Females of four common Culex (Culex) species from Florida were analyzed for isoenzymes using polyacryamide gel electrophoresis. Ten enzymes that yielded 11 putative loci were studied. Most of the loci showed diagnostic characteristics in the four species, but four of the loci (glycerol-3-phosphate dehydrogenase [Gpd-2], hexokinase [Hk], isocitrate dehydrogenase [Idh-1], and malate dehydrogenase [Mdh]) could be used in sequence to identify the four Culex species. Culex salinarius and Cx. p. quinquefasciatus could be separated from Cx. restuans andCx. nigripalpus by Mdh locus. Culex salinarius could be distinguished from Cx. p. quinquefasciatus by Hk locus and Cx. nigripalpus could be distinguished from Cx. restuans, by Idh-1 and/or Gpd-2 loci. Randomly combined specimens of these four Culex species were identified accurately by using these enzyme loci.

Laboratory trials were used to estimate the toxicity of sucrose octanoate to beneficial insects representing four insect orders of importance in biological control in Florida citrus. First instars of the ladybeetles Cycloneda sanguinea L., Curinus coeruleus Mulsant, Harmonia axyridis Pallas and Olla v-nigrum Mulsant (Coleoptera: Coccinellidae) and the lacewing Chrysoperla rufilabris Burmeister (Neuroptera: Chrysopidae) survived topical sprays of sucrose octanoate at 8,000 ppm without significant mortality, a concentration corresponding to twice the recommended field rate required to kill aphids and other soft bodied pests. Similarly, adults of the red scale parasitoid, Aphytis melinus De Bach (Hymenoptera: Aphelinidae) and second instars of the predatory bug Orius insidiosus (Say) (Hemiptera: Anthocoridae) survived 24 h exposures to residues of 8,000 ppm sucrose octanoate on leaf disks without significant mortality. The efficacy of sucrose octanoate as a contact insecticide against various homopteran pests of citrus, combined with its low toxicity to key beneficial insects in the citrus ecosystem, suggest that it may be a valuable material for incorporation into IPM programs for Florida citrus.

The objectives of this study were to determine the population fluctuations of the citrus leafminer, Phyllocnistis citrella, and its parasitoids in three locations of Ecuador, to identify and determine the geographic distribution of P. citrella parasitoids within Ecuador, and to establish which of eleven citrus species supported higher numbers of P. citrella and its parasitoids. The highest population density of P. citrella occurred during the dry season. The highest infestations in three localities were in Lodana (43.8%) in October, in Riochico (45.7%) in November, and in La Unión (17.3%) in December. The greatest percentages of parasitism occurred in Lodana in March (60%), in Riochico in January (18.9%), and La Unión in December (50%). The species Ageniaspis citricola Logvinovskaya, Galeopsomyia sp., and Elasmus tischeriae Howard were identified with 28.4, 2.2, and 0.07% parasitism, respectively. Although this is the first report of A. citricola in Ecuador, it is widely distributed in the main citrus producing zones of the country. Orange and grapefruit yielded higher numbers of citrus leafminers and their natural enemies than other citrus species.

Species-specific molecular markers were developed to identify and distinguish between two parasitoids of the brown citrus aphid, Toxoptera citricida Kirkaldy, in Florida. PCR primers were developed for Lysiphlebus testaceipes Cresson and Lipolexis oregmae Gahan (= scutellaris Mackauer) with DNA sequences from the internal transcribed spacer (ITS) region between the 5.8S and 28S nuclear rRNA genes. With High-fidelity PCR, the L. testaceipes-specific primer produced a 520-bp band while that of L. oregmae resulted in a 270-bp band. Eggs of both parasitoids within their aphid hosts could be detected by 6 h after oviposition, but 100% detection rates only occurred after 24 h. A sensitivity analysis indicated that a parasitoid egg within a single aphid could be detected 100% of the time when combined with DNA from up to 36 unparasitized aphids. A single first instar parasitoid could be detected by High-fidelity PCR when the parasitized aphid was combined with up to 500 unparasitized aphids, indicating a high level of sensitivity. Species-specific primers detected both immature parasitoid species within aphids commonly found in citrus in Florida, including Aphis craccivora Koch, Aphis gossypii Glover, Aphis spiraecola Patch, Toxoptera aurantii Boyer and T. citricida. This High-fidelity PCR assay provides an efficient method to monitor establishment of L. oregmae in citrus groves in this classical biological control program in Florida.

Larvae of the Diaprepes root weevil, Diaprepes abbreviatus (L.), were reared from hatching on an artificial diet containing four concentrations of two copper compounds, cupric sulfate (CuSO₄) or cupric hydroxide [Cu(OH)₂]. Negative effects of copper on insect development were observed only for early instars. Survival of larvae from hatching to 4 weeks of age was significantly affected by the copper compounds compared with the artificial diet alone, and greater mortality was associated with CuSO₄ compared with Cu(OH)₂. The two compounds had equivalent effects on larval weight gain of early instars. Weight gain was negatively correlated with increasing copper concentration. No effect of copper was observed on late instars maintained on these diets beyond the initial 4 weeks. Larval and pupal period, weight gain, and survival of late instars were statistically similar. No effect on larval survival or weight gain was observed when copper solutions were applied at nonphytotoxic levels to two varieties of citrus rootstock. The potential for manipulating citrus tree copper content to control this pest is discussed.

Hylesia metabus is a species of moth, distributed principally in northeastern Venezuela. Female moths use their abdominal setae to cover their egg masses. Contact with these setae can cause a severe dermatitis in humans. Setae from males do not produce these symptoms. The external morphology of the abdominal setae in male and female moths was described and the effect of the setae on ant behavior was studied. We classified the setae into four types, S1, S2, S3 and S4. In females, two of these types were found in the dorsal region; S1 and S2 show a porous structure and measure 2000 μm and 155 μm in length, respectively. In the ventral part of the abdomen we observed three setae types, S1, S3 which are 190 μm long and have small barbs along their length directed towards the apex, and S4 which have numerous barbs at the base, but further up flatten out, with barbs along both sides, before tapering off at the apex. S4 also were found in the lateral zones of the abdomen and were the predominant type of setae covering the egg masses. Only S1 setae were found in males. Egg masses not covered by setae were examined and transported by Pheidole ants, whereas covered eggs were largely avoided. The morphology of the S3 and S4 setae types suggests that these may be related to the urticating properties reported for the moth. Ant avoidance of setae covered eggs suggests that these protect the eggs from at least some predators.

Zeta argillaceum (L.), a common neotropical wasp, is established in Florida. The characteristic mud potter-like nests are easily recognized. They prey on geometrid caterpillars. Their nests are reused by various arthropods, forming an ecological web similar to that of other mud dauber wasps. Prey, inquilines, parasites, and scavengers found inside the nests are presented.

We evaluated the attractiveness of three aqueous dilutions of human urine (HU 50, 25, and 12.5%) to adults of pestiferous and nonpestiferous Anastrepha species (Diptera: Tephritidae) in small guava, grapefruit, mango, and sapodilla orchards with glass McPhail traps. As control treatments we used a commercially available hydrolyzed protein bait (Captor Plus®) and tap water. In the guava orchard, the three urine dilutions were as effective as hydrolyzed protein in attracting A. fraterculus. Also, when 25 and 50% urine were used, 93 and 96%, respectively, of the adults captured were females. In the grapefruit orchard, protein-baited traps captured significantly more A. ludens than urine-baited traps. In the mango orchard, both A. obliqua and A. serpentina were more attracted to hydrolyzed protein than to any other bait treatment. In the sapodilla orchard, traps baited with 50% urine surpassed all other treatments in the capture of A. serpentina and A. obliqua. Our findings indicate that human urine performs as well or better than hydrolyzed protein in certain types of orchards. They also support the notion that there is no “universal” Anastrepha bait. We conclude that human urine is a viable, low-tech alternative Anastrepha bait for subsistence or low income, small-scale fruit growers in rural Latin America.

A new species of myrmicine ant is described from Florida: Leptothorax palustris is known from workers and associated queens and males collected in a marsh and in frequently flooded pinelands in the Apalachicola National Forest in northwestern Florida. Nests are near the surface in root mats that extend into small open sandy hummocks. The species resembles Leptothorax texanus Wheeler, a species of adjacent well-drained sandy sites, differing primarily in the structure of the petiole and postpetiole and color. Leptothorax davisi Wheeler is synonymized with Leptothorax texanus Wheeler (new synonymy); this is based on extensive and previously unknown variability in L. texanus, even in single sites and within nest series. An illustrated key is presented for the identification of the eleven species of Leptothoraxknown from the Atlantic Coastal states north through North Carolina, with the addition of Alabama.

The impacts of two post-treatment irrigation timings on the field efficacy and residual activity of deltamethrin against nymphs of the southern mole cricket, Scaptericus vicinus Giglio-Tos, and the tawny mole cricket, S. borellii Scudder, as well as movement of deltamethrin in the turfgrass profile, were investigated in 1998. Deltamethrin followed by irrigation 24 h after treatment provided the best mole cricket control versus immediate irrigation in both field and greenhouse studies. Regardless of irrigation timing, grass clippings had the highest residual levels of deltamethrin followed by the thatch layer. Clipping residues were higher with post 24 h irrigation than immediate irrigation with few residues in the upper soil profile (top 5 cm).

Cargo aircraft arriving at Miami International Airport from foreign origins were randomly selected and inspected from September 1998 to August 1999 for the presence of live hitchhiking insects. An overall infestation (= approach) rate of 10.4% was found, with the rate for aircraft arriving from Central American countries noticeably greater at about 23%. Quarantine-significant taxa from 33 families in five orders were detected, with members of Lepidoptera and Coleoptera most frequently encountered. More than 40% of infested aircraft contained multiple insect taxa. No correlation was established between the presence of hitchhiking insects and the time of day (night vs. day) during which cargo was loaded at points of origin or the nature of cargo on board. Quarantine-significant organisms arrived in cargo aircraft during all months of the year. Significant seasonality (dry season vs. wet) was observed for pests on flights arriving from Central America, with separate peaks noted in May and October.