Males exhibited consistency in the covariance structure among populations both in genitalic and nongenitalic characters, whereas the covariance structures of female genitalic and nongenitalic characters were not stable geographically. We suggest that the conspicuous sexual difference in covariance structure results from different selective pressures acting on genitalia: stabilizing selection is responsible for the stability of male genitalia, whereas variability in female is the result of directional sexual selection varying among populations.

Direct current electrical penetration graphs (DC-EPGs) were used to analyze the stylet penetration activities of cowpea aphid, Aphis craccivora Koch, on plants of aphid-resistant (ICV-12) and aphid-susceptible (ICV-1) cultivars of cowpea, Vigna unguiculata (L.) Walpers. Aphid stylet penetration on whole plants at seedling, flowering, and podding stages were studied in one experiment, and in another experiment excised leaves from seedling plants, excised flowers, and excised pods were tested. Electrical signals depicting the aphid stylet penetration activities on their host plants were amplified, recorded onto a paper chart recorder, and scored for specific waveform patterns. Compared with similar tissues of ICV-1, intact leaves and excised seedling foliage of ICV-12 plants caused severe disruption of aphid stylet penetration activities. This was manifested in frequent penetration attempts that were abruptly terminated or unsustained, and in shorter penetration times, signifying antixenosis resistance in ICV-12. There was reduced occurrence of E waveforms, which represent stylet activity in plant vascular tissues. Also, prior exposure of test aphids to plants of one cultivar did not significantly influence the expected stylet penetration activities on plants of the other cultivar. Overall, ICV-12 exhibited high levels of resistance against A. craccivora.

The foraging force and pollen collection of European and European × Africanized hybrid worker honey bees, Apis mellifera L., housed in a common nest environment were compared. Significant heterogeneity was found within both genotype populations for the proportion of the bees that foraged, as well as for the proportion of foragers that collected pollen. However, there was not a consistent bias for either genotype to collect pollen or to field a greater proportion of the total foraging population. These results suggest that when sharing a common environment, European × Africanized hybrids and European honey bees do not differ with respect to individual foraging decisions. Results also suggest that the pollinating efficiency of commercial colonies maintained in Africanized areas will probably not diminish as a consequence of introgression of African honey bee genes, if problems associated with their management can be controlled.

Trophallaxis, defined as the direct transfer of alimentary liquids, including suspended particulates and derivatives, from one nestmate to another via regurgitation or anal feeding, is important in the nutritional dynamics and communication of many social insects. Trophallaxis is a mechanism for the transfer of nutrients, symbionts, pheromones, and information within social insect colonies. We used the radioactive tracer cobalt-60, combined with the vital dye Nile Blue A, in a standard diet to investigate the rate, amount, and distribution pattern of alimentary liquids in the termites Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae), R. virginicus (Banks), and Zootermopsis nevadensis subsp. nevadensis (Haverty & Thorne) (Termopsidae). The technique did not affect termite survivorship and enabled determination of the rate and quantity of material transferred from identifiable, marked “donor” individuals to “recipients.” This method of tracing trophallactic transfer of alimentary fluid would be an appropriate standardized technique facilitating comparison of data among researchers. Transfer of a detectable amount of alimentary fluid in R. flavipes, R. virginicus, and Z. n. subsp. nevadensis occurred within 6–12 h after introduction of potential donors to potential recipient termites. The amount of isotope transferred from the donor to the recipient group varied, but generally ranged from 5 to 30% of the isotope initially acquired by the donor. Transfer of isotope initially was to a few members of the recipient group; isotope acquired by those recipients was distributed subsequently among the other termites. Differences in patterns of trophallaxis between Isoptera and Hymenoptera are discussed.