Synchrony and impact ofAmitus hesperidum [Hym.: Platygasteridae] on its host,Aleurocanthus woglumi [Hym.: Aleyrodidae] in southern Florida

The synchrony of the citrus blackfly (CBF)Aleurocanthus woglumi Ashby and its parasitoidAmitus hesperidum Silvestri was studied in southern Florida.A. hesperidum adults emerge from 4th instar nymphs 160–300 thermal units after CBF adults. This insured excellent temporal synchronization between the parasitoids and the early CBF instars they prefer since egg to 3rd instar nymph in CBF takes 380 thermal units. AlthoughA. hesperidum parasitized only 29% of the surviving 4th instar CBF, it was the factor responsible for the observed decline in the CBF population level in southern Florida.     

Indian species of the genusMirufens [Hym.: Trichogrammatidae]

An account is given of 4 new species ofMirufens Girault:M. brevifuniculata Khan & Shafee, M.albiscutellum Khan & Shafee,M. magniclavata Khan & Shafee andM. longiclavata Khan & Shafee. A key to Indian species of the genusMirufens is also provided.     

Note on breeding the argentine stem weevilHyperodes bonariensis [Col.: Curculionidae] and its egg parasitePatasson atomarius [Hym.: Mymaridae]

Hyperodes bonariensis Kuschel underwent ovarial diapause from March to August in the Bariloche area in Argentina. Feeding on germinating seedlings ofTriticum aestivum L. andPoa annua L. in continuous dark induced the weevil for oviposition in 24 and 32 days, respectively. Breeding techniques are described forH. bonariensis and its parasitePatasson atomarius (Brethes).     

New fig insects [Hym.: Chalcidoidea] from India: Three torymids parasitic on agaonids

Two new species of fig wasps (Sycoscapter punctatus Abdurahiman & Joseph andSycobiella amplissima Abdurahiman & Joseph) parasitic onManiella delhiensis Abdurahiman & Joseph fromFicus amplissima Smith, and the female of a known species (Philotrypesis anguliceps Westwood) parasitic onBlastophaga quadraticeps Mayr fromFicus religiosa L. are described.     

On the identity and systematic position of the genusDirphys [Hym.: Aphelinidae]

Types have been examined of the aphelinid genusDirphys Howard (Type species,Mesidia mexicana Howard). It is found to be closely related toEncarsia Förster and related coccophagine genera. Hence its earlier placement in the subfamilyAphelininae sensu De Santis orAphytinae Jasnosh is considered untenable and, consequently, it is transferred to subfamilyCoccophaginae sensu De Santis.     

A review of haliday species ofMicroctonus [Hym.: Braconidae,Euphorinae]

A neotype based on aWesmael specimen is designated forMicroctonus aethiops (Nees).M. aethiops of authors is described asaethiopoides, new species. Lectotypes are designated forM. secalis (Haliday) andcerealium (Haliday). The namecerealium is suppressed as a synonym of the namesecalis and the types ofsecalis andbrevicollis (Haliday) are redescribed.     

Effect on waterhyacinth ofNeochetina eichhorniae [Col.: Curculionidae] combined withOrthogalumna terebrantis [Acari: Galumnidae]

Seven hundred mottled waterhyacinth weevils,Neochetina eichhorniae Warner, were released in a Fort Lauderdale, Florida, canal on a mat of waterhyacinth,Eichhornia crassipes (Mart.) Solms-Laubach. At the time of weevil release, the mat contained ca. 100 adult waterhyacinth mites,Orthogalumna terebrantis Wall-work/plant, and ca. 15 immature waterhyacinth mites/cm². Waterhyacinth weevil populations increased to ca. 4 adults and 5 larvae/plant after 50 weeks, and were unaffected by weather. Waterhyacinth mite populations reached a peak of ca. 840/plant after 16 weeks, at which time they were reduced in number by low temperatures. Decrease in size and density of waterhyacinth closely followed buildup of weevil populations, with petiole length decreasing by 35% and plant density reduced by 45% over a 50 week period. The phytopathogenic fungusAcremonium zonatum (Saw.) Gams., which causes zonate leaf spot disease of waterhyacinth, developed in waterhyacinth mite tunnels after the adult mite created an emergence hole, but was not observed in weevil feeding spots.     

Host discrimination byChelonus insularis [Hym.: Braconidae], telenomus heliothidis [Hym.: Scelionidae], andTrichogramma pretiosum [Hym.: Trichogrammatidae]

The ability of female parasitoids (Chelonus insularis Cresson,Telenomus heliothidis Ashmead, andTrichogramma pretiosum Riley) to distinguish between parasitized and unparasitized tobacco budworm,Heliothis virescens (F.), eggs was determined in laboratory studies. All 3 species were relatively efficient at detecting eggs that were previously parasitized by conspecific females.T. heliothidis andT. pretiosum were able to discriminate on the basis of external examination of host eggs, whereasC. insularis appeared to examine hosts internally as well as externally. In interspecific tests, no species readily rejected eggs parasitized by the other 2 species.     

Parasitization of 6 lepidopteran cotton pests byChelonus blackburni [Hym.: Braconidae]

When eggs of 6 species of lepidopteran cotton pests were offered toChelonus blackburni Cameron, all were parasitized except those of the saltmarsh caterpillar,Estigmene acrea (Drury). However, the parasite did not distinguish between parasitized and unparasitized eggs, so superparasitization was common. Of the 5 accepted species (pink bollworm,Pectinophora gossypiella (Saunders), cotton bollworm,Heliothis zea (Boddie), tobacco budworm,Heliothis virescens (F.), cabbage looper,Trichoplusia ni (Hübner), and beet armyworm,Spodoptera exigua (Hübner), pink bollworms and cotton bollworms were the most suitable hosts. When all 5 species were offered, the order of preference was as follows: pink bollworms = cabbage loopers > cotton bollworms > tobacco budworms > beet armyworms. In paired preference tests the parasite consistently preferred pink bollworms.     

The introduction and establishment of parasites of citrus blackfly,Aleurocanthus woglumi in Florida [Hem.: Aleyrodidae]

Three species of laboratory-reared parasites of citrus blackfly,Aleurocanthus woglumi Ashby, were released at Fort Lauderdale, Florida in 1976 following discovery of this citrus pest in residential properties there.Amitus hesperidum Silv. andProspaltella opulenta Silv. were recovered 6 weeks after release and sharp increases in the rate of parasitism were observed throughout the season. Seven months after the initial release, 100% parasitism of citrus blackfly pupae was observed at some release sites, and 95% of the original release sites were found positive for the parasite. Observations after 1 year showed significant levels of parasitism over a large area. The rapid establishment and increase of these parasite species indicate that environmental conditions and the host at Fort Lauderdale are suitable for these species and that they may well provide control of the pest.     

Geographical distribution ofAphidiidae [Hym.] imported to California for biological control ofAcyrthosiphon kondoi andAcyrthosiphon pisum [Hom.: Aphididae]

A survey forAcyrthosiphon kondoi Shinji and its insect enemies was conducted in 1976–1977 in Afghanistan, Belgium, Czechoslovakia, Greece, Iran, Israel and Maroc. The search was concentrated in areas having cultivated species ofMedicago. A. kondoi was found only in Afghanistan, and in Iran. It was not found inMedicago-growing areas west from Iran, but it has been reported from India and Japan. Aphidius ervi Haliday,Aphidius urticae group,Praon barbatum Mackauer andAphidius smithi Sharma & Rao, were reared fromA. kondoi constituting new parasite records. New parasite and locality records were also found forA. urticae group,A. smithi andP. barbatum onAcyrthosiphum pisum (Harris). In laboratory trials, all cultures of parasitesA. ervi andP. barbatum readily parasitized and reproduced onA. kondoi onLens esculenta Moench. Cultures ofA. urticae group andA. smithi oviposited on, but did not complete development of immatures in,A. kondoi onL. esculenta. Hyperparasites identified as species includedAsaphes suspensus (Nees),Asaphes vulgaris Walker,Aphidencyrtus aphidivorus (Mayr),Dendrocerus breadalbimensis (Kieffer),Dendrocerus carpenteri (Curtis), andPachyneuron aphidis (Bouche). Available data suggest the origin of distribution ofA. kondoi may be Central Asia, and that populations ofA. ervi may be most suitable for colonization programs againstA. kondoi.     

Interactions betweenPleolophus basizonus andLophyroplectus luteator [Hym.: Ichneumonidae], two parasites ofNeodiprion sertifer [Hym.: Diprionidae]

Females ofPleolophus basizonus (Gray.) show a very strong avoidance of cocoonedNeodiprion sertifer (Geoff.) prepupae in which there are eggs, larvae or prepupae ofLophyroplectus luteator (Thunb.). When multiparasitism does occurP. basizonus is the successful competitor but adults are much smaller than those from hosts that were not multiparasitized.     

Parasites ofSpodoptera exigua,S. eridania [Lep.: Noctuidae] andHerpetogramma bipunctalis [Lep.: Pyralidae] collected fromAmaranthus hybridus in field corn

Three species of lepidopterous larvae were collected fromAmaranthus hybridus L. growing in field corn during 1975 and 1976 at Hastings, Florida.Spodoptera exigua (Hubner) was the predominant species in May.Spodoptera eridania (Cramer) was predominant in June andHerpetogramma bipunctalis (F.) in July and August. Nine native species of parasites, representing theBraconidae, Eulophidae, Ichneumonidae andTachinidae, emerged from these larvae.Meteorus autographae Muesebeck emerged from bothS. exigua andS. eridania. TheTachinidae, Winthemia rufopicta (Bigot),Eucelatori rubentis (Coquillett) andLespensia sp., emerged from mixtures ofS. exigua andS. eridania. Apanteles marginiventris (Cresson),Temelucha sp., andChelonus texanus Cresson emerged from bothS. exigua andH. bipunctalis larvae, andEuplectrus platyhypenae Howard andOphion sp. emerged fromS. eridania. All the species of parasites from the lepidopterous larvae that feed onAmaranthus hybridus are also reported as parasites ofS. frugiperda, a serious pest of corn. Therefore these larvae onA. hybridus may be a source of the parasites found attackingS. frugiperda.     

Notes on the biology ofOdynerus dilectus [Hym.: Eumenidae], a predator of the alfalfa weevil,Hypera postica [Col.: Curculionidae]

We describe the nest construction and architecture, and the prey collection and storage behavior ofOdynerus dilectus Saussure, a ground-nesting eumenid wasp of North America that exclusively utilizes weevil larvae of the genusHypera as prey. This species may have potential as a biological control agent of alfalfa and clover weevils in the genusHypera because of its rapid collection of weevil larvae, its gregarious nesting habit, and the apparent ease with which individuals can be transplanted. Other European congeners have many similar characteristics. The potential for adverse interactions betweenO. dilectus andBathyplectes curculionis (Thomson), a parasite ofHypera, is discussed.     

A method for the extraction ofSitona [Col.: Curculionidae] eggs from soil and occurrence of a mymarid [Hym.: Chalcidoidea] in the mediterranean region

A simple method of extracting the eggs ofSitona spp. from the soil is described. From 1973 to 1975 it was used in Spain, France, Italy and Greece to collect in good condition the eggs ofSitona humeralis Stephens, a weevil which has recently become a major pest in Australia. A mymarid parasitoid provisionally identified asPatasson lameerei Debauche emerged from these eggs apparently unaffected by the extraction method.     

Affects of two cotton varieties on levels of boll weevil parasitism [Col.: Curculionidae]

The cotton plant has a profound affect on the behavior and ability of parasites to successfully attack the boll weevil,Anthonomus grandis Boheman. The most important native parasite of the boll weevil,Bracon mellitor Say, prefers to oviposit on Frego bract cotton rather than normal bract cotton. An imported parasite,Heterolaccus grandis Burks prefers ovipositions on normal bract cotton rather than Frego.     

Notes on the taxonomy and nomenclature ofAphidius species [Hym.: aphidiidae] parasitic on the pea aphid in North America

A brief discussion is given on the taxonomy, nomenclature, distribution, and hosts of severalAphidius species attacking the pea aphid,Acyrthosiphon pisum (Harris), in North America.Aphidius pisivorus Smith,A. smithi S. & S. R., andA. ervi Hal. are considered distinct species attacking the pea aphid;A. nigripes Ashm. is shown not to be a parasite of the pea aphid;A. pulcher Baker is placed in synonymy withA. nigripes. Distinguishing characters for each species are illustrated.     

Some aphid parasites [Hym., Aphidiidae] from Spain

This paper is a result of identification of aphid parasite material occasionally collected by Prof.G. Remaudière in Spain. Among the four species recognized, three are new to Spain (·) and one of them is a new species of the genusLysiphlebus (L. hispanus Starý). The host of the new species belongs to a new suggenus ofProtaphis: Absinthaphis Remaud. restricted to some steppe species ofArtemisia.     

TheSitona [Col.: Curculionidae] species occurring onMedicago and their natural enemies in the Mediterranean region

TwentySitona species were found in the Mediterranean region during surveys on 17 volunteer and/or cultivated species ofMedicago. The distribution of the weevils was analyzed using the 3 concepts of abundance, constancy and dominance. EightSitona species were consistently recorded on lucerne and medics; of these, 3 were “constants” and only 2,S. humeralis Stephens andS. lineatus Linnaeus, also “dominants” in the sites investigated. Sixteen species of natural enemies were identified (table 4), including 3 egg predators, 3 egg parasitoids, 1 entomogenous fungus, 2 nematodes and 5 parasitoids of adult weevils. The effect of each organism on theSitona population numbers was slight, not exceeding in most cases an average mortality of 15%. At high host densities however, the braconidMicroctonus aethiopoides Loan which is the preponderant parasitoid, caused estimated mortalities up to 80% during a single weevil generation. Noticeable changes in the relative importance of the natural enemies were observed between the areas surveyed, with onlyM. aethiopoides and the mymarid egg parasitoidPatasson lameerei Debauche occurring widely. Moroccan, French and Greek strains of these 2 parasitoids were forwarded to Australia for the biological control ofS. humeralis there.     

Determination of host range in relation to systematics forPeristenus stygicus [Hym.: Braconidae], A parasitoid ofMiridae

Peristenus stygicus Loan develops inMirinae speciesLygus hesperus,Knight,L. lineolaris, (Palisot de Beauvois) andPolymerus basalis (Reuter),Orthotylinae speciesLabopidicola geminata (Johnston),Phylinae speciesPseudatomoscelis seriatus (Reuter) and partially develops in the mirineDichrooscytus sp. The parasitoids attackMicrophylellus maculipennis (Knight) (Phylinae) and another orthotyline species, but do not develop in these.Taedia johnstoni (Knight) (Mirinae), 2 species ofBrycorinae and 3 species ofLygaeidae are not acceptable as hosts. Olfactometer studies show the parasites are significantly more attracted to lygus nymphs whenPhaseolus vulgaris L. is present than either the nymphs or bean alone. Host color, mobility, size, previously infested plant material, and host plant species are rejected as host selection criteria.