Three new dinoflagellate species, Karenia papilionacea sp. nov., Karenia selliformis sp. nov., and Karenia bidigitata sp. nov., were compared with the toxic species Karenia mikimotoi (Miyake & Kominami ex Oda) G. Hansen & Moestrup, Karenia brevis (Davis) G. Hansen & Moestrup, and Karenia brevisulcata (Chang) G. Hansen & Moestrup using the same fixative. Distinguishing morphological characters for the genus Karenia included a smooth theca and a linear apical groove. The new species can be distinguished on the basis of morphological characters of vegetative cells that include the location and shape of the nucleus; the relative excavation of the hypotheca; the characteristics of apical and sulcal groove extensions on the epitheca; the cellular shape, size, and symmetry; the degree of dorsoventral compression; and the presence of an apical protrusion or carina. Species with pronounced dorsoventral compression swim in a distinctive fluttering motion. An intercingular tubular structure traversing the proximal and distal ends of the cingulum is common to the species of Karenia, Karlodinium micrum (Leadbeater & Dodge) J. Larsen, Gymnodinium pulchellum J. Larsen, and Gyrodinium corsicum Paulmier. Molecular phylogenetic analyses of rDNA sequence alignments show that the new species are phylogenetically distinct but closely related to K. mikimotoi and K. brevis.

Seven new compounds (1-6 and 10) with a unique carbon skeleton have been isolated from the sponge Hamigera tarangaensis, and the structure of a previously reported metabolite has been revised from 12 to 8. The structures have been assigned from extensive NMR examination. Compounds 3-6 showed moderate in-vitro cytotoxicity against P-388, while 3 showed 100% in-vitro virus inhibition against both the Herpes and Polio viruses, with only slight cytotoxicity.

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Cladograms for the same group of taxa deri ved using different datasets often agree extensively but are seldom identical. This disagreement may be due to the fact that cladograms are sampling estimates of the true phylogeny and as a result may differ only because of sampling erro~. A protocol is proposed to test the null hypothesis that two trees estimate the true or parametric phylogeny and are no more different than would be expected due to sampling error. In the event that the null hypothesis is rejected, the datasets are pruned to remove potentially confounding information, and the test of the null hypothesis is repeated. If the null hypothesis cannot be rejected, a method for combining the cladistic information from both datasets is proposed that takes account of the variability of the cladistic structure. The procedure is illustrated using morphological and molecular data from genera of the sponge Order Hadromerida (Porifera: Demospongiae).