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Allogromiids are classically defined as agroup of monothalamous, soft-walled foraminiferans.Recent morphological, cytological, andmolecular studies, however, challenge this view,showing that the soft-walled allogromiids areclosely related to naked athalamids and unilocularagglutinated foraminiferans. To establish thephylogenetic relationships among these threegroups we obtained partial small-subunit ribosomalDNA sequences of 50 species and undeterminedmorphotypes, and compared them toother foraminiferal taxa. Phylogenetic analysesof our data show that allogromiids, athalamidsand astrorhizids comprise an assemblage of 13lineages branching together at the base of theforaminiferal tree. Among these lineages, twoare represented by a single species and fourcomprise similar genera, while the remainingseven are heterogeneous groups composed ofseveral species having different types of wallstructure and different test morphologies. Alllineages are relatively well supported, yet therelationships among them are not resolved. Inview of our data, we propose to revise the definitionof allogromiids to include all naked and testateunilocular granuloreticuloseans that divergedearly in the evolution of Foraminifera.2008040216日 内 瓦 湖 淡 水 有 孔 虫 类 的 过 去 和 现 在 =Freshwater foraminiferans from Lake Geneva:past and present. ( 英 文 ). Holzmann M; PawlowskiJ. Journal of Foraminiferal Research,2002, 32(4): 344-350 1 图 版 .Allogromiid foraminiferans are distributedover a wide range of marine habitats, but someare also reported from freshwater environments.Most of these descriptions date back to the 19thcentury. Among them, five species of freshwaterforaminiferans have been described and redescribedfrom Lake Geneva by the Swiss protozoologistEugène Penard. The different foraminiferalspecies were classified by Penard inthe genus Gromia, which at that time includedboth, filosean and granuloreticulosan species andwere later grouped by De Saedeleer in two allogromiidgenera, Allelogromia and Diplogromia.We collected several sediment samplesfrom Lake Geneva and from two other bodiesof freshwater in Switzerland and investigatedthem subsequently under a stereomicroscope.None of the forms described by Penard wereobserved. On the other hand, we have obtainedforaminiferal DNA sequences from DNA extractsof the same sediment samples. Phylogeneticanalysis of these sequences shows that theybranch with a clade of saccamminid foraminiferans,represented by the genera Ovammina andCribrothalammina. This is in agreement with theobserved morphological similarity betweenPenard’s species and the marine saccamminidsused in our study. The possibility that our sequencesbelong to some undetermined nakedforaminiferans, however, cannot be excludedand the molecular identification of the speciesdescribed by Penard must await the confirmationby sequencing DNA of isolated specimens.2008040217瑞 典 西 海 岸 一 个 大 的 单 房 室 有 孔 虫 新 属 新 种Toxisarcon synsuicidica = Toxisarcon synsuicidican. gen., n. sp., a large monothalamousforaminiferan from the west coast of Sweden.( 英 文 ). Cedhagen T; Pawlowski J. Journal ofForaminiferal Research, 2002, 32(4): 351-357 3图 版 .A new foraminiferan, Toxisarcon synsuicidican. gen., n. sp., is reported from clay bottoms ofKosterfjorden (Sweden). The species is characterizedby a large irregular cell body covered byan organic lining to which foreign particles areattached. It resembles an irregular clump of detritusor sediment aggregation and it can thereforeeasily be overlooked. Marine biologists whohave worked intensively with benthic fauna inthe area have never observed it despite the factthat it is quite common. The peculiar feature ofthe new species is its capacity to stock toxicproducts that can be harmful to itself if accidentallyreleased.2008040218英 国 苏 格 兰 西 海 岸 Linnhe 海 湾 新 种Toxisarcon alba 的 系 统 学 和 生 态 学 = Taxonomyand ecology of Toxisarcon alba, sp. nov.from loch Linnhe, west coast of Scotland, UK.( 英 文 ). Wilding T A. Journal of ForaminiferalResearch, 2002, 32(4): 358-363 2 图 版 .Toxisarcon alba n. sp., is a giant, naked marineforaminiferan recorded at two locations onthe west coast of Scotland, UK. Individuals werefound buried or semi-buried in well-oxygenatedsilty sand at 10 to 30m water depth. A distinctive,slightly raised mound of 18–40mm diameter,through which there were many perforations,indicated the presence of an individual on theseabed. Partial removal of the overlying sedimentrevealed the naked opaque, white, stickycell body. Toxisarcon alba exists in three distinctforms. In the most commonly occurringform (and the only form observed in the field),the central portion of the cytoplasm extends peripherallyinto numerous large cytoplasmic extensionsand reticulopodia (branched form). Inaquaria, some individuals transformed into aconsolidated form (spheroid form) by retractingmost or all of the reticulopods resulting in a cellwith a very well defined edge. On four occasionsa third very diffuse form, resembling a fungal69