Abstract booklet - gtö – Society for Tropical Ecology

190 SCIENTIFIC POSTER SESSION | FOYERSCIENTIFIC POSTER SESSION | FOYER191Topic: Link for survival - Science and the conservation of tropical landscapesTopic: Hotspot Wallacea: Understanding the past to save the futureWEDNESDAY | FOYERSPECIATION IN THE NEOTROPICAL GIANT DAMSELFLYMEGALOPREPUS CAERULATUS REFLECTS FOREST FRAGMENTATION(PSEUDOSTIGMATIDAE: ODONATA)Wiebke Feindt 1 , Sandra Damm 1 , Heike Hadrys 11TiHo Hannover, ITZ, Hannover, DE, feindt.wiebke@gmail.comIncreasing fragmentation rates of tropical forests disturb ecological dynamicsand result in loss of biological and genetic diversity. Odonates, which aresensitive indicator organisms, face the destruction of tropical forests asprobably the most important threat (Kalkman et al. 2008). Due to their complexlife cycle and specific habitat preferences odonates come to know an increasingimportance for measuring environmental health and identifying driving factorscontrolling biodiversity. Megaloprepus caerulatus the world´s largest damselflyis widespread in the Neotropics from the South of Mexico to Bolivia (Davies &Tobin 1984, Finke & Hedström 2008). It is highly restricted to primary forests andold grown secondary forests, which provide water filled tree holes needed forreproduction. Females exclusively oviposit in water filled tree holes, which aredefended by males. The size and the density of these microhabitats ultimatelyaffect larval abundance and survivorship (Fincke 2006) resulting in changes inpopulation size and structure. We used two mitochondrial sequence marker(ND1 and 16S rDNA) and microsatellites to analyze the population structure anddiversities between populations covering the northern range of M. caerulatusbetween Mexico and Panama. High sequence divergences and an absenceof gene flow indicate complete separation of all populations studied. Ourresults suggest ongoing speciation processes within the genus Megaloprepusprobably driven by ongoing fragmentation of their forest habitats. Geneticdistances at the species level suggest that the Megaloprepus caerulatus is nota single species rather than a group of at least three species. Our data illustratethe impact of tropical rainforest fragmentation on genetic isolation of a habitatspecialized species and demonstrate how important it is to evaluate geneticdiversities of indicator species. Together with general monitoring data theknowledge about conservation genetic parameters allow to propose refinedconservation decisions in tropical forests.POLLINATION MODES IN THE PIONEER TREE GENUS MACARANGAIN MALAYSIAN RAINFORESTSBrigitte Fiala 1 , Ute Meyer 2 , Ulrich Maschwitz 21Universität Würzburg, Zoologie III, Würzburg, DE, fiala@biozentrum.uniwuerzburg.de,2 Institut für Ökologie, Evolution und Diversität BioCampus –Westend, Frankfurt am Main, DEMany species of Macaranga (Euphorbiaceae) are fast-growing pioneer treeswith an important role in early succession in SE Asian rainforests. The genus isinvolved in diverse types of biotic interactions and it has therefore been a modelsystem for studying mutualistic associations. Despite its ecological importancelittle was yet known about its reproductive biology. A comparative study inthe genus Macaranga in Sundaland revealed specific flower characteristicsand brood-site pollination systems in many species: enclosed inflorescencemorphologies with narrow entrances strongly restrict the set of potentialflower visitors. Different species of thrips were the most abundant insects in 20of the 26 investigated Macaranga species and heteropterans dominated threespecies. They use the flower chambers as breeding sites and feed on nectarproducingtrichomes inside the bracteoles. Both insect groups contributeto pollination, and different plant sections appear to be isolated by differentspecific pollinators. Thrips pollination and myrmecophyty often occurred in thesame clades. The development of enclosed flowers might have facilitated tightant-plant interactions and prevent ant–pollinator conflicts. Due to the ability forexplosive population increase, the pollination by thrips can be of advantage forpioneer trees such as Macaranga. Due to ongoing anthropogenic destructionit has become one of the most abundant tree genera in disturbed Malaysianrainforests. However, the complex ecosystems in which the mutualistic systemsevolved are rapidly changed with unknown consequences for these specificinteractions.Wednesday WEDNESDAY 16:00 | FOYER | FoyergtöSociety for Tropical Ecology | Gesellschaft für Tropenökologie e.V. Status and future of tropical biodiversity | Frankfurt, 21 - 24 February 2011gtö