12th International Conference on Harmful Algae

INTERNATIONAL SOCIETY FOR THE STUDY OF HARMFUL ALGAE12 th <strong>International</strong> <strong>Conference</strong> on Harmful Algae, Copenhagen, Denmark, 4-8 September 2006Due to sudden mortality after theaccumulation period we could notevaluate toxin elimination in thescallops. The oysters, havingaccumulated less DST than themussels, also showed faster toxinelimination rates. DSTconcentration in the oysters did notexceed half the regulatory limit,despite high water column toxicitythat resulted in concentrationsalmost 10 times the regulatory limitin the mussels.PO.05-18Deoxy cylindrospermopsin,detection in the benthicfreshwater cyanobacteriumLyngbya wollei from AustralianstreamsSession: PO.05 - Toxin analysisG K Eaglesham 1 , M Seifert 2 , GRShaw 3 , W Wickramasinghe 41 Queensland Health Scientific Services,BRISBANE, Australia2 University of Queensland, BRISBANE,Australia3 Griffith University, LOGAN CITY, Australia4 Entox, BRISBANE, AustraliaCylindrospermopsin and its deoxyanalogue have been detected in anumber of cyanobacteria throughoutthe world. Previously in Australiathese toxins have been reported inCylindrospermopsis raciborskii andAphanizomenon ovalisporum. Inboth these species the deoxycylindrospermopsinlevels are lessthan 10 % of the predominant toxin,cylindrospermopsin. Lyngbya wolleispecimens from several streams inSouth East Queensland were foundto contain deoxycylindrospermopsinas thepredominant toxin with only lowlevels of cylindrospermopsin. Thelevel of toxin in the water was belowthe detection level of 0.2micrograms per Litre in contrast tothe other two species mentionedwhich often give toxin levels in thesurrounding water at similarconcentrations to the toxin contentof the cells. This is the first report ofthese toxins being detected in abenthic cyanobacterial species.PO.12-07Haplo-diploid life cycles in thegenus Chrysochromulina(Haptophyta)Session: PO.12 - Taxonomy andPhylogenyB EdvardsenUniversity of Oslo, OSLO, NorwayA heteromorphic haplo-diploid lifecycle appears to be commonamong haptophytes and has beenfound in Chrysochromulinapolylepis. To assess whether otherChrysochromulina species mayhave a haplo-diploid life cycle,coding and non-coding ribosomalDNA regions, body scalemorphology, cell size and ploidylevel were examined in 30 strainsrepresenting 16 Chrysochromulinaspecies. All described species haddistinct SSU rDNA sequences,except strains of C. hirta and C.ericina, which were identical in thisregion, suggesting that they havediverged too recently to haveevolved differences in this gene, oralternatively are conspecific. Twoploidy levels differing by a factor oftwo assumed to represent haploidand diploid stages, each capable ofvegetative cell divisions were foundin five species: C. ericina, C. hirta,C. kappa, C. rotalis and C.polylepis. Haploid and diploid cellsof C. kappa and C. ericina hadsimilar scale morphology, but wereheteromorphic in C. hirta, C. rotalisand C. polylepis. All strains within aspecies had identical ITS1 rDNAsequences. These results suggest166