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( 英 文 ). Nomaki H; Yamaoka A; Shirayama Y;Kitazato H. Journal of Foraminiferal Research,2007, 37(4): 281-286Respiration rates of individual specimens ofdeep-sea benthic foraminifera were measuredunder laboratory conditions. Respiration rates ofnine foraminiferal species—sampled from thedeep-sea floor in Sagami Bay, Japan (750 and1430 m water depth)—were measured at 5°Cwith a microcathode oxygen electrode in a microchamber.Respiration rates ranged from 0.9–9.9 nmol O2 d– 1 ind–1 , with no apparent relationshipwith test size. However, respirationrates varied by species, even from the same microhabitat.The mineralization rate of organiccarbon by the total foraminiferal community wasestimated using the respiration data of this study.The total foraminiferal community is estimatedto respire~46 mg C m–2 to d–1, suggesting thatthe group is an important component of the carbonbudget in the deep sea. Measurement of individualrates of respiration will help determinethe metabolic activity of populations of foraminiferaand their contribution to the carbonbudget in sediments.2008040167捷 克 共 和 国 Umava 山 脉 Vltava 河 上 游 的 有壳 变 形 虫 —— 组 合 中 的 物 种 组 成 和 支 流 环 境的 关 系 = Thecamoebians from the upper Vltavariver (Umava mountains, Czech republic): speciescomposition of assemblages VS. environmentin streams. ( 英 文 ). Katarína H. Journal ofForaminiferal Research, 2007, 37(4): 287-299 2图 版 .Between 1999 and 2002, thecamoebian assemblageswere analyzed in one hundred samplescollected from tributaries of the UpperVltava River (umava Mts., Czech Republic,Middle Europe). The umava Mountains comprisethe largest forest complex in CentralEurope that is still preserved in a near naturalcondition. Diverse fresh-water environments(springs, wetlands, peat bogs, creeks, rivers andponds) characterize the area. Thecamoebian testswere picked from dried 36–500 µm residues. Intotal, eighteen thecamoebian species were identified.The number of species per sample variesfrom one to thirteen, and the assemblages arecharacterized by dominance of Centropyxis orbicularis,C. aculeata, Pontigulasia compressa,Difflugia oblonga and Centropyxis arcula. Anegative correlation (r = – 0.67) is notable betweenabundances of centropyxids and P. compressa.The negative correlation is caused by thedifferent environmental conditions preferred byeach taxon. Assemblages dominated by centropyxidsoriginate mainly from standing water,whereas assemblages with common to abundantoccurrences of P. compressa prefer runningwaterenvironments and substratum withoutcoarse organic debris. Following a flood event inAugust 2002, thecamoebian assemblages weremore diverse and abundant. While reworking ofthecamoebian tests from different biotopes duringflooding probably caused the increase in diversity,a boom in the population of Centropyxisorbicularis after the flood event confirmed theopportunistic character of this species. Boundaryabundances of diagnostic species defined forflowing and standing waters in the forest area (=more than 20% of Pontigulasia compressa forflowing water and more than 50% of centropyxidsfor standing water) can be applied in interpretationof ancient environments. Similarly,changes in thecamoebian assemblages beforeand after the flood event can be used in paleoecology.2008040168美 国 内 布 拉 斯 加 州 林 肯 地 区 附 近 Dakota 组 异常 保 存 的 白 垩 纪 Albian 晚 期 的 有 壳 变 形 虫 =Exceptionally preserved Late Albian (Cretaceous)Arcellaceans (Thecamoebians) from theDakota Formation near Lincoln, Nebraska,USA.( 英 文 ). Hengstum P J; Reinhardt E G; Medioli FS; Gröcke D R. Journal of Foraminiferal Research,2007, 37(4): 300-308 2 图 版 .Thousands of exceptionally well-preservedArcellaceans (Thecamoebians) have been recoveredfrom a Late Albian (Cretaceous) deposit.Sedimentary samples were obtained from aclayey-silt leaf bed in the Dakota Formation,outcropping in a clay pit excavated by the YankeeHill Brick Company, located near Lincoln,Nebraska. Based on recovered freshwatermacrophyte spore and fossil remains, the leafbed is a lagerstätten of paleobotanical remains inwhich the paleoenvironment has been interpretedas a quiescent freshwater setting. The largenumber of recovered thecamoebians revealed ahigh intraspecific variability in test morphologythat is comparable to Holocene thecamoebianpopulations. Consequently, we employ the thecamoebianstrain taxonomic framework, a firstfor ancient thecamoebians. Extant species containedin this collection include Difflugia oblonga,Difflugia protaeiformis, Difflugia urens,Pontigulasia compressa, Lagenodifflugia vas,Cucurbitella tricuspis, Lesquereusia spiralis andthe cysts of environmentally stressed protozoans—withonly one new species reported, Difflugiabaukalabastron. The well-preserved natureof the taxa, suggesting little taphonomicbias, and the lack of significant new species supportsthe current hypothesis of minimal evolutionin thecamoebian lineages through geologictime.52