Exploratory field surveys of the natural enemies associated with balloon vine Cardiospermum grandiflorum Swartz, an environmental weed in South Africa, Australia and other countries, were conducted in northern Argentina from 2005 to 2009. The surveys included other plant species in the genus Cardiospermum and other native Sapindaceae, permitting an assessment of the distribution and host range of the natural enemies.Seventeen phytophagous insects in five orders and ten families, and two fungal pathogens were found. The nature of the potential agents' damage, their field distribution and abundance, and the results of preliminary host-specificity testing indicated that the seedfeeding weevil Cissoanthonomus tuberculipennis (Coleoptera: Curculionidae) and the fruitgalling midge Contarinia sp. (Diptera: Cecidomyiidae) were the most promising biological control agents for C. grandiflorum outside of its native range.

ABSTRACT. Recent surveys in southern Florida, USA, Brazil and Argentina, for biological control agents to assist in the control of the invasive Brazilian peppertree, have discovered several previously unknown species of plant mining Lepidoptera of the family Gracillariidae. Morphological descriptions with summaries of their biology for the following four new species and one new genus are presented: Caloptilia schinusifolia Davis and Wheeler, from Brazil and possibly Argentina; Eucosmophora schinusivora Davis and Wheeler, from Argentina and Brazil; Leurocephala schinusae Davis and Mc Kay, new genus and species, from Argentina and Brazil; and Marmara habecki Davis, new species, from Florida, USA. The larvae of all four species exhibit a hypermetamorphic development consisting of early instar sapfeeding and later instar tissue feeding stages typical for members of Gracillariidae. Larvae of M. habecki were also observed to possess an additional nonfeeding, transitional instar prior to the final instar as is typical for the genus (Wagner et al. 2000). Larvae of the new genus Leurocephala were discovered to undergo an intermediate, nearly apodal tissue feeding stage between the sapfeeding and final tissue feeding instars. Unique specimens representing an additional three species of Gracillariidae also have been reared from this tree in Argentina or Brazil, but these could not be identified because of inadequate material. COI barcodes were obtained for Marmara habecki, M. smilacisella, and an undescribed Marmara from Brazil. Each species was separated by a minimum barcode divergence of > 4.5% (Fig. 111).

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1. Consumer-resource species interactions form complex, dynamic networks, which may exhibit structural heterogeneity at various scales. This study set out to address whether host-parasitoid food web size and topology vary across forest canopy strata, and to what extent foliar resources and species abundances account for vertical patterns in network structure.2. The vertical stratification of leaf miner-parasitoid food webs was examined in two monotypic beech (Nothofagus pumilio) forests in northern Patagonia, Argentina. Quantitative food webs were constructed for separate canopy layers by sampling foliage from three tree-height classes at 0.5-1, 2-3 and 5-6 m above ground.3. Leaf miner abundance per unit leaf mass and foliar damage (%) did not differ across strata, although foliage quality and quantity increased from the understorey to the upper canopy. Parasitism rates and food web complexity decreased with canopy height, as reflected by reduced linkage richness, linkage density, mean interaction strength, and host vulnerability. 4. Null model analyses revealed that food web metrics, especially in the upper canopy, were often lower than expected when compared with randomly structured networks. Overall, these patterns held for two forests differing in vertical structure and in dominant miner morphotype and parasitoid species.5. These results suggest that vertical declines in network complexity may be driven by the parasitoids' limited functional response to host abundance and dispersal from pupation sites in the forest floor. A broader constraint on food web structure seemed to be imposed by host-parasitoid trait matching, a reflection of large-scale assembly processes.