Hosts and parasitoids of fruit flies (Diptera: Tephritoidea) in the State of Tocantins, Brazil

Fruit flies were obtained from 13 species of naturally infested fruits in the central region of Tocantins State, from January to October 2005. A total of 1,753 female flies were collected that belong to 11 species: Anastrepha coronilli Carrejo & González, A. fraterculus (Wied.), A. mucronota Stone, A. obliqua (Macquart), A. sororcula Zucchi, A. striata Schiner, A. turpiniae Stone, A. zenildae Zucchi, Anastrepha sp., Ceratitis capitata (Wied.) and Neosilba sp. Also six species of parasitoids were associated to Anastrepha larvae: Asobara anastrephae (Muesebeck), Doryctobracon areolatus (Szépligeti), Doryctobracon sp., Opius bellus Gahan, Opius sp. and Utetes anastrephae (Viereck).     

Fruit flies (Diptera: Tephritidae) and their parasitoids (Hymenoptera: Braconidae) associated to host plants in the southern region of Bahia State

The association among Anastrepha species, braconid parasitoids and host fruits in southern Bahia is recorded. Doryctobracon areolatus (Szépligeti) was associated with A. serpentina (Wied.) in Pouteria caimito, A. bahiensis Lima in Helicostylis tomentosa, A. sororcula Zucchi in Eugenia uniflora, and A. obliqua (Macquart) in Spondias purpurea. Anatrepha obliqua was unique in fruits of Averrhoa carambola, but associated with D. areolatus, Asobara anastrephae (Muesebeck) and Utetes anastrephae (Viereck). In Achras sapota, A. serpentina was associated with A. anastrephae and D. areolatus, while in Psidium guajava, A. fraterculus (Wied.) and A. sororcula were associated with D. areolatus and U. anastrephae.     

Measurement of the aculeus for the characterization of five Anastrepha species of the fraterculus group (Diptera: Tephritidae)

Species identification of the genus Anastrepha Schiner is based mostly on the shape of the aculeus apex. In some species groups, such as fraterculus, species are separated by subtle differences in the aculeus apex, namely Anastrepha fraterculus (Wied.), A. obliqua (Macquart), A. sororcula Zucchi, A. zenildae Zucchi and A. turpiniae Stone. In order to help the identification, the aculei of these five species from 25 localities of 17 Brazilian states were measured. The aculeus and apex lengths of these species vary along geographical distribution and even from specimens reared from same host. For this reason and due to superimposition, these Anastrepha species cannot be separated based on the two measures exclusively.     

Susceptibility of guava genotypes to natural infestation by Anastrepha spp. (Diptera: Tephritidae) in the municipality of Monte Alegre do Sul, state of São Paulo, Brazil

The infesting species and their infestation indices of fruit flies were determined for eleven guava genotypes (Psidium guajava L.). From March to April 2000, ten mature fruits of each genotype were harvested at weekly intervals from insecticide unsprayed trees located in the municipality of Monte Alegre do Sul, SP, Brazil. Fruits were brought to the laboratory, weighed and placed in individual plastic cups containing sand at the bottom to obtain the tephritid pupae. About 95% of guavas produced fruit fly puparia. Of the 682 Anastrepha females recovered, four species were identified: A. fraterculus (Wied.) (86.5%), A. obliqua (Macquart) (10.8%), A. bistrigata Bezzi (1.8%) and A. sororcula Zucchi (0.9%). Three species of parasitoids Braconidae (Opiinae) were recovered: Doryctobracon areolatus (Szépligeti), Doryctobracon brasiliensis (Szépligeti) and Utetes anastrephae (Viereck). The genotypes differ in level of infestation depend on the collecting time. The genotypes 'L2P4 Vermelha', 'Ruby Suppreme' and 'Webber Suppreme' showed the lowest susceptibility to tephritids in terms of puparia per fruit. The variability of infestation among the guava genotypes and the reasons for increasing fruit fly infestations along the time were discussed.     

Hymenopteran parasitoids associated with frugivorous larvae in a Brazilian caatinga-cerrado ecotone

The purpose of this study was to investigate native species of parasitoids of frugivorous larvae and their associations with host plants in commercial guava orchards and in typical native dry forests of a caatinga-cerrado ecotone in the State of Minas Gerais, Brazil. Nine species of parasitoids were associated with larvae of Anastrepha (Tephritidae) and Neosilba (Lonchaeidae) in fruit of Psidium guajava L. (Myrtaceae), Ziziphus joazeiro Mart. (Rhamnaceae), Spondias tuberosa Arruda (Anacardiaceae), Spondias dulcis Forst. (Anacardiaceae), Syzygium cumini (L.) Skeels (Myrtaceae), and Randia armata (Sw.) DC. (Rubiaceae). Doryctobracon areolatus was the most abundant species, obtained from puparia of Anastrepha zenildae, An. sororcula, An. fraterculus, An. obliqua, and An. turpiniae. This is the first report of Asobara obliqua in Brazil and of As. anastrephae and Tropideucoila weldi in dry forests of Minas Gerais State. The number of species of parasitoids was higher in areas with greater diversity of cultivated species and lower pesticide use. The forest fragments adjacent to the orchards served as shelter for parasitoids of frugivorous larvae.     

Native and introduced host plants of Anastrepha fraterculus and Ceratitis capitata (Diptera: Tephritidae) in northwestern Argentina

Wild or commercially grown, native and exotic fruit were collected in 30 localities in the Tucumán province (NW Argentina) from January 1990 to December 1995 to determine their status as hosts of Anastrepha fraterculus (Wiedemann) and/or Ceratitis capitata (Wiedemann), the only two fruit fly species of economic and quarantine importance in Argentina. A total of 84,094 fruit (3,466.1 kg) representing 33 species (7 native and 26 exotic) in 15 plant families were sampled. We determined the following 17 host plant associations: Annona cherimola Miller (Annonaceae), Citrus paradisi Macfadyn (Rutaceae), Diospyros kaki L. (Ebenaceae), Eugenia uniflora L., Psidium guajava L., Myrcianthes pungens (Berg) Legrand (Myrtaceae), Ficus carica L. (Moraceae), Juglans australis Grisebach (Juglandaceae), Mangifera indica L. (Anacardiaceae), Eriobotrya japonica (Thunb.) Lindl., Prunus armeniaca L., P. domestica L., and P. persica (L.) Batsch (Rosaceae) were infested by both A. fraterculus and C. capitata. Citrus aurantium L., Citrus reticulata Blanco, Citrus sinensis (L.) Osbeck (Rutaceae), and Passiflora caerulea L. (Passifloraceae) were only infested by Ceratitis capitata. Out of a total of 99,627 adults that emerged from pupae, 69,180 (approximately 69.5%) were Anastrepha fraterculus, 30,138 (approximately 30.2%) were C. capitata, and 309 (approximately 0.3%) were an unidentified Anastrepha species. Anastrepha fraterculus predominated in native plant species while C. capitata did so in introduced species. Infestation rates (number of larvae/kg of fruit) varied sharply from year to year and between host plant species (overall there was a significant negative correlation between fruit size and infestation level). We provide information on fruiting phenology of all the reported hosts and discuss our findings in light of their practical (e.g., management of A. fraterculus and C. capitata in citrus groves) implications.     

Susceptibility of six Arabic coffee cultivars to fruit flies (Diptera: Tephritoidea) under shaded and unshaded organic management in Valença, State of Rio de Janeiro, Brazil

The infestation indices by fruit flies were determined for six cultivars of Coffea arabica L. in shaded and unshaded systems under organic management. The experiment was set in a completely randomized design with a split-split-plot arrangement and four replicates. A 250g-sample of maturing fruits per plot was harvested in May 2005. The cultivars Icatu Amarelo and Catucaí Amarelo were the least susceptible to attack by tephritids in both systems. As for lonchaeids, Oeiras, Catucaí Amarelo and Catuaí Vermelho were the least susceptible cultivars in the shaded system, and there was no difference among the cultivars in the unshaded system. The following tephritid species were obtained: Ceratitis capitata (Wiedemann), Anastrepha fraterculus (Wiedemann) and A. sororcula Zucchi (Tephritidae). Lonchaeids were represented by Neosilba bifida Strikis & Prado, N. certa (Walker), N. glaberrima (Wiedemann), N. pendula (Bezzi), N. pseudopendula (Korytkowski and Ojeda), Dasiops rugifrons Hennig, Neosilba n.sp.10 and Neosilba n.sp.14.     

Faunistic analysis of fruit flies (Diptera: Tephritidae) in the Northern and Northwestern Regions of Rio de Janeiro State, Brazil

This study aimed to characterize the fruit fly populations in three municipalities of the Northern region and two municipalities of the Northwestern region of Rio de Janeiro State, Brazil, and to evaluate the similarity among their populations. A faunistic analysis was performed from the fruit fly specimens captured in plastic McPhail traps with an aqueous solution of hydrolyzed protein to 5% placed in orchards of guava (Psidium guajava L.) and/or other fruits during 26 months. The total of 3,952 females of 15 species of Anastrepha Schiner and 277 females of Ceratitis capitata (Wied.) was captured. The species richness differed among the municipalities, with the highest value in S?o Francisco do Itabapoana (S = 14), resulting on the highest Shannon-Wiener index (H = 1.27). The equitability was low in the five municipalities due to the dominance of one unique fruit fly species. The predominant species (more frequent, constant and dominant) were Anastrepha obliqua (Macquart) in Campos dos Goytacazes and S?o Francisco do Itabapoana, Anastrepha fraterculus (Wied.) in Cambuci and Itaocara, and Anastrepha sororcula Zucchi in S?o Jo?o da Barra. Fruit fly populations had low diversity index of Margalef (alpha = 0.58 to 1.82). Regarding to fruit fly species composition, the populations in S?o Jo?o da Barra and Cambuci were more similar between each other, composing a distinct group from the populations in Campos dos Goytacazes and Itaocara. These two groups differed quite a lot from the population in S?o Francisco do Itabapoana.     

Fruit flies (Diptera, Tephritidae) and their associations with native host plants in a remnant area of the highly endangered Atlantic Rain Forest in the State of Espírito Santo, Brazil

The results presented in this paper refer to a host survey, lasting approximately three and a half years (February 2003-July 2006), undertaken in the Vale do Rio Doce Natural Reserve, a remnant area of the highly endangered Atlantic Rain Forest located in Linhares County, State of Espírito Santo, Brazil. A total of 330 fruit samples were collected from native plants, representing 248 species and 51 plant families. Myrtaceae was the most diverse family with 54 sampled species. Twenty-eight plant species, from ten families, are hosts of ten Anastrepha species and of Ceratitis capitata (Wiedemann). Among 33 associations between host plants and fruit flies, 20 constitute new records, including the records of host plants for A. fumipennis Lima and A. nascimentoi Zucchi. The findings were discussed in the light of their implications for rain forest conservation efforts and the study of evolutionary relationships between fruit flies and their hosts.     

Diversity of flies (Diptera: Tephritidae and Lonchaeidae) in organic citrus orchards in the vale do Rio Caí, Rio Grande do Sul, southern Brazil

This study was carried out in the Counties of Montenegro and Pareci Novo located in the region of the Vale do Rio Cai, Rio Grande do Sul, Southern Brazil, aiming to determine the fruit fly species of Tephritidae and Lonchaeidae that occur in organic orchards of sweet orange [Citrus sinensis (L.) Osb.] cultivar Céu, and Murcott tangor (Citrus reticulata Blanco x C. sinensis), during the fruit ripening stages in 2003 and 2004. Eight McPhail traps baited with integral grape juice diluted to 25% were installed in four orchards, two in each citrus species. The traps were checked weekly, when the baits were changed, the flies separated and preserved in 70% ethyl alcohol. Fruits were also sampled from the orchards, placed in containers with damp soil and closed with a mesh. The tephritid flies represented 86.2% of all captured flies in the four orchards during both years. Five Tephritidae species were captured from traps: Anastrepha fraterculus (Wiedemann), Anastrepha grandis (Macquart), Anastrepha pseudoparallela (Loew), Anastrepha dissimilis Stone and Ceratitis capitata (Wiedemann). The captured species of Lonchaeidae were: Neosilba zadolicha McAlpine & Steyskal, Neosilba n.sp.3, Neosilba sp. and Lonchaea sp. Anastrepha fraterculus was found in 99% of the fruit samples, both in 'Céu' orange and 'Murcott' tangor, and Neosilba n.sp.3 were only obtained from 'Murcott' tangor fruits.     

Anastrepha ludens and Anastrepha serpentina (Diptera: Tephritidae) do not infest Psidium guajava (Myrtaceae), but Anastrepha obliqua occasionally shares this resource with Anastrepha striata in nature

This study examined whether economically important fruit fly species Anastrepha ludens (Loew), Anastrepha serpentina (Wiedemann), and Anastrepha obliqua (Macquart) (Diptera: Tephritidae) may opportunistically exploit guavas, Psidium guajava L. (Myrtaceae), growing near preferred natural hosts. We collected 3,459 kg of guavas and 895 kg of other known host species [sour orange, Citrus aurantium L.; grapefruit, Citrus paradisi Macfadyen; mango, Mangifera indica L.; white sapote, Casimiroa edulis La Llave and Lex.; sapote, Pouteria sapota (Jacq.); sapodilla, Manilkara zapota L.; and wild plum, Spondias purpurea L. and Spondias mombin L.] along an altitudinal gradient over a 4-yr period (2006-2009). Plants were growing in sympatry in 23 localities where the guavas are usually infested in the state of Veracruz, M6xico. The guava samples yielded 20,341 Anastrepha spp. pupae in total (overall mean, 5.88 pupae per kg of fruit). Confirming previous reports, Anastrepha fraterculus (Wiedemann) and Anastrepha striata (Schiner) were found heavily infesting guavas in Veracruz. Importantly, although we did not find evidence that A. ludens and A. serpentina are able to attack this valuable commodity, we document for the first time in the agriculturally important state of Veracruz that P. guajava is an alternative natural host plant of A. obliqua. We recovered two fruit in the mango-growing locality of la Vibora, Tlalixcoyan, that harbored larvae of A. striata and A. obliqua. This finding has important practical implications for management of A. obliqua. Over the entire altitudinal gradient, when individual fruit infestation was examined, a dynamic pattern of species dominance was unveiled with guavas growing below 800 m above sea level mainly attacked by A. striata and a progressive replacement with increasing altitude by A. fraterculus. Interestingly, most individual fruit examined (97%) harbored a single species of fruit fly, a finding that may be taken as evidence of competitive displacement among sympatric species of fruit flies. Based on this study and previously published work by us on this topic, we conclude that literature reports indicating that A. ludens and A. serpentina infest guavas under field conditions should be questioned.     

Nonhost status of Citrus sinensis cultivar valencia and C. paradisi cultivar ruby red to Mexican Anastrepha fraterculus (Diptera: Tephritidae)

Anastrepha fraterculus (Wiedemann) is recognized as a pest of citrus, apples, and blackberries in South America. In Mexico, it is mainly found in fruit of the family Myrtaceae and has never been reported infesting citrus. Here, we sought to determine whether females stemming from Mexican A. fraterculus populations (collected in the state of Veracruz) would lay eggs in 'Valencia' oranges and 'Ruby Red' grapefruit and, if so, whether larvae would hatch and develop. We worked under laboratory and seminatural conditions (i.e., gravid females released in fruit-bearing, bagged branches in a commercial citrus grove) and used Anastrepha ludens (Loew), a notorious pest of citrus, as a control species. Under laboratory conditions, A. ludens readily accepted both oranges and grapefruit as oviposition substrates, but A. fraterculus rarely oviposited in these fruit (but did so in guavas, a preferred host) and no larvae ever developed. Eggs were deposited in the toxic flavedo (A. fraterculus) and nontoxic albedo (A. ludens) regions. Field studies revealed that, as was the case in the laboratory, A. fraterculus rarely oviposited into oranges or grapefruit and that, when such was the case, either no larvae developed (oranges) or of the few (13) that developed and pupated (grapefruit), only two adults emerged that survived 1 and 3 d, respectively (5-17% of the time necessary to reach sexual maturity). In sharp contrast, grapefruit exposed to A. ludens yielded up to 937 pupae and adults survived for >6 mo. Therefore, the inability of Mexican A. fraterculus to successfully develop in citrus renders the status of Mexican A. fraterculus as a pest of citrus in Mexico as unsubstantiated.     

Long aculeus and behavior of Anastrepha ludens render gibberellic acid ineffective as an agent to reduce 'ruby red' grapefruit susceptibility to the attack of this pestiferous fruit fly in commercial groves

Treating Mexican grapefruit with gibberellic acid (GA3) before color break, significantly delayed peel color change and increased peel puncture resistance, but it did not reduce grapefruit susceptibility to Mexican fruit fly, Anastrepha ludens (Loew) attack under natural conditions. Despite GA3 treatments, larval infestation levels increased with higher fruit fly populations, which also increased as the season progressed. Late in the season, infestation levels were even higher in GA3-treated fruit compared with untreated fruit, possibly because treated fruit were in better condition at that stage. Egg clutch size was significantly greater in very unripe, hard, GA3-treated fruit at the beginning of the harvest season and in December, compared with control fruit. Under laboratory conditions, egg injection into different regions of the fruit suggested that A. ludens eggs are intoxicated by peel oil content in the flavedo region. However, A. ludens' long aculeus allows females to oviposit eggs deeper into the peel (i.e., albedo), avoiding toxic essential oils in the flavedo. This makes A. ludens a particularly difficult species to control compared with other citrus-infesting species such as Anastrepha suspensa (Loew), Anastrepha fraterculus (Wiedemann), and Ceratitis capitata (Wiedemann) (fly species with significantly shorter aculei), which can be effectively managed with GA3 sprays. We discuss our findings in light of their practical implications and with respect to the oviposition behavior of various fruit flies attacking citrus.     

Host breadth and parasitoids of fruit flies (Anastrepha spp.) (Diptera: Tephritidae) in Puerto Rico

Twenty fruit species representing 12 families were collected from various regions in western Puerto Rico and monitored for the emergence of Anastrepha spp. pupae. We collected 14,154 tephritid pupae from 16 fruit species representing 10 families. The relative infestations of these fruits (pupae per kilogram of fruit) were recorded. Recorded host ranges were not in complete agreement with those reported in the literature. This host-use pattern should give pause to regulators of fruit importation and exportation that base their decisions on literature from regions other than those of immediate interest to them. We recovered the braconid parasitoid Utetes anastrephae (Viereck) from tephritid pupae collected from Mangifera indica L., Spondias mombin L., Psidium guajava L., Chrysobalanus icacos L., Terminalia catappa L., and Garcinia intermedia (Pittier) Hammel. We collected one specimen of the parasitoid Doryctobracon aerolatus (Szepligeti) from the west coast (A?asco), which had not been previously reported in Puerto Rico. We present a preliminary phenology of what are probably the primary fruit hosts of the Anastrepha spp. of Puerto Rico. We also present the first report of Garcinia intermedia (Pittier) Hammel and Coffea arabica L. as reproductive hosts of A. suspensa.     

Fruit infesting tephritids [Dipt.: Tephritidae] and associated parasitoids in Chiapas,Mexico

A total of 1,302 parasitoids representing 8 species and 4 families were recovered from 9,818 fruit fly host fruits sampled. The most common parasitoid species wasDiachasmimorpha longicaudata (Ashmead). Average percent parasitism ranged between 0.44 and 29.23%. Parasitoid emergence data indicate thatAnastrepha ludens (Loew),A. obliqua (Sein),A. serpentina (Wiedeman),A. striata (Schiner) andToxotrypana curvicauda (Gerstaecker) were subject to parasitism. We provide information on the population fluctuation ofAnastrepha ludens, A. obliqua, A. serpentina, A. distincta (Greene),A. striata, A. fraterculus (Wiedeman),A. chiclayae (Greene),A. montei (Costa Lima),A. leptozona (Hendel) andA. tripunctata (Wulp).Anastrepha ludens andA. obliqua were the most common species, representing 95.3% of all fruit fly species caught in McPhail traps.      

Movement of Anastrepha fraterculus from native breeding sites into apple orchards in Southern Brazil

We report movements exhibited by adults of Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) from patches of native forests into apple orchards in Southern Brazil. Two mark-release-recapture experiments were conducted using wild flies. Released flies behaved as wild unmarked flies, and periods of peak captures of marked adults coincided with those of unmarked ones. In the first experiment (December 94), out of 2154 released adults, 7.1% were recaptured from day 2 through day 20 after release. Captures peaked from day 7–9 after release. Most marked flies (94.7%) were trapped within 200 m of the release point but eight adults (seven females and one male) were captured in traps placed in an apple orchard, 400–800 m from the release point. The vegetation found between forest and orchard consisted of pastures and annual crops. In the second experiment (January 95), a total of 3284 flies was released in an area where native host plants were abundant and located at ca. 900 m from an apple orchard. In all, 37.1% of marked flies were captured, 99.0% of them at a distance of less than 200 m from the release point. Four adults were captured in an apple orchard, 7 to 24 days after release. They may have reached the orchard through a large and continuous area of native forest. Our results unequivocally demonstrate that A. fraterculus adults are able to disperse from native forests where they originate and invade apple orchards, probably foraging for food and oviposition sites.     

Morphometric analysis of Mexican and South American populations of the Anastrepha fraterculus complex (Diptera: Tephritidae) and recognition of a distinct Mexican morphotype

Discriminant function and cluster analyses were performed on 19 morphometric variables of the aculeus, wing and mesonotum to determine whether populations of Anastrepha fraterculus (Wiedemann) from different parts of Mexico could be distinguished from populations from South America. Samples were collected from seven localities across Mexico, two from Brazil, and one each from Colombia and Argentina. Results showed there were statistically significant differences between Mexican and South American populations with respect to the aculeus (tip length, length of serrated section, mean number of teeth) and wing (width of S-band and connection between S- and V-bands). The degree of morphological variation observed among Mexican populations was extremely low, and as a consequence, the Mexican populations were identified as a single morphotype by discriminant analysis. The 'Andean morphotype'consisting of the Colombian population, and the 'Brazilian morphotype'consisting of the two Brazilian populations plus the single Argentinian population were also distinguished. It was concluded that the macro-geographical morphotypes from Mexico, Colombia, and Brazil plus Argentina correspond to three distinct taxonomic entities. Comparisons of results with those obtained from behavioural, karyotypic, isozyme and DNA studies suggest that sufficient evidence now exists to name a new Mexican species from within the A. fraterculus complex. This will be done in a separate publication. A provisional key to the morphotypes of A. fraterculus studied is provided.     

Factors affecting Anastrepha fraterculus female receptivity modulation by accessory gland products

In the context of the sterile insect technique (SIT), mass-rearing and male irradiation are imperative. Post-teneral treatments such as the addition of protein in adult's male diet and male hormonal treatment are used to improve sexual performance and to accelerate sexual maturation. In this work we investigated the effect of male accessory glands products (AGPs) on female receptivity of the South American fruit fly Anastrepha fraterculus (Wiedemann), and the effect of strain rearing history, male irradiation, male diet and hormonal treatment on AGPs. Injections of aqueous extracts of male accessory glands into the abdomen of females reduced their receptivity. The AGPs from laboratory males were more effective in inhibiting female receptivity, compared to AGPs from wild males, irrespective of females' origin. The AGPs from fertile males were more effective than AGPs from sterile males. The AGPs from protein-fed males were more effective than AGPs from sugar-fed males. Finally, the AGPs of males treated with juvenile hormone were less effective in inhibiting female receptivity than AGPs of untreated males. We conclude that inhibition of sexual receptivity of A. fraterculus mated females is mediated by products in male accessory gland's and the way that these products act vary widely according to the effect of extrinsic factors. We discuss the results in the perspective of the SIT application for A. fraterculus.     

Nonhost status of commercial Persea americana 'Hass' to Anastrepha ludens, Anastrepha obliqua, Anastrepha serpentina, and Anastrepha striata (Diptera: Tephritidae) in Mexico

The objective of this study was to determine the host status in Mexico of commercially cultivated and marketed avocado, Persea americana (Mill.), 'Hass' to Anastrepha ludens (Loew), Anastrepha obliqua (Macquart), Anastrepha serpentina (Wiedemann), and Anastrepha striata (Schiner) (Diptera: Tephritidae). Experiments in Michoacán, Mexico, were carried out in six orchards located at three altitudes above sea level during two times (August-October 2001 and April-June 2002). They included choice ('Hass' avocado plus natural host) and no-choice foraging behavior tests on trees under field cages; no-choice, forced infestation trials on caged, fruit-bearing branches in the field, and with individual fruit under laboratory conditions; infestation trials using 'Hass' avocados left unprotected over 1 and 7 d on the ground of orchards; studies to ascertain depth of oviposition and determine egg hatchability; and experiments to determine susceptibility by using time elapsed since removal of fruit from tree as the experimental variable. We trapped adult Anastrepha (n = 7,936) in all orchards and dissected fruit (n = 7,695) from orchards and packing houses (n = 1,620) in search of eggs or larvae. Most (96.7%) A. ludens, A. obliqua, A. striata, and A. serpentina adults were captured in low-elevation orchards. No eggs or larvae were detected in any of the fruit from foraging behavior studies or dissected fruit from orchards or packing houses. Of 5,200 mature, intact fruit on trees in the field forcibly exposed to no-choice female oviposition activity (five females/fruit), we only found four fruit infested by A. ludens but no adults emerged. 'Hass' avocados only became marginally susceptible to attack by A. ludens (but not A. obliqua, A. serpentina, and A. striata) 24 h after being removed from the tree. Fruit placed on the ground in orchards (n = 3,600) were occasionally infested by Neosilba batesi (Curran) (Diptera: Lonchaeidae), a decomposer, but not Anastrepha spp. Based on our results, commercially cultivated and marketed P. americana 'Hass' should not be considered a natural host of A. ludens, A. obliqua, A. striata, and A. serpentina in Mexico.