Oral Abstracts Phylogeny of Syllidae (Phyllodocida, Annelida) based on morphogical data M. Teresa Aguado* & Guillermo San Martin Laboratorio de Biologia Marina, Faculte de Ciencias, Universidad Autonoma de Madrid, Canto Blanco, Spain The phylogeny of Syllidae is assessed in a parsimony analysis of morphological characters. All the valid genera of the four classical subfamilies Eusyllinae, Exogoninae, Syllinae and Autolytinae, as well as several outgroup taxa from other families of Phyllodocida are included. Character informa- tion is based on examination of available types, additional non-types and newly collected material. The monophyly of the four subfamilies as well as the whole Syllidae is discussed. The evolution of the reproductive modes and the different systems of parental care are also considered. Results are compared with those from previous studies and with the most recently published phylogenetic analy- sis of Syllidae based on molecular data from nuclear 18S rDNA and mitochondrial 16S rDNA and cytochrome c oxydase subunit I. Our study also aims to investigate the evolution of some morpho- logical characters traditionally used for the diagnosis of the classical subfamilies and their genera. Presenter (*) 22 Oral Abstracts Polychaete diversity on the Northeast Greenland Shelf: effects of water column processes and grain size William G. Ambrose, Jr.*, Paul E. Renaud & Kirsti A. Sandoy Department of Biology, Bates College, Lewiston, Maine 04240 Arctic shelves are areas of complex bathymetry and hydrography, offering opportunities to examine patterns of benthic community structure along environmental gradients and potentially determine biotic and abiotic controls on diversity. The Northeast Water Polynya is a recurrent annual feature of variable size on the northeast Greenland shelf. The area is characterized by complex bathymetry: shallow banks (water depth <40–150 m), surrounded by troughs (water depths of 250 to > 500 m). The distribution and abundance of polychaetes and other benthic taxa are primarily related to parameters characterizing organic input to the benthos (water column and benthic pigments). Over 150 polychaete species were identified from replicate cores (0.005 m?) from 28 stations with no indication that the sampling effort was sufficient to collect all the species present. The southern trough had significantly fewer polychaete species per sample (14.7) compared to stations from the northern trough (23.4) or central bank (25.7). The Shannon diversity index and rarefaction curves confirmed the lower diversity in the southern trough compared to the bank and northern trough. The southern trough has greater ice cover than the central bank and northern trough which open earlier in the season, so it is tempting to explain the lower polychaete diversity in the south compared to the north by differences in water column productivity between these areas. Both polychaete species richness and the Shannon diversity index are negatively correlated with grain size, however, and stations in the southern trough have a finer sediment and greater depth than other areas sampled. Presenter (*) 23 Oral Abstracts The biological geography of the European Seas: results from the macrofaunal inventory of the soft-substrate communities Christos Arvanitidis1*, P. Somerfield, H. Rumohr, S. Faulwetter, V. Valavanis, K.Vasileiadou, G. Chatzigeorgiou, E. Vanden Berghe, J. Vanaverbeke, C. Labrune, A. Gremare, M. Zettler, M. Kedra, M. Çodarska-Kowalczuk, D. Fleischer, M. Büntzow & A. Rose 1 HCMR—IMBG, P.O. Box 2214, Heraklion, Crete 71003, Greece This work has been accomplished in the context of the MarBEF (Marine Biodiversity and Ecosystem Functioning) EU Network of Excellence. The hypothesis tested is whether the zoogeo- graphical regions defined across European seas exist or not. The systems considered were those proposed by OSPAR, ICES, IHO, LMEs, Longhurst and Fredj. Data on soft-bottom communities have been stored in the largest data base of this kind ever developed in the EU. The faunal groups used for the hypothesis testing were: macrobenthos, polychaetes, molluscs, crustaceans, echino- derms and sipunculans. Three criteria were proposed in order to test the perfomance of the above taxa through the application of a variety of uni- and multivariate methods: (1) interpretability, which refers to the biogeographic patterns produced by each group for each system; (2) differenciation, which provides a measure of the uniqueness of the pattern; (3) randomness, which defines the inventories of the various sectors as random samples of the total inventory of each of the systems considered. Results show that only polychaetes meet all three criteria and, accordingly, the only valid marine biogeographic system is the one proposed by Longhurst. The application of recently developed third-stage MDS shows that polychaetes produce a unique pattern when all systems are considered and also that they produce the pattern with highest similarity to the one produced by the macrobenthos, within Longhurst’s system. Average island distance from the nearest coast, number of islands and the island surface area were the geographic variables best correlated with the pattern produced by polychaetes. Presenter (*) 24 Oral Abstracts Comments on the validity of three common Harmothoe species (Polychaeta: Polynoidae) in the NE Atlantic Ruth Barnich* & Dieter Fiege Sektion Marine Evertebraten II, Forschungsinstitut und Naturmuseum Senckenberg, Senckenberganlage 25, D-60325 Frankfurt, Germany The scaleworms Harmothoe imbricata (Linnaeus, 1767), H. extenuata (Grube, 1840), and H. impar (Johnston, 1839) are the most abundant and regularly identified Harmothoe species from shallow waters in the NE Atlantic. Unfortunately their type specimens are lost and the original descriptions and figures are insufficient for differentiation from other Harmothoe species occurring in the same habitat. Thus, these species are indeterminable and their names should not be used in the future. Identification keys covering these species are based on redescriptions by different authors published after the respective original description. They represent the opinion of these authors about the dif- ferentiating characters, but it is not possible to prove whether this really meets the intention of the original authors. Our review of the literature revealed that Harmothoe cirrata (Müller, 1776) (origi- nally described as Aphrodita cirrata) is the oldest sufficiently described species covering specimens hitherto identified as H. “imbricata”. As to H. “extenuata” specimens, they are perfectly covered by H. propinqua (Malmgren, 1867) (originally as Lagisca). In the case of H. “impar” specimens, H. reticulata (Claparède, 1870) (originally as Polynoe) is the oldest sufficiently described and fig- ured species. In the NE Atlantic alone about 30 valid Harmothoe species occur, with about 50% of them having been described already in the 19th century. Thus, our results will not only influence forthcoming taxonomic and ecological research on the group in the region, but will be most impor- tant for the revision of the whole genus. Presenter (*) 25 Oral Abstracts Cosmopolitan deep-sea polychaete species James A. Blake1* & Markus Böggemann2 1 ENSR Marine & Coastal Center, Woods Hole, MA 02543 USA 2 University of Osnabrück, Osnabrück 49069, Germany As part of recent collections of benthic invertebrates from continental slope and abyssal depths from the North and South Atlantic, eastern Pacific, Antarctica, and the central Pacific gyre, some poly- chaete species with apparent “cosmopolitan” distributions were identified. The dorvilleid, Exallous cropion Jumars, from the San Diego Trough off California has been identified from off North Carolina. Ten additional dorvilleid species in five genera have been confirmed as occurring in deep- water surveys off both the U.S. Atlantic and Pacific coasts. Glycera capitata Örsted (Glyceridae), Bathyglycinde profunda (Hartman & Fauchald), B. sibogana (Augener & Pettibone), and Progoniada regularis Hartman (Goniadidae) have been reported in recent deep-sea surveys in the Atlantic and Pacific. Several widely distributed species of Ophelina (Opheliidae) are known as are several species of Aricidea, Cirrophorus, and Levinsenia (Paraonidae). For example, A. simplex (Day), from off South Africa, has been commonly encountered off both the east and west coasts of North America. Mystides caeca Langerhans and M. rarica (Uschakov) (Phyllodocidae) are widely distributed in the Atlantic and Pacific. Among spionids, Aurospio dibranchiata Maciolek, from North and South Atlantic basins, also occurs off California. Prionospio delta Hartman, from off NE South America is a dominant species on the lower continental slope off California. The small syllid Anguillosyllis (=Braniella) palpata (Hartman), from Antarctica has been found in slope sediments off the east and west coasts of North America. Another small syllid Parexogone wolfi San Martín is widely distributed in Atlantic abyssal basins. The question of how small infaunal polychaetes can occur over vast geographic areas is a fascinating question. Large areas of the deep sea floor have few geographic barriers to block species migrations. In addition, very cold Antarctic bottom water (0.5–1.5°C) flows northward from the Weddell Sea at abyssal depths into Atlantic and Pacific basins and influences water depths greater than 3000 m in both oceans. The abyssal habitat there- fore has a constant environment and with few barriers to migration