Volume 1 Number 2 2007

CONTENTS AND ABSTRACTS

Maurizio Sajeva, Francesco Carimi (Italy), Noel McGough (United Kingdom) The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) and its Role in Conservation of Cacti and Other Succulent Plants (pp 80-85)

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Invited Mini-Review: The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) contributes to nature conservation by regulating international trade in listed species by means of a permit system. Through this control system all parties assist in maintaining the listed rare and threatened species in the wild. CITES allows trade in wild specimens up to a level that is not detrimental for the survival of the species in the wild, that is, a use of nature commonly referred to as sustainable use. The basis of CITES are discussed with special emphasis on the Cactaceae and other succulent plants included in the Convention. The framework of regulation of plants in trade is outlined and the impact of illegal trade is discussed. The definition of artificial propagation used by CITES is explained. Additional references and resources for an in-depth study of the convention are provided.

G.U. Sofia Orre, Jean-Marie Tompkins, Mattias Jonsson, Marco A. Jacometti, Stephen D. Wratten (New Zealand) Provision of Floral Resources for Biological Control Restoring an Important Ecosystem Service (pp 86-94)

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Invited Mini-Review: Modern agriculture has greatly altered and fragmented natural habitats globally. This has led to extensive loss of biodiversity and ecosystem services such as biological control. The provision of key components of biodiversity through ecological engineering can partially restore these ecosystem services. Many natural enemies of agricultural pests are omnivores that feed not only on prey but also on plant material such as nectar and pollen. It is possible to improve biological control through the integration of such alternative food sources into agro-ecosystems. We will here review how provision of flowering plants can increase the fitness and abundance of natural enemies, enhancing their suppression of populations of arthropod pests. We will discuss factors that need to be considered to optimise the likelihood of success for this type of ecological engineering. The plant resources provided should increase the fitness and abundance of the targeted natural enemies, but not benefit pests or higher order carnivores. They should be integrated into the agro-ecosystems in a way that is spatially and temporally favourable for natural enemies as well as practical and cost-effective for producers. We will present practical examples of progress and discuss prospects for the adoption of this more sustainable approach to pest management.

Alessandra Nasser Caiafa, Fernando Roberto Martins (Brazil) Taxonomic Identification, Sampling Methods, and Minimum Size of the Tree Sampled: Implications and Perspectives for Studies in the Brazilian Atlantic Rainforest (pp 95-104)

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Original Research Paper: Our aim is to assess the main problems in the studies of tree communities in the Brazilian Atlantic Coastal Rainforest by analyzing methods and sampling criteria used by different authors. We surveyed the literature and built a databank, which included 225 phytosociological tables obtained from 113 publications. Most publications are theses and papers published in non-indexed journals of restricted circulation. The studies concentrate in the southeastern states, and there are large non-surveyed stretches, mainly in the northeastern states. Botanical families with identification problems were always among the ten most abundant ones in every survey. The size of the smallest individual sampled exerted more influence on the results than the sampling method (plots or point-centered quarters), thus making a standardization necessary in future studies. Considering a similar sampling effort, the quarter method sampled a larger number of species than the plot method. The number of individuals sampled was a better indicator of sampling effort than the area sampled. Considering our present knowledge, there is still a great need to survey the Brazilian Atlantic Rainforest and publish the results in adequate journals. However, each survey should obey a minimum set of criteria that yields reliable data. Analyzing the variation of community structure in space and its relation to abiotic variables allows for hypothesis testing and provides key information for planning conservation of natural areas and remediation of degraded vegetation.

Alain Dejean, Bruno Corbara, Jérôme Orivel (France), Maurice Leponce (Belgium) Rainforest Canopy Ants: the Implications of Territoriality and Predatory Behavior (pp 105-120)

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Invited Review: After first being ground-nesters and predators or scavengers, ants became arboreal with the rise of angiosperms and provided plants a biotic defense by foraging for prey on their foliage. Plants induce ants to patrol on their leaves through food rewards (e.g., extra-floral nectar and food bodies), while ants attend hemipterans for their honeydew. Most arboreal-nesting ants build their own nests, but myrmecophytes, plants that offer hollow structures that serve as nesting places to specialized “plant-ants”, illustrate the tight evolutionary bonds between ants and plants. In tree-crop plantations and in some rainforest canopies territorially-dominant arboreal ants have large colonies with large and/or polydomous nests. Their territories are defended both intra- and interspecifically, and are distributed in a mosaic pattern, creating what has become known as “arboreal ant mosaics”. They tolerate non-dominant species with smaller colonies on their territories. Arboreal ant mosaics are dynamic because ant nesting preferences differ depending on the species and the size and age of supporting trees. Because the canopy is discontinuous, arboreal-foraging ants can be found in ant mosaics; invasive ants can affect also the structure of the mosaic. We discuss here the methods that permit us to study these mosaics. Territorially-dominant arboreal ants are good predators that use group ambushing to catch flying insects on their host tree foliage. When producing winged sexuals they also forage for prey on the ground and plunder the colonies of non-dominant species sharing their host tree. When expanding their territories, the workers of the victorious colony raid the defeated colony. Because territorially-dominant arboreal ants prey on herbivores and strongly affect their general activity, ants are frequently used as biological control agents.

Ruth Mony (Cameroun), Brian L. Fisher (USA), Martin Kenne, Maurice Tindo (Cameroun), Alain Dejean (France) Behavioural Ecology of Bark-digging Ants of the Genus Melissotarsus (pp 121-128)

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Original Research Paper: In Melissotarsus beccarii and M. weissi, two ant species which damage trees by digging nest galleries in bark, we observed numerous egg-producing physogastric queens situated more than one meter from each other, but within the same colony, making this the first record of oligogyny in this genus. Our analysis of ovarian development and degree of mandible wear reveals that a temporal polyethism exists and that gynes perform the worker duty of digging galleries. This is a new and previously unreported case of worker-like behaviour in gynes. These ants appear to follow a dynamic process wherein newly-inseminated gynes accepted by colonies perform worker-like tasks and do not produce eggs until they have the opportunity to dominate their own section of the colony and become physogastric. Workers that elude the queen’s influence and produce chorioned, viable eggs probably play a role in the control of reproduction by non-physogastric gynes. Intraspecific aggressiveness between colonies was low. While spreading beneath the bark, both incipient and mature colonies can merge, forming very large colonies over vast areas of bark. This study demonstrates that Melissotarus should be of special concern for the management of forest and tree crop plantations.

Wesley A.C. Godoy (Brazil) Dynamics of Blowfly Populations (pp 129-139)

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Invited Mini-Review: Blowflies have been recognised as useful biological experimental models for studies of population dynamics. These flies have received special attention because some species typically show an oscillatory behaviour, as reported for Lucilia cuprina by A. J. Nicholson. About 30 years ago, four Old World species of blowflies of the genus Chrysomya were introduced to the Americas, where they apparently displaced native species. Laboratory experiments were combined with mathematical models in an attempt to better understand the population dynamics of blowflies in the context of this biological invasion. The application of mathematical modelling has revealed different patterns of oscillation for the native and the exotic species. Experiments focussed on interspecific interactions have also provided important results in the context of the dynamics of interactions between native and exotic species. This mini-review is an attempt to synthesise results centred on the dynamics of blowflies during recent years, focussing primarily on the connection between experiments and mathematical modelling and considering the biological invasion scenario.

Nelice M. Batistelli, Karina S. Paduan, Paulo E.M. Ribolla, Wesley A.C. Godoy (Brazil) Population Variability of Exotic and Native Blowflies in Brazil, Based on Mitochondrial DNA Sequences (pp 140-144)

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Original Research Paper: A molecular phylogeny analysis was performed on blowfly species. Molecular analyses entailed the comparative sequence analysis of the cytochrome oxidase subunit I (COI) DNA, amplified from individuals by means of the polymerase chain reaction (PCR). The 310 base pairs of the mitochondrial COI sequences analysis were analysed, and revealed the existence of 235 invariant sites and 75 polymorphic sites, with 71 parsimony informative sites. Invariant positions in the sequence were removed, and the remaining variant positions in the sequence indicated the number of substitutions supporting the divergence of the taxa. The gene analyses revealed the existence of different haplotypes in Chrysomya albiceps, Cochliomyia macellaria, and Lucilia eximia. Phylogenetic analyses through tree topology showed the existence of well-defined mitochondrial lineages among exotic and native blowflies. Seven distinct congeneric clusters were formed based on the sequence data. The results are discussed in genetic and ecological contexts.

Nelice M.B. Serbino, Wesley A.C. Godoy (Brazil) Seasonal Abundance and Distribution of Necrophagous Diptera in Western São Paulo State, Brazil (pp 145-149)

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