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Microsatellite and mitochondrial DNA (mtDNA) variability data were used to study outbreaks of Mediterranean fruit fly in California in the years 1992-94 and 1997-99. A total of 359 flies caught in monitoring traps during these years were examined at three polymorphic mtDNA restriction sites and two microsatellite loci. Composite genotypes obtained through analysis of these markers indicate at least five independent introductions of medflies into California between 1992 and 1998. Whereas the majority of specimens displayed a single mtDNA haplotype (AAA), variation of microsatellite alleles among these flies suggests at least one additional introduction in 1993 into southern California. Flies displaying the AAB haplotype sampled in 1992 both in northern and southern California shared microsatellite alleles absent in AAA flies although lacking others commonly found in AAA specimens, thus supporting the hypothesis of an independent introduction of these flies from a different source. In contrast to earlier infestations, a few specimens caught in southern California in 1993 and again in 1998 showed both mtDNA and microsatellite patterns consistent with a Hawaiian origin. Single flies collected in Santa Clara County in 1997 and in El Monte, Los Angeles County & in 1999 most likely represent a sixth and seventh distinct introduction, respectively.

We present evidence of the paraphyly of the ant genusPachycondylaresulting from our cytogenetic studies on 29 populations in 18 species from Brazil and French Guyana. It is likely that karyotypes with a large number of chromosomes and comprising mostly small acrocentric chromosomes in species within thePachycondyla stricto sensugroup resulted from a succession of centric fission events. On the other hand, karyotypes with a small chromosome number comprising mostly metacentric chromosomes are also interpreted as little derived and tend to undergo centric fission. The karyotypes of the groupNeoponeraare more heterogeneous and probably undergo successive cycles of rearrangements tending to increase the chromosome number by centric fission. Theapicalisandverenaecomplexes form two probable sister groups that evolved independently due to centric fissions (verenae) and pericentric inversions (apicalis). Our results reveal the karyotype diversity in the genus and reinforce the hypothesis on the paraphyly ofPachycondyla.

An integrative multidisciplinary approach was used to delimit boundaries among cryptic species within the Anastrepha fraterculus complex in Brazil. Sexual compatibility, courtship and sexual acoustic behaviour, female morphometric variability, variation for the mitochondrial gene COI, and the presence of Wolbachia were compared among A. fraterculus populations from the Southern (Vacaria, Pelotas, Bento Gonçalves, São Joaquim) and Southeastern (Piracicaba) regions of Brazil. Our results suggest full mating compatibility among A. fraterculus populations from the Southern region and partial pre‐zygotic reproductive isolation of these populations when compared with the population from the Southeastern region. A. fraterculus populations from both regions differed in the frequency of courtship displays and aspects of the calling phase and mounting acoustic signal. Morphometric analysis showed differences between Southern region and Southeastern region samples. All populations analyzed were infected with Wolbachia. The trees generated from the COI sequencing data are broadly congruent with the behavioural and morphometric data with the exception of one Southern population. The likely mechanisms by which A. fraterculus populations might have diverged are discussed in detail based on behavioural, morphometric, molecular genetics, and biogeographical studies.

We documented fruit fly-host associations and infestation rates over 5 yr in the state of Bahia, Brazil, by systematically collecting native and introduced fruits in backyard and commercial orchards, experimental stations, and patches of native vegetation. Fruit were collected in multiple sites in the southern and southernmost regions of Bahia. A total of 942.22 kg from 27 fruit species in 15 plant families was collected throughout this study. Of these, 15 plant species from six families were infested by Anastrepha species. A total of 11,614 fruit flies was reared from the fruit (5,178 females and 6,436 males). No specimens of Ceratitis capitata (Wiedemann) were recovered. Eleven Anastrepha species were recovered from the collected fruit: Anastrepha antunesi Lima (0.04%), Anastrepha distincta Greene (0.1%), Anastrepha fraterculus (Wiedemann) (53.5%), Anastrepha leptozona Hendel (4.5%), Anastrepha manihoti Lima (0.1%), Anastrepha montei Lima (1.0%), Anastrepha obliqua (Macquart) (33.0%), Anastrepha pickeli Lima (2.0%), Anastrepha serpentina (Wiedemann) (1.0%), Anastrepha sororcula Zucchi (3.0%), and Anastrepha zenildae Zucchi (1.8%). We recovered 1,265 parasitoids (Hymenoptera: Braconidae) from Anastrepha pupae. Three species of braconids were found to parasitize larvae of nine Anastrepha species. The most common parasitoid species recovered was Doryctobracon areolatus (Szépligeti) (81.7%), followed by Utetes anastrephae (Viereck) (12.2%) and Asobara anastrephae (Muesebeck) (6.1%). We report A. fraterculus infesting Malay apple Syzygium malaccense (L.) Merr. & L. M. Perry and A. fraterculus, A. sororcula, and A. zenildae infesting araza Eugenia stipitata McVaugh for the first time in Brazil.

Molecular identification of fruit flies in the genus Anastrepha (Diptera; Tephritidae) is important to support plant pest exclusion, suppression, and outbreak eradication. Morphological methods of identification of this economically important genus are often not sufficient to identify species when detected as immature life stages. DNA barcoding a segment of the mitochondrial cytochrome oxidase I gene has been proposed as a method to identify pests in the genus. The identification process for these fruit flies, however, has not been explained in prior DNA barcode studies. DNA barcode methods assume that available DNA sequence records are biologically meaningful. These records, however, can be limited to the most common species or lack population-level measurements of diversity for pests. In such cases, the available data used as a reference are insufficient for completing an accurate identification. Using 539 DNA sequence records from 74 species of Anastrepha, we demonstrate that our barcoding data can distinguish four plant pests: Anastrepha grandis (Macquart) (Diptera; Tephritidae), Anastrepha ludens (Loew), Anastrepha serpentina (Wiedemann), and Anastrepha striata Schiner. This is based on genetic distances of barcode records for the pests and expert evaluation of species and population representation in the data set. DNA barcoding of the cytochrome oxidase I gene alone cannot reliably diagnose the pests Anastrepha fraterculus (Wiedemann), Anastrepha obliqua (Macquart), and Anastrepha suspensa (Loew).

The Neotropical Polistinae wasps are diverse in taxonomy, social behavior, and nesting founding characteristics. Although some species in this group have been used as models for studies on wasp's biology, they are poorly known in terms of cytogenetics. Here we reported an intraspecific numerical-structural chromosome variation in the swarm-founding wasp Metapolybia decorata from the Brazilian Atlantic Rainforest using conventional and molecular cytogenetic techniques. The observed structural chromosome change involved a telomeric fusion that resulted in a chromosome number range of 2n = 34-36. The origin and geographic distribution of the variant chromosome forms as well as their frequency and maintenance in the studied populations are discussed. In addition, we reported a novel and geographically restricted deletion in the fused chromosomes indicating that the species is undergoing a continued process of karyotype evolution leading to fused chromosome stabilization by elimination of inactive centromeric sequences. Evidence of differences in the telomeric sequences of this wasp was also found by in situ hybridization using the motif (T2AG2)7 as probe.