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mycelium, was observed where reticulopodiawere spread over the sediment surface. The closestrelated species, based on analysis of ribosomalDNA sequences, is the newly describedToxisarcon synsuicidica.2008040219南 极 洲 Explorer Cove 的 一 个 似 Allogromiid的 胶 结 有 孔 虫 Astrammina triangularis (Earland)的 结 构 、 系 统 分 类 位 置 和 生 态 = Structure,taxonomy and ecology of Astrammina triangularis(Earland), an allogromiid-like agglutinatedforaminifer from Explorers Cove, Antarctica.( 英 文 ). Bowser S S; Bernhard J M. Journalof Foraminiferal Research, 2002, 32(4): 364-374 6 图 版 .Astrorhiza triangularis (Earland) is transferredto the genus Astrammina based on structuraland molecular analyses of abundant materialcollected from Explorers Cove, McMurdoSound, Antarctica. This large, unilocular agglutinatedspecies was previously known from only14 specimens collected on the Atlantic side ofthe Antarctic continent. It resembles Astramminarara in possessing an allogromiid-like sarcode(cell body) and laminated theca surrounded by alarge intratest space. Astrammina triangularismakes an important contribution to foraminiferalbiomass in Explorers Cove. Live specimens areorientated upright in the sediment and, in laboratoryexperiments, feed on algal and metazoanprey.20080402203 个 现 代 Allogromiid 有 孔 虫 的 个 体 和 细 胞 体超 微 结 构 比 较 — 高 压 凝 结 和 冻 结 置 换 的 应 用= Comparison of test and cell body ultrastructurein three modern allogromiid foraminifera: applicationof high pressure freezing and freeze substitution.( 英 文 ). Goldstein S T; Richardson E A.Journal of Foraminiferal Research, 2002, 32(4):375-383 4 图 版 .Three modern representatives from the OrderAllogromiida sensu lato (Myxotheca sp., Cribrothalamminaalba, and Hyperammina sp.)were prepared for ultra-structural observationsusing high pressure freezing followed by freezesubstitution, methods that greatly improve thequality of fixation of both the cell body ofsmaller Foraminifera and the test. The three taxaexamined illustrate three different types of testconstruction. Myxotheca sp. has an organic testcharacterized by a distinct herringbone pattern, afeature found in several other monothalamousForaminifera. Cribrothalammina alba, alongwith several other saccammininds, has a flexibletest that is in contact with the cell body andconsists of a finely fibrous IOL (inner organiclining) and prominent agglutinated layer.Though Hyperammina sp. also has an IOL andprominent agglutinated layer, the IOL consists ofa thin band of crescent-shaped fibers and thusdiffers from that found in C. alba and similarsaccamminids. Such ultrastructural differencesmay reflect differences in the mode of growth ofthese two taxa: C. alba grows by expanding itssingle-chambered test whereas Hyperamminagrows by lengthening a conical test. Foraminiferalsystematics has been based almost exclusivelyon test composition and structure. Identifyingthe general themes of test fine structureand construction in the otherwise morphologicallysimple allogromiids should contribute to abetter understanding of systematic relationshipswithin the group.2008040221有 机 质 壁 有 孔 虫 Allogromiids 在 海 洋 环 境 中的 产 出 、 分 异 度 和 生 态 = Organic-walled Allogromiids:aspects of their occurrence, diversityand ecology in marine habitats. ( 英 文 ). GoodayA J. Journal of Foraminiferal Research, 2002,32(4): 384-399 2 图 版 .Foraminifera with an organic, or predominantlyorganic, test wall (‘allogromiids’ in thetraditional sense) are an important, diverse butoften overlooked component of marine benthiccommunities. This paper reviews some of thescattered literature on these protists. They varyfrom 90%. In contrast, organic-walledallogromiids and other monothalamous formsare usually relatively uncommon in dysoxic settings.Experimental and field studies support the70