Stimulation of oviposition and successful rearing ofTelenomus heliothidis [Hym.: Scelionidae] on nonhosts by use of a host-recognition kairomone

Through use of a recognition kairomone, the parasitoidTelenomus heliothidis Ashmead is induced to oviposit and successfully develops in nonhost eggs.T. heliothidis successfully develops in the eggs ofSpodoptera frugiperda (Smith) andPhthorimaea operculella Zeller, but fails to develop in eggs ofAnthonomus grandis Boheman. Both sexes of the parasitoid are produced from the nonhosts, and development time is the same as in a natural host such asHeliothis virescens F. The use of recognition kairomones could be of great use in artificial rearing of nongeneralist parasitoids suchT. heliothidis.     

Interspecific competition among endoparasitoids of tobacco budworm larvae [Lep.: Noctuidae]

The ability of female larvae endoparasitoids [Microplitis croceipes Cresson:Cardiochiles nigriceps Viereck andCumpoletis sonorensis (Carlson)] to distinguish between unparasitized tobacco budworm,Heliothis virescens (F.), larvae andH. virescens larvae parasitized by the egg-larval parasitoidChelonus insularis,Cresson, was determined in laboratory studies. The 3 species of larval endoparasitoid females did not appear capable of distinguishing between unparasitized andC. insularis parasitized larvae resulting in multiple parasitoidism. The results of the ensuing competition between the 3 species for possession of the host demonstrated that bothC. sonorensis andM. croceipes were intrinsically superior toC. insularis. Both larva endoparasitoids destroyed the olderC. insularis larvae by physically attacking the latter. The presence ofC. insularis larvae in the host was found to prevent the hatch of compeatingC. nigriceps eggs through physiological suppression. The results show that the early attack of a host, as in the egg-larval parasitoid habit, is not necessarily advantageous.     

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.     

Regulation of host larval development by the egg-larval endoparasitoidChelonus insularis [Hym.: Braconidae]

In laboratory studies the effect of parasitism by the egg-larval endoparasitoidChelonus insularis Cresson on the resulting larvae of 2 host species,Heliothis virescens (F.) andSpodoptera ornithogalli Guénée) were determined by comparing daily measurements of larval weights. Growth of parasitized larvae of both host species was slower than growth of unparasitized larvae. Injections of fluids from the female parasitoid's calyx or poison gland intoH. virescens eggs retarded subsequent larval growth. However, a combination of fluids from these 2 organs produced the most significant reduction in the host larval growth rate. The growth reducing factor(s) was also effective when injected into 5-day-old host larvae.     

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.     

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.     

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.     

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.     

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.     

Establishment of the exotic parasiteTetrastichus haitiensis [Hym.: Eulophidae] and recovery of a newTrichogramma [Hym.: Trichogrammatidae] from root weevil egg masses in Florida

The exotic root weevil egg parasite,Tetrastichus haitiensis Gahan, imported from Puerto Rico and released in Florida between 1969 and 1971, was found established on citrus root weevil egg masses in 1978 near Oakhill, Florida. It was also recovered there from field-collected weevil egg masses from June to August 1978 and from citrus bouquets containing egg masses placed in the grove during July and August 1978. In addition, a new species ofTrichogramma was discovered. In the laboratory, this species parasitized egg masses of 4 species of weevils that attack citrus in Florida. These areDiaprepes abbreviatus (L.),Pachnaeus litus (Germar),P. opalus (Olivier) andArtipus floridanus Horn.     

Mortality factors of satin moth,Leucoma salicis [Lep.: Lymantriidae], in aspen forests in Maine

Natural control agents of the satin moth,Leucoma salicis (L.) were examined in 2Populus grandidentata Michaux stands. Highest mortality occurred in overwintering larvae, with the causal agents 2 fungi,Paecilomyces sp. andHirsutella gigantea Petch, a factor causing death symptomatic of a pathogen, the parasiteEupteromalis hemipterus (Walker) and death from unknown causes. Mortality fromPaecilomyces sp. andE. hemipterus was reduced where overwintering sites were covered with burlap cloth. Parasites recovered from larvae and pupae included the braconidsApanteles melanoscelus (Ratzeburg) andMeteorus versicolor (Wesmeal), the ichneumonidCoccygomimus pedalis (Cresson), the tachinidsCompsilura concinnata (Meigen),Carcelia laxifrons Villeneuve,Tachinomyia variata Curran, and the sarcophagidsSarcophaga aldrichi Parker andAgria housei Shewell. Larval and pupal predators included the carabidCalosoma frigidum Kirby, pentatomids, and birds, particularly black-billed cuckoos,Coccyzus erythrophthaimus (Wilson). Eggs were parasitized by the scelionidTelenomus prob.californicus Ashmead and the trichogrammidTrichogramma minutum (Riley). Predators of adult satin moths included the hermit thrush,Hylocichla guttata (Pallas), and pentatomid bugs.     

Biological control of the beanfly,Ophiomyia phaseoli [Dipt.: Agromyzidae], byOpius spp. [Hym.: Braconidae] in the Hawaiian Islands

Attention is drawn to the transfer of the beanfliesMelanagromyza phaseoli (Tryon) andM. spencerella Greathead to the genusOphiomyia Braschnikov bySpencer (1973). The confusion over the nomenclature of theOpius spp. parasites is discussed and it is shown that the namesO. phaseoli Fischer andO. importatus Fischer should be used. Their introduction into Hawaii and establishment is briefly discussed in relation to their effectiveness as biological control agents. It is shown that they show a high degree of consistency of parasitism which has resulted in an acceptable degree of control ofOphiomyia phaseoli although there is no evidence that they act in a density dependent manner.     

Parasites of bark beetles [Col.: Scolytidae] on pine and cypress in Israel

Ten species of hymenopterous parasites were reared from logs of pine and cypress, naturally infested with 5 species of bark beetles,viz., Orthotomicus erosus Woll.,Pityogenes calcaratus Eichh., andTomicus destruens Woll. — on pine;Phloeosinus armatus Reitt. andP. aubei Perris — on cypress, in Israel. The parasites were:Dendrosoter chaenopachoides Rusch,D. hartigii (Ratz.),D. middendorfi (Ratz.),D. protuberans Nees (Braconidae), Eurytoma morio Boheman (Eurytomidae), Cerocephala eccoptogastri Masi,Heydenia pretiosa F?rster,Metacolus unifasciatus F?rster,Rhaphitelus maculatus Walker andRoptrocerus xylophagorum (Ratz.) (Pteromalidae). The most common wereM. unifasciatus on pine and cypress,D. chaenopachoides andR. xylophagorum on pine, andD. protuberans on cypress, occurring in samples collected during most seasons. Less common wasE. morio, which was reared from both conifers.D. middendorfi was found on pine, and only during winter. The other species were found only occasionally.     

Searching and ovipositional behavior ofAmitus hesperidum [Hym.: Platygasteridae] andEncarsia opulenta [Hym.: Aphelinidae] parasitoids of the citrus blackfly [Hom.: Aleyrodidae]

Searching behavior ofAmitus hesperidum Silvestri andEncarsia opulenta (Silvestri) for immatureAleurocanthus woglumi Ashby was similar. Both parasitoids moved unidirectionally until they encountered a host aggregation at which time they changed to a pattern of short walks with numerous turns. Parasitoid ovipositor insertion was generally at midbody between the host sternites and tergites.Amitus hesperidum females showed a significant preference for 1st instar hosts, have an ovipositional marker, do not feed on exudates from ovipositional wounds (host feed), and have significantly shorter ovipositional times and adult life spans thanE. opulenta which showed a significant preference for 2nd instar hosts, lack an ovipositional marker, and host feed.Encarsia opulenta females showed a significant preference for hosts previously parasitized byA. hesperidum but the reverse was not true. The average number of hosts parasitized by females of both parasitoid species was uninfluenced by the previous presence of the other parasitoid species on the same leaf.     

A revision ofTaraxacum sect.Piesis (Compositae)

On the basis of allozyme and cultivation data, and of additional herbarium material, a taxonomic and nomenclatural revision ofTaraxacum sect.Piesis A.J. Richards exKirschner et?těpánek is provided. The section is made up of halophilous, sexually reproducing taxa. InT. stenocephalum Boiss. etKotschy,T. pindicum Kirschner et?těpánek, sp. nov., andT. perenne Kirschner et?těpánek, sp. nov., a tetraploid chromosome number has been recorded, representing the only known case of sexuality at the tetraploid level in the genus. The complex ofT. stenocephalum, includes some geographically and morphologically extreme populations treated as subspecies: subsp.gumusanicum (Soest)Kirschner et?těpánek, comb. nov., subsp.magnum Kirschner et?těpánek, subsp. nov., and subsp.daralagesicum (Schischk.)Kirschner et?těpánek, comb. nov. In addition toT. bessarabicum (Hornem.)Hand.-Mazz., a widely distributed Eurasian species,T. stenocephalum, a complex centred in Transcaucasia and Anatolia, andT. pachypodum H. Lindb., a North African endemic, four new species are described:T. salsum Kirschner et?těpánek, sp. nov., a diploid endemic confined to E Crimea,T. perenne Kirschner et?těpánek, sp. nov., a tetraploid sexual species known only from SW Crimea,T. pindicum Kirschner et?těpánek, sp. nov., a remarkable tetraploid endemic to the Pindos Mts., Greece, andT. salsitatis Kirschner, ?těpänek etYirdirimli, sp. nov., an Anatolian diploid species. Furthermore, a hybrid betweenT. salsum andT. bessarabicum from Crimea (documented on the basis of allozyme data elsewhere) is given a binomial,T. xmesohalobium Kirschner et?těpánek, nothosp. nov.     

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.     

Effect of hosts and parasite density on the egg parasiteTrichogramma pretiosum [Hym.: Trichogrammatidae]

When females ofTrichogramma pretiosum Riley were confined with host eggs at a density of 2/150 eggs, they produced 12 times more female progeny on eggs of potato tuber moth than on eggs ofHeliothis armigera (Hübner) and 13,6 times more on eggs ofSitotroga cerealella (Olivier) than on eggs ofHeliothis. At a density of 4/150 eggs, the correspondent figures were 13 and 8 times. The percentage emergence fromHeliothis eggs was from 0,29 to 0,14 times as great as from tuber moth orSitotroga. From 15 to 140 times more runts were observed amongTrichogramma fromHeliothis eggs than among those from tuber moth eggs and 8 times more thant among those fromSitotroga eggs. This may explain the low recoveries in South Africa ofT. pretiosum in eggs ofH. armigera collected in cotton fields after mass liberation of the parasite. An increase in parasite density from 1/300 eggs to 16/300 eggs resulted in a decrease from 29 to 14 in the hosts parasitised per female, a decrease in the proportion of female progeny from 72 to 39%, a decrease in the female progeny per female from 18 to 4,8, and an increase in the proportion of runts from 2,4 to 12,4%. It is suggested that in mass culture ofTrichogramma unduly high parasite densities should be avoided in order to reduce the effect of mutual interference and raise the output of female progeny.     

Effects ofBathyplectes curculionis andBathyplectes anurus [Hym.: Ichneumonidae] on the growth and development ofHypera postica [Col.: Curculionidae]

Observations, linear measurements, dissections, and histological preparations were made of parasitized and nonparasitized larvae of the alfalfa weevil,Hypera postica (Gyllenhal), on a daily basis. The observed developmental period lasted from 24 h after oviposition byBathyplectes curculionis (Thomson) orBathyplectes anurus (Thomson) until parasite larvae emerged from their hosts. Adult and larval parasites significantly altered growth and development ofH. postica larvae.B. curculionis andB. anurus caused 24 and 29% greater premature mortality in young host larvae than that observed in the unparasitized controls. Rate of development for parasitized larvae during the 1st 12 days was essentially the same as for nonparasitized larvae. Nonparasitized larvae reached maximum size in 17–18 days, whereas larvae parasitized byB. curculionis andB. anurus required 14–21 and 19–22 days, respectively. Larvae parasitized byB. curculionis are smaller in overall lengths, widths and head capsule widths than nonparasitized larvae and those parasitized byB. anurus.     

The observed sex ratio ofPediobius foveolatus [Hym.: Eulophidae] in field populations ofEpilachna varivestis [Col.: Coccinellidae]

Larvae ofEpilachna varivestis Mulsant, parasitized byPediobius foveolatus (Crawford), were collected in soybean fields in Maryland during 1975. AdultP. foveolatus emerging from the larvae were sexed and counted. The ratio of males to females increased as the availability of food within the host decreased. This information is useful in development of exponential models predicting hostparasite interactions.