Fly Puparia Research Articles

Nosema Disease of the Parasitoid Muscidifurax raptor (Hymenoptera: Pteromalidae): Prevalence, Patterns of Transmission, Management, and Impact

Abstract The microsporidium Nosema muscidifuracis was found in 1.1 and 10.7% of wild Muscidifurax raptor collected on New York dairy farms in 1991 and 1992. Higher (84%) levels of infection were observed on farms where infected M. raptor from a commercial insectary were released. Adult M. raptor became infected (100%) after feeding on spore suspensions of N. muscidifuracis, whereas house fly (Musca domestica L.) adults and larvae did not. Adult M. raptor became infected (16-25%) after feeding on infected parasitoid immatures within host puparia. Transmission rates of N. muscidifuracis increased with increasing parasitoid crowding levels because of cannibalism by healthy parasitoid immatures on infected immatures in superparasitized hosts. Maternal transmission was 100% efficient but there was no paternal or venereal transmission. Disease was reduced 35-93% by immersing infected parasitoid eggs within fly puparia in a 47°C water bath for 30-60 min. Eliminating disease from an established laboratory colony of M. raptor resulted in a 10-fold increase in parasitoid fecundity.

Spittle Maggots: Studies on Cladochaeta Fly Larvae Living in Association with Clastoptera Spittlebug Nymphs

-Cladochaeta (Diptera: Drosophilidae) larvae live in nymphal spittle masses of New World spittlebugs (Homoptera: Cercopoidea). Cladochaeta inversa (Walker) is widely distributed on Clastoptera obtusa (Say) nymphs in eastern North America, with a mean infestation rate of 0.21 ? 0.04 (mean + SE, n = 11 surveys) immature flies per spittlebug nymph. In the Chicago area it also occurs on Clastoptera proteus Fitch nymphs with a mean infestation rate of 0.04 ? 0.01 (mean ? SE, n = 24 surveys) immature flies per nymph. Fly larvae do not appear to damage spitlebug nymphs and nymphs do not appear to resist association with larvae. Clastoptera obtusa field-reared with Cladochaeta inversa larvae were not significantly smaller or more susceptible to mortality than maggot-free controls. There were no significant size correlations between fly puparia and Clastoptera obtusa adults reared from the same spittle mass. Enzyme electrophoresis gave no evidence for incipient speciation based on host specificity, but revealed a single case (among 32 tests on 19 specimens) in which a fly larva appeared to have ingested Clasoptera proteus tissue. Cladochaeta inversa may be intermittently parasitic, with nymphal hemolymph occasionally supplementing direct ingestion of spittle-borne nutrients in a predominantly commensal relationship.

Isolation of Amitriptyline and Nortriptyline from Fly Puparia (Phoridae) and Beetle Exuviae (Dermestidae) Associated with Mummified Human Remains

Abstract The use of anthropophagic fly larvae (maggots) as alternative toxicological specimens is well documented in the entomological and forensic science literature. Detection of various toxins and controlled substances in insects found on decomposing bodies has contributed to the assessment of cause/manner of death. With the development of hair extraction technologies, attention has recently focused on the analysis of chitinized insect remnants which are frequently encountered with mummified/skeletalized remains. In such cases, the standard toxicological specimens are often absent. Herein, we report the first detection of drugs from chitinized insect tissues.

Inundative Releases of Pteromalid Parasitoids (Hymenoptera: Pteromalidae) for the Control of Stable Flies, Stomoxys Calcitrans (L.) (Diptera: Muscidae) at Confined Cattle Installations in West Central Nebraska

Fly pupal parasitoids, primarily Muscidifurax raptor Girault and Sanders and Spalangia nigroaenea Curtis, purchased from commercial insectaries, failed to reduce numbers of stable fly, Stomoxys calcitrans (L.), significantly despite weekly releases of high numbers at one feedlot and one dairy during 1990 and a different feedlot and dairy in 1991. Parasitoid emergence from stable fly puparia were not significantly greater in the confinements where releases were made compared with confinements where no releases were made. The level of parasitism increased at all four confinements during and following parasitoid releases. Shipments of parasitoids contained neither the number requested or the species purity that had been anticipated. Both quantity and quality of parasitoids improved the second year of the research. The most numerous naturally occurring parasitoid species were also present at a new, relatively isolated feedlot by mid-July.

Intake and Efficacy of Methoprene and Stirofos Mineral Blocks for Control of Horn Flies (Diptera: Muscidae) on Pastured Beef Cattle

Pastured herds of Shorthorn beef cattle, Bos taurus L., in western Minnesota were treated with different insecticidal mineral blocks during the summers of 1990 and 1991. Treatments were noninsecticidal blocks (MoorMan’s 646-B Special Range Mineral Block A), 0.02% methoprene blocks (MoorMan’s 650-B), and 0.5% stirofos blocks (Sweetlix). Mineral intake was monitored once or twice per wk. To evaluate efficacy, identified animals from the three herds were commingled for 18 h in one pasture to allow naturally occurring horn flies, Haematobia irritans irritans (L.), to oviposit in the animals’ dung pats. Just before adults emerged, horn fly puparia were extracted to assess the effects of the insecticidal minerals on the developing flies. Intake of all three blocks varied substantially among weeks but most often exceeded prescribed rates. Methoprene blocks consistently increased pupal mortality, but offsetting increases in pupal densities negated effectiveness. Stirofos blocks did not increase larval mortality. Neither insecticidal block effectively prevented within-pasture production of horn flies under field conditions.

Hessian Fly (Diptera: Cecidomyiidae) Control by Compression of Hay for Export to Japan

Laboratory tests showed that significantly more pressure is required to destroy Hessian fly, Mayetiola destructor (Say), puparia with a volume of ≥4.0 mm3 than puparia with a volume of ≤3.4mm3. About 0.21 kg/cm2 of pressure destroyed all puparia. Compression of hay in commercial compressors with 42 or 72 kg/cm2 of pressure caused significant reductions in survival of Hessian fly puparia to the adult stage compared with the controls in standard bales of timothy, Phleum pratense; alfalfa, Medicago sativa; oat, Avena sativa; Sudan grass, Sorghum bicolor sudanensis; Bermuda grass, Cynodon dactylon hays; and rye straw, Secale cereale . Mortality ranged from 75.1 to 95.4% and was significantly increased by 72 versus 42 kg/cm2 of pressure on the bales. Compression with 42 or 72 kg/cm2 of pressure showed the same level of control in the four comers and middle positions of the front, middle, and back sections of the bale except that fewer insects survived to the adult stage in the middle position of the bale when compressed with 72 kg/cm2 of pressure. Compression of hay has potential as a single quarantine treatment for hay exported to Japan.

Plant and arthropod remains from the palaeo-Eskimo site on Qeqertasussuk, West Greenland

Samples from the excavation of a palaeo-Eskimo site, settled ca. 3900~3100 14C yrs BP on a raised beach, were analyzed for pollen and botanical and entomological macro-remains. In the dwelling area the original vegetation of grasses and Saxifraga spp. was covered by thick culture layers; under the midden Elymus mollis formed the original vegetation. During short uninhabited periods different grasses dominated. Following the termination of the habitation a mossy heath spread over the area. The sediments contained abundant well-preserved fragments of insects and other arthropods. Besides oribatid mites, spiders and fly puparia, remains of beetles arcpredominant. Micralymma brevilingue plays a prominent role, but also Simplocaria metallica, Byrrhus fasciatus and the heteropteron Nysius groenlandicus are fairlynumerous. A former warm period is indicated by the finds of species at or well north of their present northern limit. The succession of arthropod assemblages agrees with the palaeobotanical andarchaeological evidences. The fauna indicates the transition from typical arctic conditions: few species and low density, to stages with much higher diversity and density following fertilization, but also to stages of inferior conditions for plants and insects as a result of intensive human activity. A lake pollen diagram shows that after a short pioneer zone first Salix glauca, then ca. 6400 14C yrs BP. Betula nana immigrates. Shortly before 3000 BP more cool/humid conditions are indicated in accordance with the general trend in the Holocene climatic development of West Greenland, which is briefly discussed and summarized.

Hessian Fly (Diptera: Cecidomyiidae) Control by Hydrogen Phosphide Fumigation and Compression of Hay for Export to Japan

A multiple-quarantine treatment of compression and hydrogen phosphide fumigation (60 g/28.3 m3 for 7 d at > 10°C) was developed to control Hessian fly, Mayetiola destructor (Say), in six species of hay exported to Japan. The hay included timothy, Phleum pratense; alfalfa, Medicago sativa; oat, Avena sativa; Sudan grass, Sorghum bicolor sudanensis; Bermuda grass, Cynodon dactylon; and rye straw, Secale cereale . Commercial hay compressors configured to produce 72 and 80 kg/cm2 of pressure caused 93 and 97% mortality of Hessian fly puparia in bales held for 7 d in freight containers, respectively. Hydrogen phosphide fumigation of compressed bales significantly increased the mortality of puparia that survived compression in the bales. The total number of Hessian fly puparia tested and insect mortality for all species of hay was 255,191 and 99.940%, respectively, based on the number of puparia in wheat seedlings, and 105,763 and 99.855%, respectively, based on the number of puparia reared to the adult stage in laboratory controls. In total, 153 puparia survived hay compression and fumigation and were reared to the adult stage. The extraordinary number of insects tested in our large-scale tests would not occur in export-quality hay, and mortality would be increased by postharvest hay handling procedures. Hay compression and hydrogen phosphide fumigation can be used to control Hessian fly in a multiple-quarantine treatment and to maintain quarantine security levels required by regulatory agencies for hay exported to Japan.

Utilization of Freeze-killed House Fly and Stable Fly (Diptera: Muscidae) Pupae by Three Pteromalid Wasps

Utilization of freeze-killed house fly, Musca domestica L., and stable fly, Stomoxys calcitrans L., pupae for development by the pteromalid parasitoids, Muscidifurax zaraptor Kogan and Legner, Pachycrepoideus vindemiae (Rondani) and Spalangia nigroaenea Curtis was investigated. All three species of parasitoids used both fly species as hosts. Parasitoid emergence from house fly and stable fly puparia was not significantly different for M. zaraptor and P. vindemiae. However, emergence of S. nigroaenea was significantly higher from house fly puparia than from stable fly puparia. When given a choice, all three pteromalid species preferred ovipositing on house fly pupae, as indicated by parasitoid emergence. Parasitoid emergence from house fly puparia comprised ca. 75, 58 and 90% of the total combined emergence from house fly and stable fly puparia for M. zaraptor, P. vindemiae and S. nigroaenea, respectively. For M. zaraptor, the proportion of female progeny from house fly puparia (ca. 60%) was significantly higher than that from stable fly puparia (ca. 47%). The proportion of females from house fly and stable fly puparia for P. vindemiae and S. nigroaenea was not significantly different.

Parasitization of Helicoverpa zea (Lepidoptera: Noctuidae) by Palexorista laxa (Diptera: Tachinidae): Influence of Host Developmental Stage on Host Suitability and Progeny Production

Palexorista laxa (Curran) (Diptera: Tachinidae) successfully parasitized 2nd through 5th instars and prepupal Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) in the laboratory. Percent successful parasitization (that which resulted in the production of adult parasitoid progeny) increased with host developmental stage, reaching 97% in 5th instars, but fell to 75% in prepupae. The mean number of fly puparia and adults produced per successfully parasitized larva was greatest in 5th instar hosts, reaching 7.8 ± 0.6 (SEM) and 5.5 ± 0.4, respectively. The sex ratio of adult parasitoid progeny per host larval stadium was variable. Host favorability indices were calculated for each host stadium, and was highest in 5th instars. This index allows a direct comparison of the overall impact and reproductive potential of P. laxa attacking hosts of varying developmental stages.

The Phenology of the Native Dung Beetle Onthophagus-Australis (Guerin) (Coleoptera, Scarabaeinae) in South-Eastern Australia

Onthophagus australis (Guerin) is predominantly univoltine at two sites in south-eastern Australia, with Peaks Of activity in spring when most oviposition takes place, and in autumn when the new generation emerges. It overwinters mainly in the adult stage, and populations decline during summer droughts. The optimum temperature for oviposition is between 20 and 25-degrees-C, and the beetle produces food balls intermittently throughout life. The threshold temperature for development was estimated to be 5.2-degrees-C, and 1612 day-degrees (degrees-C) are required for development from egg to adult. In the laboratory, 100 beetles in a 1-L dung pad are able to reduce bush fly survival by 74%, and reduce the size of the fly puparia by 18%. In spring, when bush flies first build up their populations in the field, numbers of 0. australis did not often reach 100 per pad, thus limiting their usefulness for the biological control of the bush fly.

Greenbug and Hessian Fly Control in Winter Wheat with Insecticide-Treated Seed, 1991

Abstract Wheat seed treated with NTN 33893 (imidacloprid) was evaluated for greenbug and Hessian fly control in winter wheat planted 26 Oct in Cooke Co., TX. In Trial 1, Di-Syston 15 G was used as a standard treatment and applied with electric-driven Gandy boxes mounted on the wheat drill. In Trial 2, one rate of NTN treated seed (250 g (AI)/100 kg seed) was mixed with an equal volume of seed treated only with Baytan (triadimenol) fungicide. Each treatment was replicated 3 times in a randomized complete block. Plots were 13.5 × 65 ft long (seeding rate: 80 lb/acre). Treatments were evaluated at 31, 115, and 154 d after planting (DAP) by recording the number of greenbug per ft of drill-row in 2-4 locations/plot. Wheat plants in 1 ft of drill-row were pulled from 2 locations in each plot 199 DAP and combined into a single sample. Fifty small tillers from each sample were dissected to record Hessian fly puparia. Plots were harvested using a combine with an 8-ft header.

Ovipositional Preference Exhibited by Musca sorbens (Diptera: Muscidae) to Feces of Cows Fed Different Rations

Preferential selection of fecal pats for oviposition by Musca sorbens Wiedemann from cows fed different rations was studied. Caged ovipositing M. sorbens were overwhelmingly attracted to feces from cows fed concentrated feed supplements over feces from cows fed only grass. Gravid flies showed restraint in ovipositing on feces from cows fed on grass when confined in insect cages for protracted periods with no other breeding media available. Weight of fly puparia reared from preferred feces was 46.7% greater than that of puparia from feces ignored by ovipositing flies at the same dairy. Fresh samples of cow fecal pats were classified as either attractive or unattractive to ovipositing M. sorbens based on the presence or absence of egg clusters and were analyzed for differences in crude protein content. Results showing similar crude protein content in both samples indicated that protein residues were not responsible for ovipositional preference. These studies suggested that (1) M. sorbens refrains from ovipositing unless specific odors from digestive residues of concentrated feed supplements in cow feces are present; (2) fecal odors attracting ovipositing M. sorbens are related to nutritional needs of fly larvae; and (3) odors from digestive residues other than protein may be responsible for this attraction.

Relationship between Fruit Phenology and Infestation by the Apple Maggot (Diptera: Tephritidae) in Utah

The apple maggot, Rhagoletis pomonella (Walsh), occurs commonly in black hawthorn in Utah, attacks tart cherry infrequently, and has generally failed to infest apples. This study investigated how the timing of fruit maturation might account for this pattern. Infestation of hawthorn at three sites in 1988 commenced when fruits were rapidly increasing in size and water content, and perhaps most significantly, when mean resistance to penetration of the fruit skin dropped below a threshold. Dissections of trapped females indicated that a significant fraction of flies possessed mature ovaries before oviposition occurred in hawthorn in the field. The importance of fruit toughness early in the season also was suggested by measurement of individual fruits in 1989; no fruit with a penetration resistance >60 kg/cm2 yielded a fly puparium. No puparia were obtained from three apple cultivars that were sampled from an unsprayed orchard adjacent to a densely infested hawthorn stand. When apples collected during the oviposition period in hawthorn were presented to caged flies, only the early-maturing cultivar was successfully infested. Penetration resistance of mid- and late-season cultivars remained high throughout the period of fly activity. These results suggest that flies that originate in hawthorn in Utah emerge too early to attack the dominant local cultivars of apple. In contrast, the timing of adult emergence is relatively late for infestation of cherry, which ripens well before hawthorn. In behavioral assays, fruit phenology had only a minor effect on fruit acceptance; ovipositing females were less likely to attempt oviposition in immature hawthorn or cherry fruits but failed to discriminate between nearly ripe and ripe fruits.

Effect of Temperature on Parasitism, Development, and Diapause of the Filth Fly Parasite, Urolepis rufipes (Hymenoptera: Pteromalidae)

The solitary pupal parasite Urolepis rufipes (Ashmead), a recent isolate from house fly and stable fly puparia in eastern Nebraska, was studied to evaluate its potential as a biological control agent for these fly species. Parasitism was highest at 25°C for two age classes of host pupae. Parasite-induced mortality attributed to host stinging, excluding emerged parasites, increased with temperature, and generally was significantly higher than parasitism. The number of emerging male to female parasites was about equal and males generally began emerging 1 d before females. Development was more rapid than for most other pteromalid parasites of filth flies requiring 10–15 d for first male emergence at 25°C. Apparent diapause was evident with this species and was activated by the temperature at which the developing progeny were subjected.

Laboratory studies on the biology ofSpalangia nigra [Hym.: Pteromalidae

At 21 °C,Spalangia nigra Latreille (Hymenoptera: Pteromalidae) averaged 29.3 days between exposure and emergence of 1st progeny from host house flies,Musca domestica L. (Diptera: Muscidae). At 27 °C, the average developmental time to 1st emergence was reduced to 26.6 days, and a majority of adult wasps emerged from host house fly puparia between 29 and 40 days postoviposition. The sex ratio of progeny ranged from 1.4 to 1.8 female-to-male, but all progeny of virgin females were male. Male wasps lived from 6.8–15 and females 11–17.8 days at 27 °C; honey as a food source increased longevity. No significant differences in parasitism byS. nigra were associated with host house fly pupal densities ranging from 1 to 200 pupae per female-male pair of wasps, but average percent parasitism decreased at host densities greater than 50. House fly pupae exposed to parasitism at ages ranging from 4 to 96 h did not differ in subsequent production of adult flies.S. nigra did not demonstrate preference for house flies or stable flies,Stomoxys calcitrans (L.) (Diptera: Muscidae) as hosts. The results of these studies indicate thatS. nigra may contribute significantly to previously unexplained mortality of house flies and stable flies.

Parasites of Face Flies (Diptera: Muscidae) in South Central Nebraska1

Field parasitism of the face fly, Musca autumnalis De Geer, by insect parasites and the nematode, Heterotylenchus autumnalis Nickle, was investigated in south central Nebraska. Four species of insect parasites were collected from face fly puparia: Aphaereta pallipes Say, Muscidifurax sp., Eucoila sp., and Aleochara sp. A. pallipes was found only during the first 4 wk of the study (6–24 June), whereas the other three parasites were intermittently found, at low levels, for the remainder of the study (24 June–26 September). Total seasonal insect parasitism averaged 4.3%. Seasonal parasitism by the nematode H. autumnalis averaged 5.8% and peaked at 18% on 9 September.

Field Parasitism of the Stable Fly (Diptera: Muscidae)1

Insect parasitism of the stable fly, Stomoxys caldtrans (L.), was studied at cattle farms for two seasons in central Missouri. Ten species of insect parasites were collected from stable fly puparia: Spalangia nigra Latreille, Spalangia nigroaenea Curtis, Spalangia endius Walker, Spalangia haematobiae Ashmead, at least two species of Muscidifurax (Pteromalidae), at least two species of Trichopria (Diapriidae), Diplazon laetatorius (F.) (Ichneumonidae), and a species of Aleocharinae (Staphylinidae). In addition, mermithid nematodes were collected from adult stable flies. The collection of S. haematobiae, D. laetatorius, and the nematodes constitute new parasitic associations for the stable fly. S. nigra was the dominant parasite of the stable fly during these studies. Rates of parasitism were low when averaged over the season, but occasionally exceeded 50% during July.

First Report of a Parasitic Fly (Diptera: Phoridae) from a Red Imported Fire Ant (Solenopsis invicta) Alate Female (Hymenoptera: Formicidae)

A number of phorid flies are known to parasitize various life stages of bees and wasps, including reproductives (Kistner 1982). Several genera of phorids are known or assumed to be parasitic on worker ants but not on reproductives (Borgmeier 1963; Borgmeier and Prado 1975). Williams (1980) summarized the known data on phorids attacking and parasitizing fire ants sens. str., Solenopsis (Solenopsis) spp., in South America. To date, only one species is definitely known to parasitize fire ant workers, although other species are assumed to be parasitic on fire ants (Williams 1980). None of these species are present in the United States (Borgmeier 1963). Fire ant colonies collected as part of our continuing survey for biological control agents of fire ants were processed by the methods given in Jouvenaz et al. (in press). One colony of Solenopsis invicta Buren, collected 5-Feb-85 on the road shoulder of BR-070, km 616, ca. 1/2 way between Caceres and Cuiaba, Mato Grosso, Brasil, in disturbed cerrado (arid tropical savanna), was found to contain an unidentified nematode (Jouvenaz et al. in press). During studies of the nematode, 200 adult workers, 200 worker pupae, 200 adult males, and 65 alate females (all that were present in the collection) were dissected, yielding one puparium of a phorid fly (identified by D. H. Habeck, Dept. Entomology and Nematology, University of Florida, Gainesville, FL) from one alate female (virgin queen). The first two body segments of the puparium were darkened and heavily sclerotized. Two large conspicuous horn-like structures were noted on the prothoracic segment, probably the prothoracic spiracles. The remainder of the puparium was white and unmelanized. No gross morphological alterations were noticed in the alate ant before dissection. After several months preservation in 70% ethanol, the unmelanized portion of the puparium cleared, revealing the partially developed pupa inside. The pupa had developed to the point of eye facet coloration but no other parts were melanized. Since fire ants are not routinely dissected as part of our survey in Brazil, a special effort was made to collect alate females from fire ant nests on a subsequent trip (February to March 1986). Alate females were found in 93 colonies. These were preserved in alcohol and dissected in the United States. Up to 20 alate females were dissected from each colony (total of 1,561). No fly puparia were found although an unidentified microsporidian disease and nematodes were found. This is the first report of a phorid fly parasitizing alate female ants of any species. This find raises the possibility that a species of phorid exists that may be good biological control agents for queens and alate females of fire ants, not just workers. The success of a biological control program for fire ants using parasitoids which affect only worker ants would not seem to hold much promise, because of the large numbers of workers in fire ant colonies (Markin et al. 1973). The possibility exists that this is an instance of mistaken parasitism by the fly. During mating flights, activity on the surface of fire ant mounds becomes very hectic and a phorid could attack an alate by mistake. All reported cases of attack on worker ants describe the ant as stunned (Williams 1980; Kistner 1982). An alate female which

Stabilization of mineralized and sclerotized puparial cuticle of muscid flies

Calcium, magnesium and phosphorus are the major mineral elements in puparial exuviae of the face fly, Musca autumnalis, house fly, M. domestica and stable fly, Stomoxys calcitrans, but they are 20–50 times more prevalent in face fly than in the other two species that sclerotize the puparium. Carbon and nitrogen are approx. 5 times more abundant in house fly puparia than in face fly puparia. Face fly puparia contain two and three-fold less total amino acids than the house fly and stable fly, respectively. β-Alanine is a major amino acid in puparial cuticle of the house fly and stable fly, but it is absent in the face fly. There is no significant difference in glucosamine (chitin) content between the three species. Dopamine is the major catechol detected in face fly puparial cuticle while N- β-alanyldopamine (NBAD) is 10 to 15 times more prevalent than other catechols such as dopamine, N-acetyldopamine (NADA), 3,4-dihydroxyphenylalanine (DOPA) and 3,4-dihydroxyphenylacetic acid (DOPAC) in house fly and stable fly puparial cuticles. The latter two species have 75 to nearly 200 times higher levels of extractable catechols than the face fly. At the onset of pupariation, dopamine and NBAD attain nearly equivalent titres in puparial cuticles of face fly and house fly, respectively. Dopamine subsequently decreases more than 40-fold in the face fly as the cuticle becomes stabilized, while NBAD continues to accumulate in the house fly. The house fly covalently incorporates about 150 times more catechols in the puparium than does the face fly. The force required to fracture house fly and stable fly puparia is about three-fold greater than that required to fracture face fly puparia of comparable thickness. However, the face fly puparium attains a strength comparable to those of house fly and stable fly puparia by significantly increasing its thickness. These results demonstrate that dipterans use both catecholamines and minerals for stabilization of puparial cuticle with the house fly and stable fly relying primarily on sclerotization and the face fly on mineralization.