Surveys For Biological Control Agents Research Articles

Archernis humilis (Swinhoe) (Lepidoptera: Crambidae) Rediscovered Feeding on Skunk Vine (Paederia foetida L.) in Southeast Asia

Archernis humilis (Swinhoe) (Lepidoptera: Crambidae) has previously been recorded only from India, and nothing has been reported about its biology or immatures. It was recently discovered during surveys for biological control agents against Paederia foetida L. (Rubiaceae) or skunk vine, and this represents the first report of the food plant. Archernis humilis was not sufficiently host specific to be considered as a biological control agent of P. foetida because it showed strong preference for other Paederia species and oviposited on P. ciliata, a Mexican endemic. With considerable new material available from a laboratory colony, we describe the adult morphology in greater detail, including internal genitalic structures of both sexes for the first time. We also provide an image of the egg and describe the larvae and pupae. We discuss the currently known distribution and expansion to China and Thailand. We designate as a lectotype a specimen from Khasia Hills, India. A phylogenetic analysis shows that Archernis is closely related to Trichaea Herrich-Schäffer and Prophantis Warren (Crambidae).

Host Plants and Natural Enemies of Rugose Spiraling Whitefly (Hemiptera: Aleyrodidae) in Florida

The rugose spiraling whitefly, Aleurodicus rugioperculatus Martin (Hemiptera: Aleyrodidae), is a polyphagous pest that has caused significant damage in the Florida landscape. Various plants have been identified as primary hosts in affected areas. Rugose spiraling whitefly was confirmed in 22 counties, and surveys for biological control agents have found several important natural enemies and other species that collectively provide appreciable control of this whitefly pest.

Methods to select areas to survey for biological control agents: An example based on growth in relation to temperature and distribution of the weed Conyza bonariensis

A novel approach for selecting areas to survey for biological control agents, incorporating climate and a hypothesised biological control agent, is demonstrated using the target weed Conyza bonariensis (Asteraceae). This weed has become important in Australian cropping regions due to its persistence and herbicide resistance, and it is also increasingly an environmental weed. Both are reasons for the investigation of biological control options. We developed a species niche model for C. bonariensis in CLIMEX based on parameters informed by plant growth and distribution of the species in the Americas. A hypothetical biological control agent (HBCA-cold) was proposed that has its ideal growth range 5°C below that of the weed, so as to favour development of the agent over that of the weed in parts of Australia. The southern part of the weed’s native distribution in Argentina, Chile and the highlands of Ecuador and Columbia were identified as the most suitable areas for surveys that take into account both the climate suitable for the HBCA-cold and the target regions in Australia. This was compared to a model (HBCA-hot) that had an ideal growth range 5°C above that of the weed, but which identified potential areas for surveys in South America that were not climatically aligned with the main regions of the weed’s economic impact in Australia. This species distribution modelling method allows for prioritisation of search areas for biological control agents in the case of widespread target species such as C. bonariensis.

Hydrilla tuber weevil Bagous affinis Hustache (Insecta: Coleoptera: Curculionidae)

Bagous affinis Hustache is a semi-aquatic weevil that feeds on the aquatic invasive plant Hydrilla verticillata (L.f.) Royle. The larvae of the weevil mine hydrilla tubers, and the adults feed on the submerged stems and leaves. The weevil was discovered during surveys for biological control agents for hydrilla in Pakistan in 1980 and was first introduced to the U.S. in Florida from India in 1987. This 5-page fact sheet was written by Emma Weeks, and published by the UF Department of Entomology and Nematology, June 2014.
 EENY595/IN1039: Hydrilla Tuber Weevil Bagous affinis Hustache (Insecta: Coleoptera: Curculionidae) (ufl.edu)

Hydrilla Stem Weevil: Bagous hydrillae O’Brien

Bagous hydrillae O’Brien is a semi-aquatic weevil that feeds on the aquatic invasive weed Hydrilla verticillata (L.f.) Royle. Larvae of the weevil mine hydrilla stems and the adults feed on the stems and submerged leaves. This weevil was discovered during overseas surveys for biological control agents for hydrilla during the 1980s and was first introduced to the U.S. in Florida in 1991 after extensive host-specificity testing. This 5-page fact sheet was written by Emma Weeks, Jim Cuda, and Michael J. Grodowitz, and published by the UF Department of Entomology and Nematology, June 2014.
 EENY594/IN1036: Hydrilla Stem Weevil Bagous hydrillae O'Brien (ufl.edu)

Biology and host range of Omolabus piceus, a weevil rejected for biological control for Schinus terebinthifolius in the USA

Surveys for biological control agents of the invasive weed Schinus terebinthifolius (Anacardi- aceae) discovered two Omolabus weevils (Coleoptera: Attelabidae) feeding on the plant in its native range. Molecular and morphological analysis indicated that one of these species consistently fed on the target weed and the other species fed more broadly. Aspects of the biology and host range of the more specific species, Omolabus piceus (Germar) were examined to deter- mine its suitability as a biological control agent of S. terebinthifolius in the USA. Adults feed on newly formed leaves, and eggs, larvae and pupae develop in curled fragments of leaves, called nidi. Larvae consumed an average of 11.3 (±0.4) mg throughout

Biology and Host Specificity of Ageniosa electoralis (Coleoptera: Chrysomelidae), a Prospective Biological Control Agent for Chrysanthemoides monilifera (Asteraceae)

Abstract The southern African shrub Chrysanthemoides monilifera (L.) T. Non. (Asteraceae) invades native vegetation and threatens nature conservation objectives throughout its range in Australia. In a survey for biological control agents, adults and larvae of the chrysomelid Ageniosa electoralis (Vogel) were found at two sites in Natal, South Africa, where they fed on the foliage of Chrysanthemoides monilifera rotundata (DC.) T. Norl. In laboratory-based starvation tests, A. electoralis completed larval development or oviposited on 15 nontarget test plant species from the Asteraceae and 1 from the Apiaceae. The number of larvae completing development to adults on Arctotheca calendula (L.) M. Levyns, Cymbonotus preissianus Steetz, and Tussilago farfara L. was similar to that on C. monilifera . Also, the number of eggs laid by adults fed Calendula oflicinalis L. or Daucus carota L. was not significantly different from the number of eggs recorded for adults fed on C. monilifera . In multiple-choice tests that included C. monilifera , larvae fed on six nontarget test plant species. Ageniosa electoralis is not being considered for release as a biological control agent for C. monilifera in Australia until a satisfactory level of host-specificity is shown under field conditions in South Africa.

Egg parasitism in Aphelinidae (Hymenoptera: Chalcidoidea) with special reference to Centrodora and Encarsia species

AbstractAphelinidae are all insect parasitoids, and most species are associated with nymphal stages of Homoptera: Sternorrhyncha, either as primary parasitoids or hyperparasitoids. The occurrence of egg parasitism in aphelinids has been recorded in eight of the 38 valid genera and these records are reviewed; it is particularly common in the genus Centrodora, which is shown to be the most polyphagous in the family. One species, C. darwini (Girault), is given special attention because of its occurrence in three recent surveys for biological control agents of crop pests. It is briefly redescribed, diagnosed, and shown to be the most polyphagous aphelinid known. A checklist of Australian Centrodora spp. is given, including the new combination Centrodora grotiusi (Girault) comb. n. The purported evidence for the classification of certain Encarsia spp. associated with eggs of Lepidoptera as ‘heterotrophic parasitoids’ is re-examined and dismissed.

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

Phytophages and Pollinators of Galium (Rubiaceae) in Eurasia and North America

One hundred forty-five species of phytophagous insects, 101 species of pollinators, 7 species of mites, and 2 species of pathogenic fungi were collected on 10 species of Galium in North America and Eurasia during a survey for biological control agents. The European Cecidomyiidae, including Geocrypta galii (H. Low) and Schizomyia galiorum Kieffer, appear to be the most promising natural enemies. Information on the ecology of weedy bedstraws is included.